Head Pie has received permission from FiiO to reprint their `FiiO`s Foundations` a series of articles charting the history, growth and change of FiiO.
This has appeared on their forums and Facebook page.
I read it and thought it deserved a larger audience and also in keeping with the Head Pie ethos thats its not just about the products, but the history and the people who design and make them.
FiiO's first product back in 2007: Dock / loudspeaker PS1120 for Meizu players.
Unibody screwless design, powered by 4 AA batteries or USB power; dual 50mm high quality full-range drivers; high-efficiency Class D amplifier rated for 3Wx2; dock for Meizu mp3 players for sound amplification, data connection and charging.
The year was 2006. I was retired, with a placeholder job as a consultant at a friend's loudspeaker business. I opined, “Meizu mp3 players are selling pretty well, we can probably make good money making a dock for them”. We contacted Meizu, and indeed they had the same plans, even including an exterior design already given by a Korean design house.
Everything came together immediately, with my friend's factory responsible for sound tuning, circuit design and production, to be branded Meizu and sold by Meizu. Things went south (as they inevitably do in real life) when, after several months’ of design and having bought all the components for the production run, Meizu told us they're not interested in buying anymore.
As I was very confident of the quality of the product-to-be, and we had already gone so far along in preparing to produce it—we'd already spent RMB40,000 in moulds for the various parts alone—I got a few of my friends to join me and establish a company for producing and marketing this dock—this is how FiiO was founded. This was the start of FiiO's team, brand and sales avenues.
All in all (including its derivatives), we sold several tens of thousands of these docks, recovering our R&D costs. Finally, we’d like to point out that we started off making loudspeaker docks, not PSU bricks for Meizu as some mistakenly think.
FiiO's second product: Portable loudspeaker PS1110.
World's thinnest speakers utilizing 2 AAA batteries; two 27mm high performance drivers utilizing neodymium magnets; no thicker than an iPhone 1. The front bezel was the world's first mirror finish loudspeaker grille made using stainless steel etching.
This micro loudspeaker was built to complement mp3 players, boasting tiny form factor and ultimate portability in a finely built body. The only regret was that the small size led to relatively poor sound quality. We sold about 10,000 of these, selling some overseas—but this was a commercial flop, relatively speaking. Even so, a few factories in Shenzhen went ahead and cloned our design grin.
FiiO's 3rd product: the E3 portable headphone amplifier.
FiiO had clear, well defined business plans when we started off. But some of those initial plans got shoved aside when this micro headamp, a “niche” product that most of us dismissed and sent to production “just in case”, came out of left field and bowled us over with its sales and opened the door to success.
The E3 was driven by a single AAA battery to output 70mW per channel, far more than your average mp3 player; a bass boost circuit was included. The headphone jack doubled as the on/off switch (i.e. It turns on automatically on headphone insertion); other than that it had no switches. The eyelet let you hook a strap to it, which helped you not lose this tiny device.
A member of the largest headphone users’ online community in the world stumbled upon our product, bought it from eBay (from a HK seller) and found it to be good. Others gave it a try and most exclaimed upon its tininess, cheapness and goodness compared to other products at the price and other products from China.
Thanks to “sugarinthegourd”, this FiiO microamp went from selling nowhere for $1.30 ex shipping (ouch?), through direct sales to users and increasing reputation via word of mouth, to becoming a long running mainstay at FiiO that stayed in production until 2014 (not for lack of further orders!). Also thanks to this episode, we discovered all new methods of development and marketing, leading to our current leading position in sales volume of headphone amplifiers and sowing the seeds of our DAP business of today. The E3 sold over ten thousand units and was the pivot that turned FiiO from loss to profit.
FiiO’s fourth product was the multifunctional power unit P3. As a mobile USB power supply, AC-USB adapter and NiMH battery charger all rolled into one, it was the recipient of granted patents and the ideal partner on business and holiday trips alike.
Connected to AC power, the P3 outputs standard 5V/2A USB power.
It also contains 2 battery slots for charging AA/AAA NiMH batteries.
Its party trick came into play when the P3 was out and about with batteries still in those two battery slots: it inverts its circuits and draws and upconverts power from the batteries, once again providing 5V USB power. In effect, it’s the portable USB power bank we’re all familiar with today, powered by removable batteries.
This product would still be a nice one today—7 years later—but squeaked to a halt after selling less than 10,000 units back in 2008—2008, when dumbphones still walked the planet and the battery life of phones, music players and cameras alike were measured in days, not hours. The P3 was simply not a product of its time.
And now for something whose time had come… the S3.
Powered by two AA batteries, the S3 was yet another loudspeaker-type product (seeing as the team was assembled partly from a loudspeaker factory…) with stereo 1.5” full-range drivers, driven to 1Wpc. Its claim to fame was the ability to directly play SD cards loaded with music, together with basic song navigation and volume control. Of course, amplification of line-in signals via the 3.5mm port was also supported.
It also came with its own special strap that could double as a stand for the speakers.
The S3 was pretty well received by the market. Then it was a little TOO well received by the market, wherein loads and loads of me-too factories joined the fray and copied the modus operandi of the me-too factories that flooded the market with boatloads of mp3 / mp4 players a few years ago, wherein PCB design companies produced the circuit designs and sold PCBs, moulding companies designed the exterior design and sold shells, and the me-too companies simply put things together, did rudimentary QC and then pushed the mp3 speakers everywhere.
With this mode of operation, these companies together enjoyed massive economies of scale, such that they could churn out new models for the same retail price as what it cost us in parts alone. Therefore we eventually had no choice but to leave the speaker business.
FiiO’s sixth product on its enterprising startup journey was the E5. Which was a true classic, as it featured prominently in our product line and our sales for 3 years, to be succeeded by the E06, which will in turn meet its successor this year. Being the start of a successful product line for eight years running, it had great portability, sound quality and looks, which continued and will continue to be refined by its successors.
The E5 was a product of users’ requests regarding our first successful product the E3: an independent power switch was added, and it sported its own volume control. The bass boost became an option rather than always-on. To keep the size small with all these additions, the E5 became the first FiiO to utilize an internal Li-polymer battery. This freed even more room and power for building a higher-end, more powerful amplification stage, paving the way for a big leap in sound quality.
Price was higher than the E3 but still decidedly budget friendly. Coupled with the high quality metal build and tiny size, it started making big waves worldwide soon after release, and was sold out at the factory for months on end, despite continuous production.
The E5 succeeded not merely in selling itself, but also in making FiiO known to users worldwide, so that distributors phoned in from around the world asking to be our agent. Thus it earned our foothold in the international audio dealer network and helped us become a household name in HiFi circles. Speaking of which, our prices are indeed suitable for utterance in the *household* and may have saved many an avid headphone HiFier from being sent to the doghouse by their spouse.
The LCD TV had replaced CRTs for not long in China as of 2008. Soundbars were a relatively new and popular alternative speaker setup overseas. Somebody came up with the brilliant idea of making a soundbar for computer LCDs! Nobody has made one—we’ll be the first! First guy in always wins, right? Right?
So we spent months designing and tooling for this new product.
3. Wonder of wonders, whereas HT speakers are too big to fit many homes, users actually have plenty of room on their desk for computer speakers…?
Everybody thought this was a good idea. N3 mini USB speakers, with volume control… pretty good sound… (they better sound good, we spent over 100,000RMB tooling for them) They look ok too I guess (you be the judge).
It didn’t take a genius to find out that one particular model of these from a particular brand were starting to sell like cupcakes at computer malls (but we did send out a scout party to make sure of just that). So we made one too. Which took a few months. Then when it was ready to sell, we found that everybody and his mom have come up with one too. Cheaper too (as they were built out of reference designs from parts suppliers).
Later on, we pushed these around on alibaba, and shoved them to our friends and colleagues as gifts. The funniest thing was, one of these colleagues took them to his factory to be cloned for cheap, and the last we heard, he’d sold tens of thousands of them overseas.
