Blast from the Past: MiniDisc, Wide Bit Stream and 20 Bit

I cannot really tell you, dear reader, why I´m so interested in ancient digital technology. I suspect several reasons but none of them seems clear enough for me. But I know that it seems to be interesting enough for others too - otherwise I couldn´t explain the 3000 monthly pageviews I still find surprising given those geeky topics I usually write about. Today I will not only write about a nerdy subject but also about an example of now ancient technology that quickly became technically obsolete: the MiniDisc. Some months ago I reviewed several portable CD players I had acquired; in that same article I mentionend in passing my first MiniDisc recorder bought in 1996, the Sony MZ-R 30. I also published several measurments I made with this unit and talked about some of the technical features enabling the MiniDisc to function. Ever since that article I had the nagging feeling that I needed to elaborate a bit more on the technical aspects of that system as well as writing about its sound in detail. Well, here it goes.

MiniDisc logotype (copyright: Sony)

The MiniDisc was introduced to the market in 1992, at a time when sales CDs reached an alltime high and the Cassette Tape approached its final evolution with the introduction of Dolby S. By then it already was apparent that the Tape was going to be replaced by CD technology, just the same as Vinyl was. Additionally, Sony and Philips had already developed and standardized the CD-R format in 1989. Back then however the technology needed for CD-R (lasers and media) was alarmingly expensive & still in its infancy so both companies developed something else supposed to be equally capable of digital recording but much less costly. Philips decided on the ill-fated DCC format while Sony decided to use something more cutting edge: MO-discs. They also determined the new format to be much smaller than anything else released before; in order to achieve that they had to use a lossy compression scheme. The result was an MO-disc shrinked to one fifth of its former size combined with a newly developed lossy compression called ATRAC, all of it encapsulated inside a nifty package looking like a tiny floppy disc. This new format appropriately named MiniDisc was - just like DCC - released in 1992 in form of the portable recorder MZ-1. From the minute they presented it I was fascinated by it because it offered some traits completely new to the audio world. Beside being able to record something digitally the MiniDisc was highly portable (remember: we are talking about a time when flash memory was still in its infancy and had yet to be released). But it was the possibility to edit its content to your liking that catapulted the system into the limelight: a user was able to move around or to erase a particular track or several tracks, one could also divide or combine these tracks. In short the perfect personal "Best-of" was now possible - all in flawless digital quality with then unknown portability. Or so Sony thought.

Sony MZ-R 30: have a look at the "Erase" and "Track Mark" buttons - a first back then

Since Philips was going to unleash its DCC system in 1992 Sony had to follow suit in order not to loose marketshare. The engineers of the first MD recorder however knew that they would need at least another year to perfect the compression scheme ATRAC. Have you ever heard the first mp3-encoder from the Fraunhofer Institute? I´m old enough to remember that I did; it sounded just awful. I encoded some track from an Enya album with 128 kBit/s and after decoding it back to .wav I noticed a strange pumping effect and distortions like flanging and pre-echos. Clearly, mp3 wasn´t ready to be used - and the same happened three years prior when the MZ-1 was released. Early tests noticed some strange artifacts sounding like crackling fire on top of sounds in combination with a generally metallic and dull sound; the first version of ATRAC just wasn´t ready for public release. The biggest leap in quality was supposedly achieved with ATRAC 2 one year later: much less metallic, frequency cutoff extended to 18 kHz (before: 15 kHz) and less audible crackling noise. ATRAC 3 from 1995 came close to DAT in a DBT, the crackling noise had almost disappeared. But only ATRAC 3.5, released first in August 1995 with the home component MDS-JA 3 ES would be virtually indistinguishable from CD without metallic sound, noise or anything else. This story serves to illuminate the course of technical improvement being quite visible to the general public. Especially people in Europe were very critical of the new system: the MZ-1 was very expensive, MiniDiscs were equally expensive and all of it sounded just awful. Additionally Sony made an incredibly stupid marketing error: Instead of concentrating on the systems' recording ability they advertised it with pre-recorded MiniDiscs, leading many people to believe that the MD was the CDs successor. Back then people hadn´t yet accepted lossy quality and so they stayed with Tapes a bit longer. In Japan however the MiniDisc was successful from Day One.

Sony MZ-R 30, using the Wide Bit Stream capable ATRAC 4

But all of that changed with the MDS-JA 3 ES. The major reason for improved quality was the decision to switch to quasi-floating point operation within the ATRAC encoder/decoder circuit. Sadly it is an almost publicly unknown fact that virtually every lossy compression scheme (mp3, AAC, OGG) internally works with floating point arithmetic. Integer processing isn´t suited that well for audio since it only can support a limited range of values whereas floating point can represent an almost unlimited amout. The first three ATRAC IC designs processed by using integer values only, limiting their range. When Sony got rid of this restriction ATRAC was ready to work with improved quality, subsequently becoming able of capturing high resolution material. Using their patented "Block Floating Operation" the MiniDisc now was ready to process and store information with higher resolution than CDs 16 Bit. And instead of reducing the bit depth to 16 Bit again during en/decoding Sony just used 20 bit capable A/D-D/A converters in order to make sure that the improved processing depth would be preserved. Meaning: the MDS-JA 3 ES was the first truly 20 bit capable consumer recording device. In 1995 this was a small revolution - not one recorder had been capable of delivering a resolution that high up until that point. Sony therefore took the wise step by advertising it as such while making sure that every internal processing step matched this 20 bit capability, calling the entire process "Wide Bit Stream". On home consumer devices a resolution this high makes perfect sense, it´s an entirely different situation with portable recorders however. Even if a recorder like my MZ-R 30 would work within this bit depth it would be pointless; its combined A/D-D/A converter Asahi Kasei 4515 is a true 16 Bit converter, rendering the internal processing power useless as a result. Likewise, digital 20 Bit sources weren´t existing back then so this impressive processing precision effectively only made sure that CDs were encoded without flaw.

