I’m sure you’ll be pleased to hear that sound cards have started getting interesting again after years of a boring one horse race. It wasn’t too long ago when we looked at the Asus Xonar D2X – the PCI-Express x1 version of the original D2. Both of which were great cards with tons of features, but they were pretty expensive and excessively so for many. They were also lacking the key gaming feature—Environmental Audio Extensions (EAX)—which prevented some of our readers from swapping their Creative X-Fi out for a Xonar. It became a case that it was X-Fi for gaming, Xonar for music and movies.

　　Since then the tables have not only been turned, they’ve been picked up and viciously shaken by the legs. This follows on from recent events where Creative managed to annoy just about everyone in the enthusiast community because of the way it treated Daniel K, which many users felt was unacceptable considering Creative’s attitude to its own driver development and feature support.

　　In an almost perfectly timed kick when the competition was down, Asus announced that it had reverse engineered EAX Advanced HD by releasing a free update to its XP and Vista drivers for DS3D (Direct Sound 3D) GX engine; this upgraded it to “version 2.0”. Overnight this effectively seemed to remove any reason to buy a Creative soundcard.

　　Naturally Creative didn’t see it this way, and said that you only get the true experience from a proper X-Fi card. While this may be true, we bet the combination of both events has compounded a movement from Creative to Asus.

　　Even then, we still begged Asus for something a bit cheaper than the £100 Xonar D2 and D2X – at the time of review, the Creative X-Fi XtremeGamer was a solid card at a great price, but it was effectively unchallenged in the market. We weren’t asking for something completely “no frills” from Asus, just a product that produced great sound without the weight of a million Dolby and DTS extensions.

　　Finally, it seems our mad hollering has been answered as Asus has launched its Xonar DX – a half height card that comes in at about half the price of the original D2 and D2X, but still retains the high quality hardware, a few Dolby features and the new PCI-Express x1 interface. It's a year later than the XtremeGamer, but is it just that much better? We find out.

Feature List

• Audio Processor: ASUS AV100
• PCI-Express x1
• Max Channels Supported: 7.1
• Max Sampling Rate: 24-bit/192kHz
• EAX level: "5"
• Dolby Home Theatre Technologies
• ASIO 2.0
• ALT (Analogue Loopback Transformation) Technology
• Front Panel audio header
• SNR: 116dB front, 112dB side, centre and rear
• Analogue 3.5mm audio jacks and optical S/PDIF

Box Contents

　　Unlike the full fat Xonar, the DX has a fairly minimal package, although there’s still more in the box than what came with the XtremeGamer when we looked at that. With the Xonar DX, Asus includes a manual, a driver CD, an S/PDIF optical out adapter and a half height PCI bracket. That’s pretty funky – it’s never a guarantee to get a half height bracket with a half height card, so this should be useful if you’re planning a low profile system for a home theatre PC for example.

　　Asus has changed the hardware on the DX slightly, instead of the AV200 chipset on the D2X we now have the AV100 – it’s still the same CMedia Oxygen HD chipset we first saw way back in 2006 on the Sondigo Inferno 7.1, which makes it the same chipset as the AV200. The difference is that Asus hand picks the best chips and labels them AV200 to ensure better quality.

　　The Digital to Analogue converters are no longer the 123dB SNR Burr Brown made by Texas Instruments, instead the task is split between two Cirrus Logic chipsets: the CS4398 (front) and the CS4362A (centre, side and rear). This is because the front channels have a (quoted) SNR of 116dB and the rest are 112dB – in comparison the D2X had 118dB all round.

　　This is still significantly more than on-board audio can muster as it often struggles to scratch at 90dB for even the best chipsets and most expensive boards. In comparison, Creative uses a single Cirrus Logic chipset, the CS4382, which supplies all channels with 114dB SNR on its XtremeGamer.

　　What’s interesting is that while we always take SNR “rated values” with a pinch of salt, these seem more accurate than usual. Digging out the specification for these parts, Cirrus Logic rates these as 118dB and 114dB respectively, so it looks like Asus’s use in the Xonar DX is just 2dB less than perfect.

　　So, if you’re a heavily into your surround sound then Creative might be fractionally better—at least on paper—but if headphones or a set of Stereo speakers suit your desktop better, then the Asus is probably the favoured choice. In reality though there will be no noticeable difference unless you’ve the most acute sense of hearing – something some of us might claim, but few of us music lovers actually have after years of abuse from Walkmans, iPods, night clubs, gigs and concerts.