Another lesson learned: what’s already hot probably won’t be hot for you anymore by the time you finish playing catch-up, unless yours are cheaper or better than theirs in a big way, or marketed / sold in some brand-new way.
The S5 was a new loudspeaker model built on the “success” of the S3. Main features were the addition of an OLED display, internal storage, FM radio and an internal Li-ion battery.
Thus the S5 came with everything for the user to get started immediately, and the OLED display brought an immense improvement in operational convenience. The S5 also featured a small footprint and a high-end UV-cured paint coating in red or white for a sleek minimalist look. Put all these together and the S5 was well received by the market.
Unfortunately, as with the S3, its success attracted droves of clones and lookalikes at a fraction of its price. At the end, the S5 only barely paid for itself.
Thus, the PS1120 could sell no more, owing to its tie-in with a practically defunct product. But aside from docking with Meizu mp3 players, the PS1120 could also function as a bog-standard loudspeaker with 3.5mm line input, and those still get sales on the market… so to salvage some use for the tooling done for the PS1120, we took out the docking components, covered the hole with a logo, and this, plus a few simplifications here and there, was our S9 USB / AC powered speakers.
From our difficult time producing loudspeakers, we concluded that there’s little point being a pioneer in a mainstream market, as we were too small to make an impact and go on to dominate such a market, no matter how good our product may be. Other, bigger companies would simply copy our ideas and then outsell us. Better to reserve our pioneering effort to a more niche market.
Even so, through these misadventures, we gained significant experience, put together our own team and supply chain, so it was not all for naught.
The E7 was our third headphone amplifier after the E3 and E5, built around the same TI TPA6130 amplifier IC as the E5. What the E7 brought to the table was USB decoding using the TI PCM2706 USB receiver and Wolfson’s WM8740 DAC.
Starting from the E7, you may notice that we have put more emphasis on the continuity of product design and development of a hardware platform. The E7 started from known territory in the PCM2706, and the WM8740 was also used in many subsequent FiiOs.
Building on the same chip does not signify stagnation, however; on the contrary, what is built *around* the chips counts for 90% of the final performance of the units, and by building around the same chips for several product cycles, we could translate our accumulating experience into real tangible improvements in circuit design and avoid actual performance issues in designing around the latest new chips on the block.
The E7, with its reasonable price, rich connectivity and deluxe glass-fronted metal build found a home in many headphone audiophiles worldwide.
The E1 was FiiO's 4th amplifier product, and also a very interesting device. It is an amplifier with in-line remote control, specially made for the iPod and iPhone. The E1 gets its power supply and receives the iDevices' line out signal by connecting to their 30-pin dock then amplifies and outputs the audio signal from the headphone port.
The E1 also supports in-line remote control functions, making it possible to play/pause and change volume on the E1.In this way, even iPods that didn't support in-line remote control from its headphone port could now be remote controlled.
The same went for HiFi headphones without in-line remotes—they also gained remote control, giving users good user experience as well as good sound.
The E1 was welcomed by the market soon after its release, especially overseas. There are several reasons for its high popularity: 1. It was specially made for Apple products. 2. It improved the sound quality and user experience. 3. The price was quite reasonable (with retail price at 20 something USD). 4. Lastly, there was no similar product on the market at that time. As such, sales of the E1 boomed and enabled us to expand FiiO's coverage to many chain stores that were originally beyond our reach.
Unfortunately, starting from the iPhone 5, Apple changed the 30-pin dock to the new encrypted 8-pin Lightning dock, and the encryption, backed by the threat of litigation, prevented 3rd party accessories from being developed by any third party without Apple's authorization. We have been applying for MFi certification since 2008, without success. As a result, the E1 was discontinued 2 years later.
BTW, a major Japanese company later developed a similar product with exactly the same function.
The S5K was FiiO’s 12th product. It’s the upgraded version of the S5, with added support for reading micro SD cards based on the feedback of customers.
At that time, card-reader-boomboxes were already extremely popular, with hundreds of brands launching such products. I’d give examples, but you wouldn’t remember any of them anyway… It formed an enormous market; a factory with a popular model could sell a hundred thousand or even a million boxes per month, with large quantity shipped to overseas markets. A me-too production chain had developed; design houses produced the software and circuit board design, plastics factories and industrial design companies cooperated on the exterior design and provided reference mould toolings, driver companies provided the speaker units, while assembling factories (which may nominally brand the products) were responsible for nothing more than putting the pieces together. The finished products would then be sold to computer malls nationwide, or to overseas markets via trading companies.
Under such a me-too “knock-off” production model, with huge production volumes for every part / component, companies could offer rock bottom prices and release new products even every single week. Therefore, our business model of vertically integrating and overseeing all the procedures, from ID modeling, shell moulding, circuit design, to acoustic tuning to assembling, met a great challenge. Owing to high R&D cost, long R&D cycle and relatively low brand awareness, the S5K sank under the weight of the “critic’s corollary of Sturgeon’s Law” into complete anonymity.
Of course, Sturgeon’s Law being in full force over such a market, 90% of everything produced by this distributed manufacturing model turned out to be junk, 99% of all such boom boxes sold turned out to be junk (since junk sells cheaper), and finally, 99.9% of customers (along with FiiO ourselves) wrote off the entire segment as a complete waste of time and money.
In the sequence of FiiO products, S1 comes in at number thirteen, which is deemed an unlucky number, a presage for its market prospects. Another thing worth mentioning is that the S1 is FiiO’s very first OEM’ed model, meaning that the design and production were completed by other companies, while just branded with the FiiO logo.
Still, the S1 is quite unique in design—ultra thin and small, with built-in and rechargeable lithium battery. It is a single-channel design, with a 1" full-range driver with a powerful neodymium-iron-boron magnet. It is very convenient to carry outside along with your smartphone or DAP as an external speaker.
As a result, the sales of the S1 were quite poor. Only a few units were sold to the domestic market, while 1-2 thousand units were sold overseas. It beat a hasty retreat after 2 batches of production.
TheE9 was a desktop docking headphone amp specially designed for our portable DACs/ amps. As we mentioned before, our very first product was the dock /loudspeaker PS1120 for Meizu players; therefore, we consciously added docking support to many of our products; the E9 was the first dock to take advantage of this.
TheE9 was designed with two main purposes in mind: one is for use as a desktop headphone amp, to drive high impedance or low efficiency full-sized headphones.The other was for use as a dock for our players or portable DACs; together they become a full-sized component HiFi system with USB decoding. The portable DAC works as the source for the whole system and can be charged by E9 at the same time.
We see lots of products with this kind of design in Apple peripherals, such as docking loudspeakers. The release of E9 indeed improved the sales of our DACs.Meanwhile, the E9 itself, as a high-performance desktop headphone amp, was very competitive at its reasonable price.
The S10 is our last loudspeaker product, still based on the original PS1120. On the basis of the original appearance and structure, we replaced the 4 AA batteries with a rechargeable Li-polymer battery and added FM radio and MP3 playback functions.It also supported micro SD cards, infrared remote control and added a 2.4” TFT color display. So basically it’s a mini desktop audio system.
But we had decided, before the product was completed, that this should be our last loudspeaker product. The product line was abandoned and domestic sales operations for the line terminated, so we could focus our energy on the overseas market and headphone amps. Thus this loudspeaker was regrettably discontinued after 200 units’ trial production.
Looking back,starting from the PS1120 for the Meizu M6, to the exported M-dock loudspeaker(customized export model for Meizu), to versions supporting the M3 and M6 Slim,the S9 and finally the S10. We had poured painstaking effort into this product line and it had supported our initial business. Though we didn’t get much profit from these products, they laid a foundation from which our company eventually took off.
Finally, it’s worth mentioning that although the S-series ended on the S10 at FiiO, another company eventually bought the mold tooling for these elegant boxes with high quality finish, and remade the product into a Bluetooth boom box, sold internationally. Thus the shape of the S-series became something of an icon,being the base shape for the most number of different products associated with FiiO.