But since the day I first read about it I have been interested in finding out if Sony spoke the truth. Could a lossy device like the MD be capable of delivering higher-than-CD resolution? All those years ago I couldn´t do revealing tests myself only because I lacked the equipment for it. But hey, we now have 2012 and I own the Creative Sound Blaster X-Fi HD USB! As you know it features optical in/outputs delivering true, bit matched 24 Bit signals. My boyfriend also owns a Kenwood DM-5090 (1997) which I suspected to be Wide Bit Stream capable. BTW, despite being advertised featuring an ATRAC 4.5 IC the Kenwood only uses the same ATRAC 4.0 IC from my MZ-R 30. For measuring pure ATRAC performance I devised a  test routine that would protect the digital signal integrity at every step during my procedure without any analogue intersteps. I created an RMAA generated test signal with 24/44.1 and did the following:

SB X-Fi HD ---> Sony MZ-R 30 (recording) ---> Kenwood DM-5090 (playback) ---> SB X-Fi HD

Recording was done digitally using the MZ-R 30

Playback was done digitally with the ATRAC 4.0 equipped Kenwood DM-5090

The results were surprising to say the least. My old MZ-R 30 turned out to be a true Wide Bit Stream capable recorder - only when using digital connections of course. Just imagine you now would find out that a recorder you´ve known for 16 years has been capable of capturing high resolution all the time. For Christ's sake, this thing is from 1996, a time when not even recording studios were using 20 Bit regularly! The Kenwood DM-5090 was equally surprising since its digital output delivers a true 20 Bit signal. A) for a consumer device it would make much more sense to transmit with 16 Bits only and B) my resulting files were actually 20 Bits inside a 24 Bit .wav file (as indicated by the Bit-meter in WaveLab). Look at the results:

Entirely digitally transmitted 16 Bit test signal yields 16 Bit performance using ATRAC

A 24 Bit test signal yields 20 Bit performance thanks to WideBitStream

For comparison: mp3 320 kBit/s CBR (Lame 3.98.4) with 20 Bit output

Sony told the truth indeed: even a small portable MD recorder is capable of recording true 20 Bit quality (Dynamic Range would need to be roughly 10 dB better though). The 16 Bit signal results in 16 Bit quality while the 24 Bit signal yields 20 Bit quality. It would be interesting to measure the output of an ATRAC 4.5 equipped device since that particular ATRAC version was the first to use full 24 Bit processing. Furthermore you now can see how mp3 behaves when it´s properly decoded, allowing it to deliver the full resolution of its internal 32 Bit floating point data (for fairness decreased to 20 Bit in the example above). The mp3 measurment also serves as an example how much lossy codecs have improved during the last 16 years. Granted, results are a bit unfair since ATRAC uses 292 kBit/s whereas the mp3 test signal above was encoded with 320 kBit/s. The most important measurment for all three examples is Total Harmonic Distortion plus Noise (THD + Noise), ATRAC measures 8 dB worse than mp3 which might lead to more audible compression artifacts. But considering its age, its limited processing power and implementation ATRAC fares impressively well. Of course, with every lossy compression scheme only the output with real music counts so measurments might not reveal any sonic shortcomings. For that I not only recorded test signals; I also copied several music examples the same way as described above to find out if ATRAC sounds different to the originals. To determine if there was an audible change was indeed quite difficult, proof to how well Sony designed the whole process. It could very well be a placebo effect but I was under the impression that ATRAC widens & deepens the stage impression very slightly leaving tiny "holes" and a not so stable stage. It also seemed to sound either too harsh or too mellow depending on the material - but keep in mind that the perceived effects were so slight that I´m not sure I´ve even heard them. Impressive, don´t you think?

Sony MZ-R 30

But how does the MZ-R 30 sound? I´ve already talked about this before - but I didn´t rate its sonic quality with my new rating system. The sound of the MZ-R 30 is fairly balanced, blowing up upper bass while missing high frequency detail. Despite this it displays slight loudness-switch characteristics, emphasizing bass and treble frequencies around 10 kHz, efffectively draining sonic colour. Dynamics seem to be held back with the result that the MZ-R 30 always sounds "nice"; bass is soft and misses punch, transients in general are too soft. Staging is fragmented yet flatter and convoluted, guessing size and position of instruments is becoming difficult for the listener. It´s like hearing a fuzzy bubble without much depth and width. What suffers most however is resolution; details are rendered far to casual, more often than not high frequency detail turns into simple noise. High frequency intelligibility really isn´t very well rendered on this device, yielding a voluptuous and too warm sound. Don´t get me wrong, it sounds moderately well, definitely better than 40% of my portable players. Without colouring the sound too much it presents music very pleasant, you can therefore listen with it for extended periods without suffering from listening fatigue. Its headphone output on the other hand - although powerful enough - sucks big time. Using it one looses much crispness, it sounds surprisingly dull.