　　If anything Asus’s approach is clever – while 7.1 or even 5.1 audio would be nice, we’d argue that few have the space for it around a PC desk and most of us opt for stereo (with sub) and/or headphones, therefore quality weighting the front two channels makes perfect sense.

　　In terms of analogue recording, the Asus is better kitted with its Cirrus Logic CS5361 which supports a higher frequency range of up to 24-bit/192KHz and a better SNR of 112dB compared to the XtremeGamer’s Wolfson Electronics WM8775 which is only 24-bit/96KHz at 102dB SNR.

　　Chipset pedants aside, the general package that Asus uses is simply better in every respect – the card uses an updated PCI-Express x1 interface and it specifically uses not only solid aluminium capped capacitors, but also low ESR surface mount ones. Gigabyte also uses this type of caps on some of its premium DQ6 motherboards because they are particularly niche. They induce less interference in the PCB compared to traditional DIP capacitors that the XtremeGamer uses.

　　Like the D2 and D2X, the Xonar DX still requires a power connector and while we never got an answer as to why this was the case when we first did our D2X review, we have since had chance to sit down with a couple of engineers working on the Xonar project.

　　When asked, they explained that this is purely because the power from a PSU is far cleaner than it is from the motherboard, meaning you again get far less interference and therefore better quality sound. At least, that’s how the theory works.

　　Sure, it’s a pain in the back side, especially since it’s a floppy connector and not a Molex, but we have more respect for it now that we know its presence is actually for our benefit.

　　The connector setup is also better than the XtremeGamer – Asus uses a standard four stereo 3.5mm audio jacks for the 7.1 surround sound, and the fifth jack doubles as optical S/PDIF out and microphone/line in.

　　This should work with any set of speakers you buy. In contrast, if you want to use a 7.1 surround setup with the Creative card you have to find a compatible set of speakers that use four-pole 3.5mm plugs, not the usual three pole which is at best, a ball ache.

　　Missing from the Xonar DX are the LED backlit sockets – so instead of being able to easily tell which plug needs to go where you’re left in the dark because while the sockets are labelled, they aren’t colour coded like they are on the XtremeGamer. It's simply a style over ease of use issue, that's all – you can't win with both here. If we weren’t such cool, cutting edge fashion gurus we’d probably not even care that the Asus Xonar DX even looks better – its gunmetal PCI bracket and gold plated audio connectors fit perfectly with the brown PCB.

Shoehorning in EAX 5.0　　Before now, EAX 2.0 was the only Creative EAX that could be used by other companies but this is an old technology though, limiting the user to just 32 simultaneous 3D voices. All the EAX Advanced HD versions from 3.0 to 5.0 had been limited to Creative hardware itself from the Audigy onwards – in comparison, version 5.0 supports up to 128 simultaneous 3D voices and the “Advanced HD” aspect also means it allows for higher frequencies and sampling rates.

　　What Asus has done is reverse engineer its new DS3D GX 2.0 engine to emulate EAX 5.0 support (which is merely an extension of 3.0 and 4.0). The Xonar now supports the same 128 voices and HD frequencies and sampling rates to match the Creative, although the processing is done through software on the host CPU not the card itself. When the X-Fi launched in 2005, multi-core CPUs were few and far between, so offloading sound processing from the single CPU core was a good idea at the time, however we’re now in a time where dual and quad-cores are the norm.

　　At the same time, games are still largely single threaded or marginally threaded, allowing some spare overhead to be used for audio processing. Even then, audio processing has never really been that intensive – how often do you find someone suggests changing their soundcard or turns down the sound settings in game because it runs too slow?

　　DS3D GX 2.0 flags the card as EAX 5.0 compliant in the game or software, and then basically emulates the effect between hardware and software. We contacted Asus and a representative explained:

　　“Our implementation is not a 1:1 reproduction of EAX 5.0. Rather, DS3D GX 2.0 allows users the choice to universally access gaming audio effects that would otherwise be locked behind specific cards and patched game titles. While we do respect the capability of a dedicated DSP processor [such as Creative’s X-Fi] to offload the CPU work, we believe performance differences will continue to diminish based on the power of today's popular CPUs. We also expect more game developers to adopt software DSP effects [Dolby Digital and DTS] for their flexibility and universally guaranteed user experiences.”