The sixteenth product D3 was developed based on market demand, and embodied our principles of product development-listening to user needs and market demand. It also spoke volumes for the fact that product demand varies between different countries and regions.
The D3 functions simply as a DAC, converting the digital PCM music signal from the Coaxial/ SPIDF in port into left & right stereo signal, and outputting the signal through the RCA port. The D3 was a compact unit, with clean lines and an all-metal chassis in sanded / anodized black finish. Utilizing a high-end Cirrus Logic DAC, the D3 had way better sound quality than similar competing products in the market at the time.
D3 made a hit in the US market. At the height of its popularity, its sales once ranked within the top 50 among all electronic devices sold in Amazon.
In conclusion, D3’s success formula was simple. Firstly, televisions sold in the US market at the time didn’t come with analog output interface anymore, while many families’ stereo systems continued to require analog input. In order to transmit the audio signal from TV to loudspeaker, they had to buy a product like the D3. Secondly, the D3 was one the only product that supported 192K/24B format at the time. Thirdly, competing products had lower performance and poorer function but over 30% higher price than the D3. Obviously the D3 was the best offering.
To this day, D03’s iterative upgrades continue to sell well internationally, although competition from similar products or even counterfeit D3’s is much more keen these days.
The 17th FiiO product is the E6, launched in July 2011.
We have introduced many products so far, all of which have been retired from our product lines. The E6 is different--it is still selling today, and has sold more than anything else we have sold to date. The E6 can be called a hero of FiiO.The E6 was released as the replacement to E5. It’s a giant leap in manufacturing craftsmanship, utilizing ultrasonic welding in assembly, and equipped with a transparent detachable clip. You can clip the E6 on your belt / shirt / etc. or remove the clip to stack the E6 with your player or mobile phone.
A1 had been well planned at the time we were manufacturing E7. What we meant to do is combining E7, E9 and A1 to compose an integrated sound system for both indoor and outdoor use. That’s to say we can use E7 as a portable headphone AMP outside and docked it with E9 to charge and work as a DAC home. If you still want to use your headphone then you can plug it in E9, or you can have A1 work as a mini digital amplifier to drive loudspeaker box.
So you might guess that logically there would be accompanying loudspeaker boxes coming out. Unfortunately, our brand was more known by headphone audiophiles, so our products that have nothing todo with headphones had always been unmarketable. A1 was discontinued after not too many productions.
Finally let me give you a brief introduction about A1. A1 is a mini Amp with full aluminum alloy shell. Its output power is 14w+14w, high enough to drive most of the desktop loudspeaker boxes. It adopts digital amplifier design and is featured by high efficiency,strong bass and clear voice. In addition, the price of A1 is affordable.
We’ve been hoping to build up connections between our products while making them. It’s something like Xiaomi’s hardware eco-chain. Regrettably we aren’t strong enough and our major products aren’t influential enough so far. Maybe in the future we can develop more peripherals when our players succeed.
Our 18th product was another classic.
2011was the year when we abandoned the loudspeaker product line and initiated our strategic focus. That focus is on portable audiophile products.
As you all know, from E1 and E3 to the E5 and E6, our headphone amplifiers were micro-sized and suitable for entry-level portable music lovers more than audiophiles. (except for the Chinese market, which seems to demand brick-sized products requiring a work out to carry at any price point…) Therefore, the market was calling for a portable headphone amplifier with better sound quality and stronger output power.
After one year of research and development, we launched the mid-range audiophile-class portable headphone amplifier E11 in May 2011. It became a hot-selling item and sold well until 2015, when it was replaced by the E11K and now the A3.
Compared to many DIY products in the market at the time, the E11 is distinctive. It retailed for 60USD,which was in a relatively unpopulated price bracket. So E11 was naturally sought after by our customers at the time of its release. Probably from the E11 on, the demand for our new products has always exceeded our supply. We have to experience months of ramping up to gradually meet the market demand.
The E11 applied a sandwich structure that rarely appears on headphone amplifiers. The top and the bottom covers are made of aluminum alloy while the middle frame is plastic. It came with a replaceable battery which is compatible with NOKIA phones. You could replace the battery by opening the top cover. In addition, a guard frame was introduced to protect the volume knob from inadvertent turns.
As for the circuit design, the E11 adopted a triple-channel design which can effectively lower the output impedance from ground wire and improve the left-right channel separation. The AD8397 opamp was applied to the left and right channels; this IC is very strong in current output and particularly suitable for headphone amplifiers. After the great success on the E11, we applied this design into subsequent products like the E17, X3 and E10, which were all well received.
The E11 was also equipped with our latest bass boost technique and supply voltage regulation function, so that it could provide more different timbres to consumers and better drive various headphones.
In virtue of its look, design, functions, sound quality and price advantage, the E11 soon became a best seller among its price bracket of medium-priced headphone amplifiers. It also had a great improvement in sound quality compared to our E5 and E6. It was recognized by more consumers in China at long last and became the backbone of our sales there.
FiiO’s nineteenth product is a USB decoder D5. It was designed for home use and couldbe used as an external mini USB sound card of laptops. The development was intended to complete a separate product line of Series D which is for average consumers.
The functions of D5 were simpler compared with other products in our company. It supported USB input, PO, LO, microphone input and coaxial output.
The positioning of D5 was not that accurate and therefore led to a dilemma: audiophile shardly had interest in it and ordinary consumers had no needs for it. It didn’t have an exact consumer group like D3 and the market feedback wasn’t satisfactory. At last, we discontinued the D5 after only two batch of production.
However,we found something interesting in it. Back In 2011, we were already known in the industry and had our distribution channels and sales agents in major markets all over the world. We found that we could sell a certain quantity of whatever new products. At least we could earn back the expenses on development. So no wonder those big companies can hardly restrain their desire to expand product lines. Because the risk of failing a new product is much lower and it’s not difficult to have the investment paid out so long as the product is barely satisfactory.
FiiO’s 20th product is E10, it’s also a classic work from us. E10 combines the AMP with AD8397 core used in E11 and the DAC with WM8740 core used in E7 , forms a mini USB DAC AMP. As the tuning style meets the requirement of foreign users, it was accepted and recommended by many audio celebrities. For example, Mike from Headfonia loves E10 very much. So it was warmly welcomed in the market after launching, and became a classic hot selling model of us.
What’smore important is that E10 is a connection link for the technology development.The development of E10 built a good foundation for the coming products E17 and X3. In fact, the AMP electric circuit cores of E11, E10, E17, X3 are the same, the DAC electric circuit cores of E7,E10,E17,X3 are the same as well. This makes us know about the potentials and features of the chips. Meanwhile, this makes sure there are no product quality problems from the source, so our product has been always very stable and excellent.
When the time came to 2012, FiiO has been founded for nearly 5 years. Basically, our company has put forward the main direction which aiming at the portable AMP market. The sale was growing well in oversea market.
In fact, we had a plan to develop a portable music player on the basis of E7 at 2011 and completed some preliminary work. But it was abeyant for some reason. In this condition, in order to enlarge the income, we had to expand the product line and enhanced the market share with the new products. So, we launched a portable AMP E17 with better feature and sound quality on the basis of E7.
E17 has relatively comprehensive features,can support the 96K/24B USB input and 192K/24B COAX input. Also it can be used as a pure AMP. It adopts the TE7022 USB input port chips from Taiwan. And theDAC chip is WM8740, AMP is AD8397 same as E11. It supports the desktop devices as well. It can work with E9 as a desktop DAC& system.
E17 inherited the mature and toning of a series of prior products, has more powerful features and became more mature and stable in quality. The sound is more suitable for the customers. It won a good reputation as soon as it released to the market, and became the main model of our product line. The sale value was the best among all the products as it had good selling and high price.