Sonic Balance:

Dynamics:

Resolution:

Stage / Ambiance:

Character:

A personal Note

Of course it´s pointless to use such an ancient device in present times. Recent portable players can be filled with music in a matter of seconds, offer theoretically improved sound quality (using lossless FLAC and improved technology) and are much smaller in size while offering reasonable running times. With musical gadgets convenience always is key while quality plays a secondary role. Therefore technological obsolescence plays a major role in the death of the MiniDisc. 

But there are other reasons as well... up above I´ve talked about CD-R - since they were so expensive Sony estimated it would take a long time for them to become affordable. They were wrong: recordable CDs became cheaper than MDs in 2000/2001, rendering the MiniDisc an inconvenient and slow recording device with a compromising quality approach. The mighty giant Sony reacted with altering the MD format by introducing an advanced version of ATRAC called ATRAC3 (not to be confused with ATRAC 3) which allowed longer recording times by lowering the datarate (64 kBit/s & 132 kBit/s). Needless to say that such recordings were incompatible with older MD devices. 

Around the same time a second problem arose: portable mp3 players. Sony tried to counter these developments with another new feature released in 2002 called NetMD where you could - using your PC - upload your music to a recorder equipped as such via a built-in USB link. Of course, you had to use the proprietary ATRAC compression scheme, meaning that you had to re-encode your collection of mp3-files, lowering the quality even further (lossy re-encoded to lossy). For all consumers it was as clear as day that this was highly inconvenient and extremely impractical - but Sony found nothing by it. Subsequently many consumers parted with Sony and the MiniDisc. 

Kenwood DM-5090 - an MD recorder from the systems' heydays - and not even from Sony

The last nail into the coffin of MiniDisc however was the release of the iPod in 2001 and its subsequent success. Again Sony completely misinterpreted unfolding developments and tried to revive the almost deceased MiniDisc corpse by improving the recording quality. They introduced the Hi-MD in 2004 - for the first time in its life the MiniDisc was able to record and playback music in true lossless 16/44.1 quality, all of that combined with NetMD "comfort". Yes, they dropped the Wide Bit Stream feature entirely. It´s ironic: to infuse the system with new life they not only sacrificed something that made the MiniDisc unique (admittedly: many people didn´t care) but also compromised backwards compatibility. Sony subsequently lost its "coolness", the MiniDisc was just one of many decisions made in the first years of the new millenium that stank of stupidity. The once shining company that produced legendary components now is just a mere shadow of its former self, making more profit with finances (!). Remember: Sony is at heart a manufacturer of electronics and not a bank. Today Apple is hip while Samsung is market leader, both traits were personified by one company just ten years ago: Sony.

Sony may die a slow death - but thankfully their components are still around and obviously built to last for quite some time. I for one have decided to go back to the MiniDisc system for now, even though production has ceased in 2011 and I myself abandoned it in 2001. Why am I so stupid and unreasonable? I don´t really know... but the first time I touched the Sony MZ-R 30 I knew that I was in love. This never happened when I received my Sansa Clip+, it was just another device playing music. Furthermore I never trusted mp3 - without a logical reason really. By now lossy codecs have reached a mindboggling quality, with higher data rates they in fact are transparent. Still, to me mp3 always sounded a bit dull and compact. I know, I know... completely stupid and very likely a placebo. But I can´t help myself, I always perceived the MiniDisc to sound better. It also looks and feels very nice, it has a haptic mp3 cannot reach since it´s immaterial. Some weeks ago I read an essay in the German news magazine Der Spiegel called "You cannot love files". This article described how soulless downloaded music appears to many customers´and it argued that today you can buy music in a second and have it on your portable player the next. But you cannot hold it in your hand (like a CD , MD or even Vinyl), leading to a feeling of being disconnected from it. You don´t have to occupy yourself with it anymore, it´s just data confined within impersonal files. I´ve always wondered why I "remaster" every CD I buy (which are many), maybe it´s because I want to "connect" with it before it ends up in pristine quality on my HDD where it´ll only be a collection of files. My recent interest in vintage portable players or the MiniDisc forces me to do the same, I have to bother myself with the music, I have to spend time with it. In any case I have not understood the reasons for this yet, I´m just starting. Maybe it´s much simpler and I´m starting to get old. Equally possible but you know what? I don´t care because I want to enjoy music in very good sound - and the MiniDisc allows me to do that despite (or because?) its shortcomings.

More USB cables - more differences

Please go ahead and read the first and the third and last article about USB cables - especially the last one is important.