More important is that the price of E17 crossed 100 US dollars. This proved that we can win the market in the high price area. E17 improved the brand image and brand value of FiiO, and established a good basis for to get into the main market of HIFI in the future.
What’s interesting if that the customer in China started paying attention to FiiO products. Some Chinese customers started accepting and appreciating our products and became a loyal FiiO fan.
FiiO’s 22th product is E02i. We had designed a portable AMP E1 which was special used for iPhone and connected via 30 PIN connector. But Apple changed the 30 PIN port into the 8PIN lighting port from the model iPhone5. So we had to stop the production of E1.In this condition, considering we didn’t get the MFi certification from Apple,we started paying attention to the headphone output. In fact, the headphone output of iPhone and it supports the in-line remote as well. So we thought it’s a good idea to design a in-line remote portable AMP connected to the PO jack.
E02i was designed in this background.Different from its predecessor, the headphone output doesn’t support the power supply. So the E02i has the internal lithium battery. And it’s charged by USB cable. It supports the in-line remote like volume control, play/pause, next track/previous track. The output power increased 3 times than iPhone itself.The whole body is covered by aluminum alloy shell, a back clip is attached also. The shining aluminum in-line remote key is processed with the CD stripe.There’s a beautiful light circle around it as well.
The market response is average. After one year’s production, as we had entered the player industry, in order to reduce the difficulty of production management, we stopped manufacturing E02i. And this is the end of the in-line remote AMP special for iPhone like E1/E02i.
FiiO’s 23rd product G1 is a special model, because it’s a portable AMP designed for guitar. In US/UK,almost every young people play with guitar. But the electronic guitar is different with the classic (wooden guitar), it needs the amplifier. Usually, they use speaker when they play in the show. But if they practice at home, they need a AMP to avoid the influence to family and neighborhoods.
So there’s a considerable market in US for guitar AMP. Certainly, the style and features seem very old and in question because there’s no Chinese competitor.
1. Because every guitar AMP has a 6.3 plug, it very big.
2. Most guitar AMPs use the dry battery for power supply.
So we attempted to design the guitar AMPG1. The plug can be folded so that it easy to carry and store. We replace the dry battery with the rechargeable lithium battery. In other aspects, we kept the functions of volume control, motivation and the effect adjusting.
At last, because there’s no big inter section between the traditional FiiO users and the guitar AMP users, and there are some strong competitors in US market. Even a small guitar has more than ten models with different colors. So our G1 didn’t help us to develop the new market, new products and new customers.
I have introduced that our D3 is so popular in America market because the LCD TVs don’t have analog audio output. So people need a D3 to connect the LCD TV with the old music system at home. But we received some feedbacks; some of the digital programs are multichannel surround sound system. Especially for the high definition all adopt the Dolby multichannel audio encoding format. And D3 is helpless about this.
So, in order to satisfy the customers for their requirements, we developed a little multichannel decoder D7. It adopts ESS semiconductor chip, aluminum alloy shell, coaxial and optical input,standard 5V USB power supply, standard RCA and 3.5mm stereo analog audio output and the analog audio output by which multichannel Dolby /DTS signal can be transferred to 2nd channel.
E12 is out our plan, there is not this model in our former product map. The main reason is that the portable audio enthusiastic products have a small market. No one wants to go outside with a bundle. So we don’t think the high-end portable AMPs (price over 100 USD, which is 650RMB)have a good future.
But as the products like E11,E17 are hot in the market, we view and assess the market again. According to the communication and survey with the customers, we found the customers buy portable AMPs not only for outdoor using, they also desire portability indoor very much. And the desktop AMP is not suitable for moving. In the other hand, there’s no big brand get into this area in the market, so the market is lack of the high quality, high cost performance, high performance and high output powerAMP.
FiiO is a customer oriented company, as the customers have the demands, and the demand is available in business, then we will do it. So the E12 was born.
In order to get higher voltage, E12 adopt 3 lithium battery connected in series to get 11V voltage, and use the way of DC/DC transfer to get the minus 11V voltage. We get total 22V voltage(plus-minus 11V voltage). Thus, the output power is stronger than the AMPs use the 9V battery, and the thickness was decreased to comparatively thin.
As the E12 has higher voltage, and it adopts the metal sealed LEM49600 audio op-amp, the output power reached 850mW each channel. This output power can be comparable with many desktop AMPs.
E12 adopts the best op-amp of TI, the OPA1611 to enhance the voltage and metal sealed LME49600 to enhance the electric current. And it adopts the ALPS audio taper and WIMA HIFI capacitance from Germany, etc.
In the other hand, compared with other AMPs, E12 improved so much user experience, like the fast smart charging,indicator light with breathing effect and improved the crossfeed features.
E12 get the buzz and loved in the market. In domestic market, E12 is also the best seller among all of our products. It’s better than de low level model E11. As the customers love this model so much, we derived the souvenir edition E12DIY (audio op-amp is replaceable) and the E12IEM for ear buds.
The 27th product is a characteristic DAC&. The Android started supporting the USB decoding from Android 4.1. And we didn’t get the approval of MFI, it’s very disappointed that we can not develop the DAC& for iPhone. So we can only develop aDAC& for Android phone.
In fact, the previous models like E7, E17also support some Android phones. But E7 and E17 are charged via USSB port. So it will cause many problems about compatibility. Even it’s compatible, the DAC& will get power from USB port of phones, it will make the battery life of phones short.
1. E18 has the mobile phone decoding model. In this model, the power supply is from the battery inside it only, and will not consume the power from mobile phone.
2. E18 has the features for controlling play/pause, previous/next track by the DAC& itself. All the mobile phones support the USB decoding obey the USB audio rules, so we can do some operation of the music playing APP via the key on the DAC&.
3. E18 can be used as the power pan as there’s a big battery inside.
4. Compared with E7 and E17, we improve so much about the compatibility, so it can support more models of Android phones.
But we found the sale of E18 is not so optimistic after launching. The main reason is that we cannot solve the problem of listening to a call when we bundle the DAC& with the phone. So most people are not willing to bundle a AMP for listening music except few. In fact,most enthusiastic fans are more willing to choose a player for resource.Another problem is about compatibility. Include that the mobile phone cannot be connected because of the difference of hardware or firmware. Though it’s not the problem of E18, but to 99.9% factories, weather the mobile phone support the USB audio output or not, it’s not a problem worth serious and careful treatment. This limits the sale of E18 also.
Of course, as a meaningful attempt, a lot of customers love E18 very much. We wanted to stop this model once. But some customers call on continue manufacturing and selling E18. Though the people who bundle AMPs with mobile phones are few, but they are our loyal customers, we should fulfill their requirement anyhow.
The 26th product X3 is a milestone in FiiO history. Start from X3, the development of FiiO came to a new stage and we opened another gate for the future. It’s also a iconic product that makes FiiO return back to the domestic market. Meanwhile, it perhaps changed the situation of the industry.
X3 is a portable audio player which can support 192K/24B sample frequency and bit depth, non-native DSD decode, common lossless music format such as ALAC/APE/FLAC/WMA/WAV, etc and also some lossy music format like OGG, ACC, MP3 etc. Also, when it’s connected to the computer,it can work as an asynchronous 192K/24B USB DAC.
For the features and the formats it can support, X3 can defeat all the similar models in the market. X3 is smaller in size and lighter in weight, and the UI is closer to public products. Compared with The Brick, the output power is equal. More important is that the prices of the similar models are very high, but the X3 break the price range with the price of 1298 RMB. So it gained maximum attention and purchasing upsurge as soon as it released to the market.
Now, let’s check the records that X3 has made together.
Longest time in development, X3 project was started in 2009, but the trail sale started in June 2013.
Most users are involved into the discussion, we started asking for suggestions in Head-fi the biggest community of headphone enthusiastic fans in the world when we set up the project. The post got clicked and read by millions of times, more than ten thousand replies last more than one thousand pages.
The price was the lowest for 192K/24B portable music player at that time. The 1298RMB price was the sighting, and many competitors set the price around it.
X3 was the smallest and lightest of the players made in China with equal output power. The output power is about 550mW when impedance is 16 Ohm. This output power is not weaker than the similar product with one or two grade higher price. But it’s demission is 50*109*16mm,and weight is 122g.
The X3 project was set up in the autumn of 2009. We have launched E17and completed the design of E7. The next step is to add the main control decode and develop the portable music player on the basis of E7. So, different with many people guessed. We didn’t follow the market blindly because others sell well. But, we had logic and previous plans of procedures.
At that time, the user experience of the portable music player for enthusiastic fans is not so good. They were heavy and big, so they were called The Brick. And because of the operation stratagem of other competitors, they gave us much space for price setting.
We can say that it’s obvious that X3 will be hot when it was launched in the market, because we aimed at the weakness of the competitors and advantage of itself.
In fact, except the special offer activity and the advantages of the product, good service is also the key for the success of X3.
1. We released new features continuously. X3 got 3 important improvements after launching by upgrading the firmware. Include USD DAC supporting, DSD decode supporting and all new UI graph interface. The former 2 upgraded features are advance in the industry. The last upgraded feature showed that we are responsible for our customers.
2. We optimized the system and repaired the BUGs by upgrading the firmware. Also we added more humanized features and improved the stability and speed of the system.
3. We designed many accessories for X3,such as leather covers, color silica covers, rinsing covers, binding parts,bags and so on. Of course, we are the first manufacturer who stick the screen guards and provide the silica covers when the products come out from the factory. In fact, few manufacturers can be so considerable and perfect as us,because this cost so much.
In addition, we never stop innovating in marketing. We provided the favorable combination by cooperative with DNK and Beyerdynamic. We held the tour audition and tail mall free audition. These innovative services and marketing activities helped the customers find the way to listen to our products, and buy them.
We have to say that X3 had taken the advantage in market. Within half an year after X3 was launched, many similar product came out. Their price was eye for eye with us, and changed the image of The Brick in features and performance. We can imagine that we cannot raise the hot wave and got the same popularity among the enthusiastic fans if we didn’t take the advantage in the market of 1000RMB class.
At last, I thank the old users of X3 by this chance. There are many disadvantages in design, modeling, manufacture,user experience, and UI because it was the first generation of players. Though we did many feedback activities to the old customers, but it’s not enough to express our thanks. Thank you for all your understanding and supporting again.
FiiO’s 31st product is also an upgrading model E10K. We intended to cut down the product line after we sold good in the player market. E10 was also in the elimination list. But the market appeals to us, so we launched the upgrading product to feed back the customer sand distributors support us.
The sale is good after E10 launched. But E10 is positioned to be a desktop product, it has no its own battery. So the sale is not good as the portable DAC$AMP like E17 and E7.
So we intended to discontinue the E10.When we published this news, some distributors feed back that many customers want such a product can be chosen. Though E10 cannot bring us much profit, but we always put the customer in the first place. So we upgraded on the basis of E10 and brought out E10K.
The biggest improvement of E10K is that we changed the USB receiving chip. And we changed the abused WM8740 to semi-conductive PCM5102 from American TI Company. The amplifier is also changed to LMH6643 same as X5/E11K to improve the performance. Compared with the predecessor E10, the sound is not so dignified and warm, but it’s more balanced and modern.
Other improvements only influenced a little in user experience, like the headphone jack was changed to the one we ordered when we start the model. The background noise is smaller and the delay of mute circuit when we change the track is improved.
Of course, every product has the end in the product circle. We got good sale of E10K in American market, but the contribution rate is smaller and smaller as the company grows. Maybe E10K will disappear in our product line.
X3 is the first portable music player of FiiO, and it has made a great contribution to make FiiO to be at the third place in market share after Apple and Sony.
But, we started the design of X3 in 2009 after all. There are many imperfections in appearance design, workmanship, man-machine interaction and UI. So we started the design for new X3 when we designed the X1.
Compared with the old X3, the X3II is improved overall except the output power is a little lower.
We added the DSD native decoding function to X3II. Because the master control is not in charge of DSD decoding any more, the X3II can support the DSD128 format and Blue-ray SACD image file in ISO format. This improved the DSD sound quality and solved the hanging problem for non-native DSD decoding. It’s more convenient that they don’t need to transfer the format as the X3II can support more formats.
X3II has the new function of deep standby model. Popularly speaking, we have improved the hardware design, so the standby current is very low. So the users don’t need to turn it off after listening music. And don't need to wait when it change to operative mode from standby mode. We are the first Chinese brand to improve this user experience.
For sound quality, the X3II replaced WM8740 with CS4389 chip which can support DSD native decoding. Compared with WM8740, the performance of CS4389 is better, and is more high-fidelity. We changed amp circuit from AD8397 to combination of OPA1642 and LMH664 produced by TI Company in America. We enhanced the definition and sound stage, and kept the warm one the basis of warm and fashionable sound.
X3II followed the design of X1 for appearance and UI. The back cover was changed to aluminum alloy. And it’s thicker than X1 because of it needs the larger battery to provide higher power. We also improved some other texture details. Like the key was made of metal, we added diamond effect to the frame, we used more match color with strong texture for the theme.
Of course, if the resource is enough for us. We’d like to make a new rather than use the same design as X1. But the good design is hard to get, We cannot put forward many new designs loved and welcomed by the customers in such a short time.


This article is about water ice. For the broader concept of "ices" as used in the planetary sciences, see Volatiles. For other uses, see Ice (disambiguation).
Ice molecules can exhibit eighteen or more different phases (packing geometries) that depend on temperature and pressure. When water is cooled rapidly (quenching), up to three different types of amorphous ice can form depending on the history of its pressure and temperature. When cooled slowly correlated proton tunneling occurs below 7001199999999999999♠−253.15 °C (7001200000000000000♠20 K, 7001199999999999999♠−423.67 °F) giving rise to macroscopic quantum phenomena. Virtually all the ice on Earth's surface and in its atmosphere is of a hexagonal crystalline structure denoted as ice Ih (spoken as "ice one h") with minute traces of cubic ice denoted as ice Ic. The most common phase transition to ice Ih occurs when liquid water is cooled below 7002273149999999999♠0 °C (7002273149999999999♠273.15 K, 7002273149999999999♠32 °F) at standard atmospheric pressure. It may also be deposited directly by water vapor, as happens in the formation of frost. The transition from ice to water is melting and from ice directly to water vapor is sublimation.
The three-dimensional crystal structure of H2O ice Ih (c) is composed of bases of H2O ice molecules (b) located on lattice points within the two-dimensional hexagonal space lattice (a).
As a naturally occurring crystalline inorganic solid with an ordered structure, ice is considered to be a mineral. It possesses a regular crystalline structure based on the molecule of water, which consists of a single oxygen atom covalently bonded to two hydrogen atoms, or H–O–H. However, many of the physical properties of water and ice are controlled by the formation of hydrogen bonds between adjacent oxygen and hydrogen atoms; while it is a weak bond, it is nonetheless critical in controlling the structure of both water and ice.
An unusual property of ice frozen at atmospheric pressure is that the solid is approximately 8.3% less dense than liquid water (which is equivalent to volumetric expansion of 9%). The density of ice is 0.9167–0.9168 g/cm3 at 0 °C and standard atmospheric pressure (101,325 Pa), whereas water has a density of 0.9998–0.999863 g/cm3 at the same temperature and pressure. Liquid water is densest, essentially 1.00 g/cm3, at 4 °C and becomes less dense as the water molecules begin to form the hexagonal crystals of ice as the freezing point is reached. This is due to hydrogen bonding dominating the intermolecular forces, which results in a packing of molecules less compact in the solid. Density of ice increases slightly with decreasing temperature and has a value of 0.9340 g/cm3 at −180 °C (93 K).