Just like I´m looking above with a lot hairy sausages on my head from the lovely movie "Kismet" I also feel like that inside my head: twisted and taut. The sausages I refer to are obviously more USB cables. My last test revealed measurable differences between two USB cables with similary striking audible results - at least in my opinion. Furthermore I wondered how other USB cables would measure but I couldn´t do test with my other cables because the SoundBlaster X-Fi USB HD required a cable with a Micro USB plug. And yesterday another thing happened: the wonderful Vincent Kars from thewelltemperedcomputer referred to my tests not only on his website (thanks again, Vincent) but also on the Whatsbestforum. One member there made me think about effects related to the power supply and that different cables perhaps would supply power better then others so I was curious since 1. I changed my USB connections since the last test and 2. today I bought an adapter so that every cable can be used now with the SoundBlaster.

I said that I changed the configuration of my USB connections. What I meant by that is that I bought a USB bracket - I wanted to use an additional internal USB hub that has been laying dormant since I got my PC in 2010. Why? Because on my first test the SoundBlaster was connected to one particular internal hub that shared its port with several other devices: a USB flash drive for ReadyBoost, my printer, my external USB DVD drive and my keyboard. Thanks to the new USB bracket there is just one other device beside the SoundBlaster connected to this internal hub now: my DVD drive (which is self-powered). All other devices now either use the new bracket (and by that the previously dormant internal hub) or the third internal hub that has been present before but wasn´t used (stupid me). Oh, before I forget: when I´m talking about internal USB Hubs I´m referring to the ones already built onto the mainboard - not to some external hub that can be bought everywhere. Every PC has a built-in USB controller, to that several internal hubs are connected and these hubs extend to the USB-ports you can see at the back or at the front. In my case I now use four seperate internal hubs. But on to the cables, shall we?

From left to right: NuForce Impulse, Monster USB, a cheap Belkin,
Oehlbach USB and the Audioquest

All cables are relatively inexpensive and all cables - the Belkin being the exception - have the audiophile crowd in mind. The NuForce Impulse was reviewed in the german audio magazine "Audio" some months ago and subsequently was awared their BestBuy. The Monster Cable has been in my possession since 2005 and is the most expensive cable (I paid roughly 60,- Euros but it has dropped in price considerably since then) and it is not even USB 2.0 certified. The Belkin is a cable I bought for the cheapest money possible and it has been used with my scanner only after testing it. The Oehlbach was bought in 2010 for connecting my E-MU but for quite some time now it has been used with my external DVD drive, the E-MU now is connected to the NuForce. The Oehlbach, the Audioquest and the NuForce each cost around 30,- Euros. Despite its price the Monster started to disintegrate a few years ago (the mesh that covers the cable has become very brittle) but it still functions well. For this test I also ignored the cable that came with my SoundBlaster since I was more interested in how these other cables would compare to the Audioquest. Secondly I have not been doing any listening tests with these cables. But I can tell you that I´ve thouroughly reviewed them for myself over the years with my E-MU: the NuForce "sounds" the best, very far away is the Oehlbach that "sounds" relatively similar to the standard cable (only slightly more precision), then comes the Monster that adds too much bass and shows wrong timing while the Belkin sits firmly on the last place by being the worst cable of them all (worse then the standard cable).

NuForce Impulse

Monster USB

Belkin USB

Oehlbach USB

Audioquest Forest USB

An alert reader will by now have discovered that the measurments for the Audioquest have changed since my last test: the noise levels have been improved considerably. This is very interesting since the SoundBlaster is still connected to the same USB port - but I also disconnected three other devices from the same internal hub. Since the other devices are now missing the Audioquest fares visibly better which could mean that USB interfaces in general are susceptible to other devices connected to the same internal hub, an effect possibly amplified by more expensive boutique cables. BTW, the test conditions have not been changed (apart from the disconnected USB devices) since the last test. The recording device still is the ASUS Xonar Essence ST, the levels are the same as are the used driver interfaces and the Windows configuration. So, by looking at those charts you´d think that nothing interesting has happened, right? Because with the exception of the Belkin all cables appear to measure more or less the same, the small differences can be ignored because of a possible error margin coming from the used soundcards (although I again repeated these tests five times each and the results were always consistent (differences were +/- 0.2 dB at max)) - or can they not?  
And because it´s so important for you to understand what I´m really doing here I´ll repeat these sentences again: when I talk about "measurments" you cannot take that literally! From a scientific standpoint my results are nothing more then nice looking pictures. I don´t know how RMAA "measures" but the pictures you can see most likely are several separate results taken over an unspecified period of time that have been middled or averaged for the picture (in essence, the pictures are all graphs). For showing a real difference I would have to take my five "measurments" of one cable, average them, then take the other cable to do the same. Finally I would have to do a statistically valid comparison or calculation between those two averages to express the differences in percentages. But since I´m not a scientist and since I´m a jerk with statistics I won´t be (cannot) doing this, I´m just Marlene D. and I like to play around a lot.