When water freezes, it increases in volume (about 9% for fresh water). The effect of expansion during freezing can be dramatic, and ice expansion is a basic cause of freeze-thaw weathering of rock in nature and damage to building foundations and roadways from frost heaving. It is also a common cause of the flooding of houses when water pipes burst due to the pressure of expanding water when it freezes.
The result of this process is that ice (in its most common form) floats on liquid water, which is an important feature in Earth's biosphere. It has been argued that without this property, natural bodies of water would freeze, in some cases permanently, from the bottom up, resulting in a loss of bottom-dependent animal and plant life in fresh and sea water. Sufficiently thin ice sheets allow light to pass through while protecting the underside from short-term weather extremes such as wind chill. This creates a sheltered environment for bacterial and algal colonies. When sea water freezes, the ice is riddled with brine-filled channels which sustain sympagic organisms such as bacteria, algae, copepods and annelids, which in turn provide food for animals such as krill and specialised fish like the bald notothen, fed upon in turn by larger animals such as emperor penguins and minke whales.
When ice melts, it absorbs as much energy as it would take to heat an equivalent mass of water by 80 °C. During the melting process, the temperature remains constant at 0 °C. While melting, any energy added breaks the hydrogen bonds between ice (water) molecules. Energy becomes available to increase the thermal energy (temperature) only after enough hydrogen bonds are broken that the ice can be considered liquid water. The amount of energy consumed in breaking hydrogen bonds in the transition from ice to water is known as the heat of fusion.
As with water, ice absorbs light at the red end of the spectrum preferentially as the result of an overtone of an oxygen–hydrogen (O–H) bond stretch. Compared with water, this absorption is shifted toward slightly lower energies. Thus, ice appears blue, with a slightly greener tint than liquid water. Since absorption is cumulative, the color effect intensifies with increasing thickness or if internal reflections cause the light to take a longer path through the ice.
"Ice IV" redirects here. For the high speed train, see ICE 4.
"Ice X" redirects here. For other uses, see Icex (disambiguation).
Ice may be any one of the 18 known solid crystalline phases of water, or in an amorphous solid state at various densities.
Most liquids under increased pressure freeze at higher temperatures because the pressure helps to hold the molecules together. However, the strong hydrogen bonds in water make it different: For some pressures higher than 1 atm (0.10 MPa), water freezes at a temperature below 0 °C, as shown in the phase diagram below. The melting of ice under high pressures is thought to contribute to the movement of glaciers.
Ice, water, and water vapour can coexist at the triple point, which is exactly 273.16 K (0.01 °C) at a pressure of 611.657 Pa. The kelvin is in fact defined as 1/273.16 of the difference between this triple point and absolute zero, though this definition is due to change in May 2019. Unlike most other solids, ice is difficult to superheat. In an experiment, ice at −3 °C was superheated to about 17 °C for about 250 picoseconds.
Subjected to higher pressures and varying temperatures, ice can form in 18 separate known crystalline phases. With care, at least 15 of these phases (one of the known exceptions being ice X) can be recovered at ambient pressure and low temperature in metastable form. The types are differentiated by their crystalline structure, proton ordering, and density. There are also two metastable phases of ice under pressure, both fully hydrogen-disordered; these are IV and XII. Ice XII was discovered in 1996. In 2006, XIII and XIV were discovered. Ices XI, XIII, and XIV are hydrogen-ordered forms of ices Ih, V, and XII respectively. In 2009, ice XV was found at extremely high pressures and −143 °C. At even higher pressures, ice is predicted to become a metal; this has been variously estimated to occur at 1.55 TPa or 5.62 TPa.
As well as crystalline forms, solid water can exist in amorphous states as amorphous ice (ASW) of varying densities. Water in the interstellar medium is dominated by amorphous ice, making it likely the most common form of water in the universe. Low-density ASW (LDA), also known as hyperquenched glassy water, may be responsible for noctilucent clouds on Earth and is usually formed by deposition of water vapor in cold or vacuum conditions. High-density ASW (HDA) is formed by compression of ordinary ice Ih or LDA at GPa pressures. Very-high-density ASW (VHDA) is HDA slightly warmed to 160K under 1–2 GPa pressures.
In outer space, hexagonal crystalline ice (the predominant form found on Earth) is extremely rare. Amorphous ice is more common; however, hexagonal crystalline ice can be formed by volcanic action.
Log-lin pressure-temperature phase diagram of water. The Roman numerals correspond to some ice phases listed below.
Ice Ic A metastable cubic crystalline variant of ice. The oxygen atoms are arranged in a diamond structure. It is produced at temperatures between 130 and 220 K, and can exist up to 240 K, when it transforms into ice Ih. It may occasionally be present in the upper atmosphere.
Ice II A rhombohedral crystalline form with highly ordered structure. Formed from ice Ih by compressing it at temperature of 190–210 K. When heated, it undergoes transformation to ice III.
Ice IV A metastable rhombohedral phase. It can be formed by heating high-density amorphous ice slowly at a pressure of 810 MPa. It does not form easily without a nucleating agent.
Ice VII A cubic phase. The hydrogen atoms' positions are disordered. Exhibits Debye relaxation. The hydrogen bonds form two interpenetrating lattices.
Ice VIII A more ordered version of ice VII, where the hydrogen atoms assume fixed positions. It is formed from ice VII, by cooling it below 5 °C (278 K).
Ice IX A tetragonal phase. Formed gradually from ice III by cooling it from 208 K to 165 K, stable below 140 K and pressures between 200 MPa and 400 MPa. It has density of 1.16 g/cm3, slightly higher than ordinary ice.
Ice XI An orthorhombic, low-temperature equilibrium form of hexagonal ice. It is ferroelectric. Ice XI is considered the most stable configuration of ice Ih.
Ice XII A tetragonal, metastable, dense crystalline phase. It is observed in the phase space of ice V and ice VI. It can be prepared by heating high-density amorphous ice from 77 K to about 183 K at 810 MPa. It has a density of 1.3 g cm−3 at 127 K (i.e., approximately 1.3 times more dense than water).
Ice XV The proton-ordered form of ice VI formed by cooling water to around 80–108 K at 1.1 GPa.
Ice XVI The least dense crystalline form of water, topologically equivalent to the empty structure of sII clathrate hydrates.
Square ice Square ice crystals form at room temperature when squeezed between two layers of graphene. The material was a new crystalline phase of ice, joining 17 others, when it was first reported in 2014. The research derived from the earlier discovery that water vapor and liquid water could pass through laminated sheets of graphene oxide, unlike smaller molecules such as helium. The effect is thought to be driven by the van der Waals force, which may involve more than 10,000 atmospheres of pressure.
The low coefficient of friction ("slipperiness") of ice has been attributed to the pressure of an object coming into contact with the ice, melting a thin layer of the ice and allowing the object to glide across the surface. For example, the blade of an ice skate, upon exerting pressure on the ice, would melt a thin layer, providing lubrication between the ice and the blade. This explanation, called "pressure melting", originated in the 19th century. It, however, did not account for skating on ice temperatures lower than −4 °C (25 °F; 269 K), which is often skated upon.
A second theory describing the coefficient of friction of ice suggested that ice molecules at the interface cannot properly bond with the molecules of the mass of ice beneath (and thus are free to move like molecules of liquid water). These molecules remain in a semi-liquid state, providing lubrication regardless of pressure against the ice exerted by any object. However, the significance of this hypothesis is disputed by experiments showing a high coefficient of friction for ice using atomic force microscopy.
A third theory is "friction heating", which suggests that friction of the material is the cause of the ice layer melting. However, this theory does not sufficiently explain why ice is slippery when standing still even at below-zero temperatures.
A comprehensive theory of ice friction takes into account all the above-mentioned friction mechanisms. This model allows quantitative estimation of the friction coefficient of ice against various materials as a function of temperature and sliding speed. In typical conditions related to winter sports and tires of a vehicle on ice, melting of a thin ice layer due to the frictional heating is the primary reason for the slipperiness.
The term that collectively describes all of the parts of the Earth's surface where water is in frozen form is the cryosphere. Ice is an important component of the global climate, particularly in regard to the water cycle. Glaciers and snowpacks are an important storage mechanism for fresh water; over time, they may sublimate or melt. Snowmelt is an important source of seasonal fresh water. The World Meteorological Organization defines several kinds of ice depending on origin, size, shape, influence and so on. Clathrate hydrates are forms of ice that contain gas molecules trapped within its crystal lattice.
Ice that is found at sea may be in the form of drift ice floating in the water, fast ice fixed to a shoreline or anchor ice if attached to the sea bottom. Ice which calves (breaks off) from an ice shelf or glacier may become an iceberg. Sea ice can be forced together by currents and winds to form pressure ridges up to 12 metres (39 ft) tall. Navigation through areas of sea ice occurs in openings called "polynyas" or "leads" or requires the use of a special ship called an "icebreaker".
Ice on land ranges from the largest type called an "ice sheet" to smaller ice caps and ice fields to glaciers and ice streams to the snow line and snow fields.
Freezing rain is a type of winter storm called an ice storm where rain falls and then freezes producing a glaze of ice. Ice can also form icicles, similar to stalactites in appearance, or stalagmite-like forms as water drips and re-freezes.
The term "ice dam" has three meanings (others discussed below). On structures, an ice dam is the buildup of ice on a sloped roof which stops melt water from draining properly and can cause damage from water leaks in buildings.
Ice which forms on moving water tends to be less uniform and stable than ice which forms on calm water. Ice jams (sometimes called "ice dams"), when broken chunks of ice pile up, are the greatest ice hazard on rivers. Ice jams can cause flooding, damage structures in or near the river, and damage vessels on the river. Ice jams can cause some hydropower industrial facilities to completely shut down. An ice dam is a blockage from the movement of a glacier which may produce a proglacial lake. Heavy ice flows in rivers can also damage vessels and require the use of an icebreaker to keep navigation possible.
Ice discs are circular formations of ice surrounded by water in a river.
Pancake ice is a formation of ice generally created in areas with less calm conditions.
Ice forms on calm water from the shores, a thin layer spreading across the surface, and then downward. Ice on lakes is generally four types: Primary, secondary, superimposed and agglomerate. Primary ice forms first. Secondary ice forms below the primary ice in a direction parallel to the direction of the heat flow. Superimposed ice forms on top of the ice surface from rain or water which seeps up through cracks in the ice which often settles when loaded with snow.
Shelf ice occurs when floating pieces of ice are driven by the wind piling up on the windward shore.
Rime is a type of ice formed on cold objects when drops of water crystallize on them. This can be observed in foggy weather, when the temperature drops during the night. Soft rime contains a high proportion of trapped air, making it appear white rather than transparent, and giving it a density about one quarter of that of pure ice. Hard rime is comparatively dense.
Ice pellets are a form of precipitation consisting of small, translucent balls of ice. This form of precipitation is also referred to as "sleet" by the United States National Weather Service. (In British English "sleet" refers to a mixture of rain and snow.) Ice pellets are usually smaller than hailstones. They often bounce when they hit the ground, and generally do not freeze into a solid mass unless mixed with freezing rain. The METAR code for ice pellets is PL.
Ice pellets form when a layer of above-freezing air is located between 1,500 and 3,000 metres (4,900 and 9,800 ft) above the ground, with sub-freezing air both above and below it. This causes the partial or complete melting of any snowflakes falling through the warm layer. As they fall back into the sub-freezing layer closer to the surface, they re-freeze into ice pellets. However, if the sub-freezing layer beneath the warm layer is too small, the precipitation will not have time to re-freeze, and freezing rain will be the result at the surface. A temperature profile showing a warm layer above the ground is most likely to be found in advance of a warm front during the cold season, but can occasionally be found behind a passing cold front.
Like other precipitation, hail forms in storm clouds when supercooled water droplets freeze on contact with condensation nuclei, such as dust or dirt. The storm's updraft blows the hailstones to the upper part of the cloud. The updraft dissipates and the hailstones fall down, back into the updraft, and are lifted up again. Hail has a diameter of 5 millimetres (0.20 in) or more. Within METAR code, GR is used to indicate larger hail, of a diameter of at least 6.4 millimetres (0.25 in) and GS for smaller. Stones just larger than golf ball-sized are one of the most frequently reported hail sizes. Hailstones can grow to 15 centimetres (6 in) and weigh more than 0.5 kilograms (1.1 lb). In large hailstones, latent heat released by further freezing may melt the outer shell of the hailstone. The hailstone then may undergo 'wet growth', where the liquid outer shell collects other smaller hailstones. The hailstone gains an ice layer and grows increasingly larger with each ascent. Once a hailstone becomes too heavy to be supported by the storm's updraft, it falls from the cloud.
Hail forms in strong thunderstorm clouds, particularly those with intense updrafts, high liquid water content, great vertical extent, large water droplets, and where a good portion of the cloud layer is below freezing 0 °C (32 °F). Hail-producing clouds are often identifiable by their green coloration. The growth rate is maximized at about −13 °C (9 °F), and becomes vanishingly small much below −30 °C (−22 °F) as supercooled water droplets become rare. For this reason, hail is most common within continental interiors of the mid-latitudes, as hail formation is considerably more likely when the freezing level is below the altitude of 11,000 feet (3,400 m). Entrainment of dry air into strong thunderstorms over continents can increase the frequency of hail by promoting evaporational cooling which lowers the freezing level of thunderstorm clouds giving hail a larger volume to grow in. Accordingly, hail is actually less common in the tropics despite a much higher frequency of thunderstorms than in the mid-latitudes because the atmosphere over the tropics tends to be warmer over a much greater depth. Hail in the tropics occurs mainly at higher elevations.
Snow crystals form when tiny supercooled cloud droplets (about 10 μm in diameter) freeze. These droplets are able to remain liquid at temperatures lower than −18 °C (255 K; 0 °F), because to freeze, a few molecules in the droplet need to get together by chance to form an arrangement similar to that in an ice lattice; then the droplet freezes around this "nucleus." Experiments show that this "homogeneous" nucleation of cloud droplets only occurs at temperatures lower than −35 °C (238 K; −31 °F). In warmer clouds an aerosol particle or "ice nucleus" must be present in (or in contact with) the droplet to act as a nucleus. Our understanding of what particles make efficient ice nuclei is poor – what we do know is they are very rare compared to that cloud condensation nuclei on which liquid droplets form. Clays, desert dust and biological particles may be effective, although to what extent is unclear. Artificial nuclei are used in cloud seeding. The droplet then grows by condensation of water vapor onto the ice surfaces.
So-called "diamond dust", also known as ice needles or ice crystals, forms at temperatures approaching −40 °C (−40 °F) due to air with slightly higher moisture from aloft mixing with colder, surface-based air. The METAR identifier for diamond dust within international hourly weather reports is IC.
Ablation of ice refers to both its melting and its dissolution.
In fresh ambient melting describes a phase transition from solid to liquid.
To melt ice means breaking the hydrogen bonds between the water molecules. The ordering of the molecules in the solid breaks down to a less ordered state and the solid melts to become a liquid. This is achieved by increasing the internal energy of the ice beyond the melting point. When ice melts it absorbs as much energy as would be required to heat an equivalent amount of water by 80 °C. While melting, the temperature of the ice surface remains constant at 0 °C. The velocity of the melting process depends on the efficiency of the energy exchange process. An ice surface in fresh water melts solely by free convection with a velocity that depends linearly on the water temperature, T∞, when T∞ is less than 3.98 °C, and superlinearly when T∞ is equal to or greater than 3.98 °C, with the rate being proportional to (T∞ − 3.98 °C)α, with α = 5/3 for T∞ much greater than 8 °C, and α = 4/3 for in between temperatures T∞.