Noisefloor NuForce Impulse

Noisefloor Monster USB

Noisefloor Belkin USB

Noisefloor Oehlbach USB

Noisefloor Audioquest Forest

As you can see the RMAA charts above don´t show everything. RMAA also misinterprets noise as distortions, I´ll show that during the next pictures. The plots however reveal that the Audioquest still shows roughly the same noisefloor response just like last time: deep frequency noise is visibly higher when compared to the other cables even though the overall noisefloor has been decreased. The NuForce and the Monster show the same noisefloor while the Oehlbach is a mixture of those two and the Audioquest. The Belkin however is another case: high frequency noise has been increased roughly 10 dB. Now to the THD (Total Harmonic Distortions) measurments:

THD NuForce Impulse

THD Monster USB

THD Belkin USB

THD Oehlbach USB

THD Audioquest Forest

There we have it again: the Belkin cable shows the highest high frequency noise whereas all other cables behave quite normal - the Belkin also shows the highest distortions. The Audioquest again shows more low frequency noise but distortions of the Audioquest/Soundblaster combination are slightly lower (especially the peak at 2.000 Hz). I´m at a loss here, dear reader, because I don´t know what that means. Perhaps the more expensive cables deliver power from the USB port a bit "better" in a way that shows faults of the PC power supply. Or they submit errors produced by other connected devices better or worse (maybe the standard cable has something built-in that rejects those errors). Anyhow, one thing is for sure: when you connect a USB sound interface to your computer you should make sure that - if possible - no other device is connected to the same internal hub (you can have a look at the usage of the internal hubs with the Device Manager in Windows) because it appears that the more expensive boutique cables reveal USB errors or shortcomings of currently unknown kind different then standard cables. Phew, now I´m going to have a smoke, a coffee and a piece of sweet cake... ;)

Last update: 09.01.2013

Creative Labs Soundblaster X-Fi HD USB / Digital Music Premium HD - is it any good? - A review

Please note that the following review is a major rewrite of the original article where I ended up recommending this soundcard. I cannot do so anymore - to find out why you have to read it again. There´s an alternative for the X-Fi HD USB: the FiiO E07K 'Andes'. It doesn´t feature an RIAA amp and cannot record - but it´s equipped with true 44.1 kHz playback and it sounds just perfect with headphones from 16-150 Ohm.

Since originally posting this article on January 6, 2012 exactly one year has passed and in the meantime I haven´t been inactive when it comes to research concerning the X-Fi HD USB / Digital Music Premium HD. Why would I alter an already written article siginificantly? You know, bloggers consider this to be bad form because it´s not exactly an example of transparency. Secondly it´s unfair to people who might´ve bought this card because of myself recommending it. Point is, during the year that has passed I´ve accumulated some additional information and experience I cannot ignore which will lead me to alter my conclusion considerably. My original conclusion was like this: "...especially for this price - this is a well designed and very good sounding interface with a lot of available connections and features (...) Recording quality is good, playback quality even better, the headphone output is strong enough for most available headphones with impedances from 16-150 Ohms on every system, build quality is well done, design is nice... I cannot wish to have more for the money. Guys, this thing is ridiculously cheap considering its price, it´s a true bargain. I never liked my X-Fi eXtreme Music... but oh, I love this one!" In the end of this now rewritten review you will bear witness to a changed opinion of mine. Yes, I´m ashamed to admit that I seem to have been wrong about many things with this card - I could have gone the easy route and kept my mouth shut. Instead I wanted to be as honest with you as I can be, I would not be able to forgive myself for keeping the truth from you. BTW, this occasion also provided the opportunity to make new and hopefully improved photos. YAY!!

Creative Labs Soundblaster X-Fi HD USB / Digital Music Premium HD

I acquired this little inexpensive gadget only because I´d found out with my then new Sennheiser HD-448 that the headphone output of my Lenovo SL-510 sucks. While this wasn´t obvious with my Superlux it became irritating soon with the very balanced Sennheiser because of missing treble and flat stageing. In the end I decided to buy another soundcard which turned out to be the X-Fi HD USB. True, I could have used my E-MU 0202 USB instead but its headphone output has a high output impedance (22 Ohms) and is pretty weak. Since the new Soundblaster was intended to be used soleley at our second appartement with one of my headphones it was of vital importance for it to contain a strong enough headphone output with low output impedance. For amplifying headphones the card uses the 4556 op-amp by JRC, this amp has been on the market for almost 30 years and it´s still a decent thing considering its price because it has a low output impedance (of just 1 Ohm) in combination with low distortions... that is if it´s treated right. For communication via USB the external card uses the CA0189 from Creative, the high quality D/A-converter is an AK4396VF from Asahi-Kasei while the CS5351 from Cirrus-Logic is responsible for A/D-conversion. But this card has something that distinguishes it from many other USB interfaces: it contains an RIAA amp, enabling you to connect your turntable to this interface directly without the need of an additional pre-amp. I thought that this particular feature might come in handy should I have the desire to capture vinyl. As it turned out during the last year I have not captured one single LP yet (except for testing); it probably has something to do with my strong dislike for this obnoxious and dreaded medium. Well, it doesn´t matter since this feature will not disappear suddenly, won´t it? To my own surprise I have instead used another aspect of this card quite extensively: its digital optical output made it possible to record music onto MiniDisc in high quality.

The inside of the Sound Blaster X-Fi HD USB. Not "audiophile" but high quality.

Copyright by Creative Labs.

I assume that you might have some reservations towards Creative cards; I´m aware that many people experienced problems with them - I myself never did though, every Creative card I´ve owned has been behaving as it should. Manufacturing quality and finish are decent considering the used materials (plastic). It posesses gold-plated connectors (it´s pointless for audio quality; it only avoids corrosion) and its outer shell feels nice to the touch. I especially love how smooth the volume button turns. But it´s very light and that could create problems: imagine plugging in a headphone - the card will simply slip if you don´t hold it in your hand. Setting up the card was easy, installing and upgrading didn´t produce any errors no matter where and on which PC I did it. BTW, I chose not to install the bloated software suite Creative offers, I picked the driver and the audio panel only. Fans of the DSPs typical for Creative (EAX 4.0, THX Studio Pro Crystalizer, Surround etc.) will be happy 'cause the card is equipped with them. Nonetheless they should be aware that all DSP functions are done in software and not in hardware like on the internal X-Fi cards which creates additional computing stress for an older PC or one of those low-power PCs. If you´re willing to experiment a bit, if you want to avoid installing issues or if you´d like to have the newest drivers (Creative is a bit lazy there) I can recommend a fully updated package conceived by the famous Daniel K.; get it here. The DSPs also provide an indication who the target audience for this card is: your average Joe with an interest in good sound quality for every day tasks or gaming, a lot of features and some toys to play around with. Music Professionals? This card lacks routing options, ASIO inputs for multitrack recording or XLR ports so it isn´t suited for professional music production. On the whole it feels like a small gadget able to be connected to your stereo system - that´s actually OK, Creative doesn´t hide this. Several people all around the web have reported that this card can be used as a DAC - I haven´t used it that way yet. Furthermore it still needs a running PC (in order to be powered). Well, it´s nice to have that feature.

Creative Labs Soundblaster X-Fi HD USB front

So far I´ve talked about its relative advantages and the features it offers. What about shortcomings, are there any? Indeed there are! Creative claims that this card offers an audiophile headphone amp. To determine if the JRC 4556 really is of audiophile quality we first have to make clear what the expression 'audiophile' actually means. If it means using anything out of the ordinary then this card isn´t audiophile because it uses readily available, not too costly parts. But as I´ve shown this isn´t an issue because something extremely well sounding can be produced using cheap and simple parts only. Should 'audiophile' mean engineering prowess, then the answer would be Yes/No. Recording and especially playback quality is very decent - but only if you use the line-in / line-out. The headphone output on the other hand seems to be a good example of botched engineering: Creative managed to turn a decent part with perfectly low output impedance into something with an output impedance too high for many headphones the card is actually suited for considering available voltage levels provided by the USB connection. The PCI-Express counterpart for this card, the Titanium HD, uses the same JRC 4556 IC and on that card it has a reported output impedance of 36 Ohms - way too much for IEMs, my HD-448 or my Superlux. I have to make it clear that this isn´t the fault of the IC itself; Creative seems to have added parts to save on engineering and it shows. To find out why that could create problems look at an example from an ancient portable player below:

Sony MZ-R 55 - headphone out with Triple.Fi 10 (copyright not with me)

The frequency reading of this exemplary unit above should ideally be a straight line - instead the high impedance of the MZ-R 55 headphone output creates severe frequency deviations with IEMs which WILL be audible. Since the PCB circuitry for the headphone amplifier looks similar on both Creative cards (according to others) we can safely assume that both will behave in a similar way, meaning that the X-Fi HD USB would have an equally high headphone output impedance creating the same or even stronger deviations like the ones pictured above. Yes, you´d have to say "Bye bye" to balanced sound quality. So in essence with the X-Fi HD USB you´ll have lovely audio quality using its line-out - but the headphone output will produce sonic crap should you be using it with low impedance cans susceptible to high impedance outputs. As a basic rule the headphone impedance should be 8 times higher than the output impedance of the amplifier the headphone is connected to. For the X-Fi HD USB you therefore would need a headphone with an impedance of at least 288 Ohms in order to reach balanced sound. Enter my Sennheiser HD-600 which boasts 300 Ohms... but wait, why is this gorgeous headphone so soft in volume? Because the X-Fi HD USB doesn´t offer enough power for such a demanding and power hungry creature (even though Creative advertises it that way). Which means that for the Creative Labs Soundblaster X-Fi HD USB you´d need a seperate headphone amp to unleash its full potential. Kind of defeats the purpose, don´t you think?

X-Fi HD USB headphone output and microphone input

The disadvantages don´t stop with the dreaded headphone out. Are you planning to play 44.1 / 88.2 kHz material with this card NOT using any resampling? Forget it then. The analogue in-/outputs only offer 48 / 96 kHz sampling rates. This card lacks a seperate crystal needed for 44.1 kHz-based samplerates even though the CA0189 used for USB communication is actually able to handle one of them (44.1). Which creates the second problem: the optical S/PDIF connectors can only process 44.1, 48 & 96 kHz - but they ignore 88.2. Why does all of this pose a problem? Because the good old CD uses a samplerate of 44.1 kHz, a standard the X-Fi HD USB cannot handle with its analogue outputs and inputs. Therefore a CD will always be resampled to 48 kHz or to 96 kHz (depending on what is configured in the Windows WASAPI control panel). Using 88.2 kHz files from for example HDTracks.com with the digital output of this Creative is not possible, at least not without resampling. Digital recording of 88.2 kHz material with its digital input? Don´t even think about it, the card won´t recognize it (I´ve tried). This 'fine' example of engineering seems to have been constructed 15 years ago when those samplerates indeed weren´t very common on PCs. Is this audiophile? I think you can now answer this question yourself.