In salty ambient conditions, dissolution rather than melting often causes the ablation of ice. For example, the temperature of the Arctic Ocean is generally below the melting point of ablating sea ice. The phase transition from solid to liquid is achieved by mixing salt and water molecules, similar to the dissolution of sugar in water, even though the water temperature is far below the melting point of the sugar. Hence dissolution is rate limited by salt transport whereas melting can occur at much higher rates that are characteristic for heat transport.
Humans have used ice for cooling and food preservation for centuries, relying on harvesting natural ice in various forms and then transitioning to the mechanical production of the material. Ice also presents a challenge to transportation in various forms and a setting for winter sports.
Ice has long been valued as a means of cooling. In 400 BC Iran, Persian engineers had already mastered the technique of storing ice in the middle of summer in the desert. The ice was brought in during the winters from nearby mountains in bulk amounts, and stored in specially designed, naturally cooled refrigerators, called yakhchal (meaning ice storage). This was a large underground space (up to 5000 m3) that had thick walls (at least two meters at the base) made of a special mortar called sarooj, composed of sand, clay, egg whites, lime, goat hair, and ash in specific proportions, and which was known to be resistant to heat transfer. This mixture was thought to be completely water impenetrable. The space often had access to a qanat, and often contained a system of windcatchers which could easily bring temperatures inside the space down to frigid levels on summer days. The ice was used to chill treats for royalty.
There were thriving industries in 16th–17th century England whereby low-lying areas along the Thames Estuary were flooded during the winter, and ice harvested in carts and stored inter-seasonally in insulated wooden houses as a provision to an icehouse often located in large country houses, and widely used to keep fish fresh when caught in distant waters. This was allegedly copied by an Englishman who had seen the same activity in China. Ice was imported into England from Norway on a considerable scale as early as 1823.
In the United States, the first cargo of ice was sent from New York City to Charleston, South Carolina, in 1799, and by the first half of the 19th century, ice harvesting had become big business. Frederic Tudor, who became known as the "Ice King", worked on developing better insulation products for the long distance shipment of ice, especially to the tropics; this became known as the ice trade.
Trieste sent ice to Egypt, Corfu, and Zante; Switzerland sent it to France; and Germany sometimes was supplied from Bavarian lakes. The Hungarian Parliament building used ice harvested in the winter from Lake Balaton for air conditioning.
Ice houses were used to store ice formed in the winter, to make ice available all year long, and early refrigerators were known as iceboxes, because they had a block of ice in them. In many cities, it was not unusual to have a regular ice delivery service during the summer. The advent of artificial refrigeration technology has since made delivery of ice obsolete.
Ice is still harvested for ice and snow sculpture events. For example, a swing saw is used to get ice for the Harbin International Ice and Snow Sculpture Festival each year from the frozen surface of the Songhua River.
Ice is now produced on an industrial scale, for uses including food storage and processing, chemical manufacturing, concrete mixing and curing, and consumer or packaged ice. Most commercial icemakers produce three basic types of fragmentary ice: flake, tubular and plate, using a variety of techniques. Large batch ice makers can produce up to 75 tons of ice per day. In 2002, there were 426 commercial ice-making companies in the United States, with a combined value of shipments of $595,487,000. Home refrigerators can also make ice with a built in icemaker, which will typically make ice cubes or crushed ice. Stand-alone icemaker units that make ice cubes are often called ice machines.
Ice can present challenges to safe transportation on land, sea and in the air.
Road ice decreases tire traction, thereby affecting driving safety.
When the outdoor temperature stays below freezing for extended periods, very thick layers of ice can form on lakes and other bodies of water, although places with flowing water require much colder temperatures. The ice can become thick enough to drive onto with automobiles and trucks. Doing this safely requires a thickness of at least 30 cm (one foot).
For ships, ice presents two distinct hazards. Spray and freezing rain can produce an ice build-up on the superstructure of a vessel sufficient to make it unstable, and to require it to be hacked off or melted with steam hoses. And icebergs – large masses of ice floating in water (typically created when glaciers reach the sea) – can be dangerous if struck by a ship when underway. Icebergs have been responsible for the sinking of many ships, the most famous being the Titanic. For harbors near the poles, being ice-free is an important advantage. Ideally, all year long. Examples are Murmansk (Russia), Petsamo (Russia, formerly Finland) and Vardø (Norway). Harbors which are not ice-free are opened up using icebreakers.
Rime ice on the leading edge of an aircraft wing, partially released by the black pneumatic boot.
For aircraft, ice can cause a number of dangers. As an aircraft climbs, it passes through air layers of different temperature and humidity, some of which may be conducive to ice formation. If ice forms on the wings or control surfaces, this may adversely affect the flying qualities of the aircraft. During the first non-stop flight across the Atlantic, the British aviators Captain John Alcock and Lieutenant Arthur Whitten Brown encountered such icing conditions – Brown left the cockpit and climbed onto the wing several times to remove ice which was covering the engine air intakes of the Vickers Vimy aircraft they were flying.
One vulnerability effected by icing that is associated with reciprocating internal combustion engines is the carburetor. As air is sucked through the carburetor into the engine, the local air pressure is lowered, which causes adiabatic cooling. Thus, in humid near-freezing conditions, the carburetor will be colder, and tend to ice up. This will block the supply of air to the engine, and cause it to fail. For this reason, aircraft reciprocating engines with carburetors are provided with carburetor air intake heaters. The increasing use of fuel injection—which does not require carburetors—has made "carb icing" less of an issue for reciprocating engines.
Ice also plays a central role in winter recreation and in many sports such as ice skating, tour skating, ice hockey, bandy, ice fishing, ice climbing, curling, broomball and sled racing on bobsled, luge and skeleton. Many of the different sports played on ice get international attention every four years during the Winter Olympic Games.
A sort of sailboat on blades gives rise to ice yachting. Another sport is ice racing, where drivers must speed on lake ice, while also controlling the skid of their vehicle (similar in some ways to dirt track racing). The sport has even been modified for ice rinks.
Ice is used to cool and preserve food in iceboxes.
Ice cubes or crushed ice can be used to cool drinks. As the ice melts, it absorbs heat and keeps the drink near 0 °C (32 °F).
Ice can be used as part of an air conditioning system, using battery- or solar-powered fans to blow hot air over the ice. This is especially useful during heat waves when power is out and standard (electrically powered) air conditioners do not work.
Ice can be used (like other cold packs) to reduce swelling (by decreasing blood flow) and pain by pressing it against an area of the body.
Engineers used the substantial strength of pack ice when they constructed Antarctica's first floating ice pier in 1973. Such ice piers are used during cargo operations to load and offload ships. Fleet operations personnel make the floating pier during the winter. They build upon naturally occurring frozen seawater in McMurdo Sound until the dock reaches a depth of about 22 feet (6.7 m). Ice piers have a lifespan of three to five years.
Structures and ice sculptures are built out of large chunks of ice or by spraying water The structures are mostly ornamental (as in the case with ice castles), and not practical for long-term habitation. Ice hotels exist on a seasonal basis in a few cold areas. Igloos are another example of a temporary structure, made primarily from snow.
In cold climates, roads are regularly prepared on iced-over lakes and archipelago areas. Temporarily, even a railroad has been built on ice.
During World War II, Project Habbakuk was an Allied programme which investigated the use of pykrete (wood fibers mixed with ice) as a possible material for warships, especially aircraft carriers, due to the ease with which a vessel immune to torpedoes, and a large deck, could be constructed by ice. A small-scale prototype was built, but the need for such a vessel in the war was removed prior to building it in full-scale.
Ice has even been used as the material for a variety of musical instruments, for example by percussionist Terje Isungset.
The solid phases of several other volatile substances are also referred to as ices; generally a volatile is classed as an ice if its melting point lies above or around 100 K. The best known example is dry ice, the solid form of carbon dioxide.
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Look up ice in Wiktionary, the free dictionary.
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