Backside of the X-Fi HD USB

But now to measurments with RMAA. The first measurment I did for the original review was the commonly employed loopback from the output to the input of the same card via an RCA cable. Many computer magazines do this kind of measurment although it´s unsuitable for finding out if a soundcard behaves well. Using a loopback you for instance don´t know if it´s the output that´s noisy or the input because noise or distortions exhibited by the output are masking the possibly noise- or distortionfree input or vice versa. Therefore I´ve removed it for this updated article. Much more precise than the loopback are seperate testruns done seperately for the line-in and the line-out. So I connected the output of the Soundblaster to the input of the ASUS Xonar Essence ST and the other way round, both times using the same RCA cable. While a PC is inadequate for measuring a soundcard because of grounding issues I knew for certain that my ASUS behaves exceptionally well on it´s in/outputs (noise level of -115 dB for the output and -114 dB for the input, no distortions or jitter). To make it short I was fairly positive that it would be good enough for the purpose of exposing possible flaws of the X-Fi HD USB.

Recording (line in, 50 %): from ASUS to Soundblaster X-Fi HD, one year later,
using two different PCs, one on batteries

Playback (line out, 0 dB fs): from Soundblaster X-Fi HD to ASUS, one year later, 
using two different PCs, one on batteries - spectacular results

My latest article about USB cables made it clear that the playback part of this soundcard is perfectly engineered. During the tests for that article it transpired that I indeed had been measuring the effect of a ground loop a year ago. The result was that the old measurments did not show the possible performance of the Creative so I replaced them with the ones I did for the third article about USB cables. To the measurments: the DAC AK4396V is rated at having a noisefloor of -114 dB (min.) - Creative manages the feet of achieving fantastic -113 dB. Every measurment was done in 24/96 using 0 dB fs for both cards - except on the input of the Sound Blaster: its volume slider produced a perfect 0 dB fs input signal only at 50 % of the available recording level. Setting a recording level of 100 % I experienced severe distortions from an overloading input. That behaviour is caused by the line-in also used as an input for vinyl - the amplifier inside this card is always active. With vinyl records there also is a very noticeable gain of frequencies from 7.000 to 12.000 kHz, beyond those frequencies the band decreases sharply. This indicates capacity problems of the input when receiving vinyl signals but it isn´t a serious issue since 85% of commonly available RIAA amps behave exactly like that. Another thing: either the same line-in/vinyl amplifier of this card is used for the microphone input on the front - or a (possible) seperate microphone amplifier produces noise leaking into the line-in. The latter would demonstrate engineering errors:

Noise, line-in

The left channel is noisier on lower frequencies than the right channel; I assume the left stereo channel of the line-in probably doubles as the monaural microphone input. This is complaining on a high level because this noisefloor is OK for such a low-priced soundinterface. However, a few months ago I´ve stumbled upon an additional row of measurments on another site which revealed strong distortions. Since the loopback method was used I can´t tell if the input or the output distorts, I can only say that I myself haven´t witnessed distortions using the same method. EDIT 05.08.13: Hmm, that blog is now gone. My seperate testruns for recording and playback revealed that they are indeed higher for the input than for the output but non-threatening at all. My unit is practically distortion free though two different units of the same card measuring differently using a loopback might suggest poor quality control on Creatives' side, changed specs or measurments done wrong (happened to me too). Another typical flaw of cheap USB soundcards are high levels of jitter. Not with this card as you can see on the two pictures below:

Jitter, line-in, 24/96

Jitter, line-out, 24/96

The performance is excellent, playback as well as recording are virtually free of jitter. Because I was using a samplerate of 96 kHz for the Creative and 192 kHz for the ASUS I have effectively measured the jitter performance for both cards combined - even more impressive, isn´t it? It wasn´t that surprising since this soundcard employs the asynchronous USB transfer: instead of the PC pushing the data towards it the interface itself demands the data only when needed, it therefore is in complete control of the connection and its data transfer. On earlier USB interfaces the theoretically inferior synchronous or adaptive modes were used, occasionally prompting high jitter levels. I should however mention that asynchronous USB doesn´t automatically guarantees perfect audio, the engineers still need to be skilled to avoid jitter. Are you curious to find out for yourself which USB mode your own USB soundcard uses? In that case I can recommend the USB Decriptor Dumper from Thesycon.

X-Fi HD from above

Before I´ll tell you about audio quality I have to mention that I´ve used the X-Fi HD only in combination with the Audioquest Forest USB cable during the last year. I have written three articles about this and other (supposedly) High End cables: "Hot Vodoo: Audio differences between USB cables - yes, they do exist!" and "More USB cables - more differences", articles that proved to be highly controversial. The third and last article about USB cables "Vodoo continued: my final Statement on USB cables" mainly deals with the effects of a ground loop I have been measuring in the older articles. Also, please note that I´m able to apply my testing methodology only to the line-out but not the headphone output. It goes without saying that I did every single test not using any of the DSPs the card offers.

Sound with the line-out: The sound of this card is very good for playback. Compared to the reference files the Soundblaster X-Fi HD USB lacks a bit of high frequency gloss or 'air' which diminishes resolution and detail a bit. Bass is stronger than my reference files, that difference is small but noticeable. Speed and snap are marvellous over the whole frequency band, music indeed seem a bit 'faster'. Overall, the dynamics are exaggerated; they aren´t completely natural but riveting nonetheless, more importantly they never veer into strident territory. The stage is fascinating too: while it isn´t as wide as the reference it showcases more depth augmenting holographic impression. I found it very pleasing that the X-Fi HD USB borrows some of its characteristics from the excellent Sony D-335. The character of the original files is not retained completely, it´s partly replaced by something with a more forward sound. To put it bluntly: music is more fun coming from this card. In conclusion the line-out is not 100 % sonically invisible but for casual listening (or for almost anyone of its users) it´s perfectly suited. Yes, I think that many people will just love the sound the Creative creates (pun intended). Should you be using the stock USB cable the card was equipped with you will however encounter a flatter stage, its already exaggerated dynamic capabilities will turn from engaging to strident. You decide. Here are now my ratings for the line-out (Audioquest Forest used):

Sonic Balance:

Dynamics:

Resolution:

Stage / Ambiance:

Character:

Recording quality: the frequency deviation with vinyl signals is noticeable, causing hoarse sounding singers and too much 'air'. It´s also responsible for something best described as a brittle sound my two other RIAA amplifiers - which aren´t very good - lack. On the other hand playback of vinyl is not an exact science because of too many factors producing unreliable results. I can only say that for me the quality is good enough (I´d correct errors anyway). Recording usual line-in signals produces a slightly constricted sound, missing resolution and less dynamics. While this doesn´t sound it isn´t because the overall recording quality is decent. The noise signature of the left channel  revealed in my measurments above wasn´t audible.

Sound quality of the headphone output: Despite a way too high output impedance I have yet to encounter imbalanced sound quality with this card using headphones. I seem to have been lucky because my Sennheiser HD-448 and my Superlux HD-668B don´t have any problems with high output impedances, according to measurments on headphone.com they virtually aren´t susceptible to them. Compared to my FiiO E6 this card amplifies lower frequencies, creating more bass power as a result (without sounding bloated). Secondly, it presents music with more dynamics than it really has, making it a bit more aggressive and by that mirroring the sound of the the line-out. Can high impedance headphones like the Sennheiser HD-600 be used with it? Not the best idea, the card doesn´t have enough power for power hungry cans like these, the volume that can be reached might be too soft for some. Using the HD-600 in combination with the maximum volume setting creates distortions on transients; the headphone output cannot deliver what my HD-600 'demands'. Using it with a volume setting slightly below the maximum (90-95 %) these distortions are almost absent, yet the music lacks a bit 'body', meaning soloists have less chest. In short this combination sounds a bit thinner and slightly strident. I have not used IEMs or headphones sensitive to high output impedances with this card and I don´t intend to do so - in such cases I recommend to stay away from this card as far as possible.

Both the HD-448/449 & the HD-668B virtually aren´t susceptible to high output impdances

Concluding my revised article I can only say that the X-Fi HD USB is a mixture of good and bad. Creative claims that this soundcard is for audiophiles. Experience and research however reveal that this claim merely is wishful thinking of Creatives' marketing division and not grounded in reality. Simply put: the headphone output is crap. I´m sorry to say it as blunt as this, even when I consider that I haven´t had any problems at all. But I use headphones not affected by the high output impedance so I´m forced to ignore my own experience in this case. My point is that you, dear reader, probably don´t know if your headphones react to something like this; with this card you might think that the new and nifty cans you just bought don´t sound very well when in reality it is caused by a mismatch between the X-Fi HD USB and your headphone. You plan on using headphones with impedances higher than 250 Ohms to avoid this problem? Congratulations, you´ve just hit another obstacle because this card is too weak to power them sufficiently. Oh, you intend to play CDs in perfect quality with it? I´m sorry but this isn´t possible either because the lack of support for 44.1 kHz based samplerates forces the Windows audio engine to resample using its not very sophisticated interal resampler. You want to play the newest 88.2 kHz remaster of an ancient Rolling Stones album you just bought on HDTracks to feed it digitally to your very well engineered DAC? I´m very sorry, this is impossible too: Windows resampling kicks in again. 
This card is only for you if you can accept a loss in quality - or if you´re using 48 / 96 kHz exclusively, don´t use headphones vulnerable to high output impedance or weak output power and if you plan on correcting frequency errors produced by the RIAA amp needed for vinyl yourself with a high quality EQ. Should you find yourself in the latter description you will get decent manufacturing quality combined with a nifty looking exterior, very decent audio quality on the line-out and tons of DSPs to play with. One thing however is crystal clear: think carefully to which of the two groups you belong for this card is a disappointment in some regards. It took me a year to find out how badly this soundcard performs regarding certain aspects; I subsequently made the decision that this will be my final Creative product. For listening with headphones I can recommend the FiiO E07K 'Andes' warmly, it cannot record, nor does it feature digital in- and outputs, yet it´s impeccably neutral and able to power low impedance headphones competently.

Latest update: 11.01.2013