　　The “software effects” argument is what we heard from Asus at CeBIT in 2007 before it launched the Xonar D2. It is confident that, as the popularity of consoles increases and the cost of games development increases (and as a result cross-platform development becomes more common), more games will predominantly support Dolby Digital (and DTS) over Creative’s proprietary EAX technology.

　　While the Asus Xonar DS3D GX 2.0 is supported under both XP and Vista, because of the way Vista works in OpenAL, it works very similarly to Creative’s Alchemy. However the difference is that the DS3D GX 2.0 engine is agnostic and driver integrated, whereas Alchemy is a separate program that requires specific configurations for each game.

Dolby but no DTS?　　While the DTS options have been dropped, Dolby Home Theatre support is still included in full. All of these are software processed and because the Xonar D2X and DX share the virtually identical hardware, it should only take another Daniel K to engineer the DTS options to work on the DX.

• Dolby Digital Live – Encodes any audio into 5.1 channel AC3 and spits it out on the fly over S/PDIF.
• Dolby Digital Virtual Speaker – Converts stereo or 5.1 channel sound into a virtual 7.1 channel environment
• Dolby Pro Logic IIx – Upconverts stereo or 5.1 audio signals to 7.1 channels of discrete surround sound
• Dolby Headphone – “delivers realistic and spacious 2-to-5.1 surround or 3D positional sound-field over any set of stereo headphones.”

These effects do work, and I have personally found them far more effective than DTS Connect and DTS:NeoPC, however I also know people who are audio purists and won’t touch any of this with a barge poll.

SoftwareAsus introduces three audio processing features with the Xonar DX:

• VoiceEX “adds realtime gaming EAX effects to your MMOG chatting”
• ChatEX allows you to “select a background scene in VoIP chatting”
• MagicVoice “allows voice pitch changing to disguise who you are”.

Yeah, uh, no… chocolate teapot, anyone? They are probably entertaining for about 10 seconds before you realise these effects are entirely pointless. While Asus obviously has a bunch of clever engineers, when it comes to genuine feature innovation in the soundcard field we’d suggest leaving it to Creative.

　　As ever, the software looks like it was designed by someone living in the eighties trying to guess what will be popular in 20 years. It’s cluttered, unintuitive, difficult to read and just plain awful. What makes me tear my hair out is that the original CMedia Oxygen HD software was the complete opposite of this – Asus has gone out of its way to make it worse. Why? Apparently the Far Eastern markets love this futuristic and unusable rubbish, and until us Westerners can make enough noise to even have the option of changing things, it’s probably not going to change.

　　While we covered it in detail in our Xonar D2 review, new features include specific options for front panel headphone and stereo speakers and new VocalFX and Acoustic Echo Cancellation (AEC) tabs.

　　Included is also the PMP (portable media player) software which, like the Audio Centre, could be better designed. On the surface it's a simple music converter – there are better free ones on out there with far more options but the main reason to use this is because it strips out DRM. Legally. If that’s perked your ears up, we explained it in a lot more depth in our previous review if you’re interested in knowing more.

　　Well, it's more of a legal loophole – by decoding and playing the music then using an internal loopback to re-record the output it can save it without DRM. The internal digital-analogue-digital conversion does potentially lose quality, but since most DRM'd music is compressed anyway the trade off between this and freeing your music is a worthwhile one. What Asus has done though is massively improve how fast it works – when we first looked at the Xonar D2 it ran at the speed the music played, so converting entire music collections took forever. Depending on the track, the process now takes seconds.

　　We'd love and thoroughly encourage Asus to release an SDK for this to allow other developers to create more capable, open source software that uses the loopback engine. However, we also realise that currently this feature is quite "under the radar" and actively encouraging it could drop Asus into hot water with the four letter MAFIAA organisations.

Audio Performance　　The audio performance tests were done using Audio Rightmark 6.0.5 and a 3.5mm gold plated, oxygen free stereo loop back cable between stereo out and microphone input. Results were taken at the DVD sample rate of 16-bit/48KHz and High Definition 24-bit/96KHz.

What we're looking for:

• Noise Level: A higher negative is better. This is usually viewed in relation to a signal level which provides a signal to noise ratio. As you get closer to zero there's more noise and lesser audio fidelity.
• Frequency Response: Two values listing how close to the lower higher frequencies the codec can reach. If it hits them perfectly it'll display a 0, 0.
• Dynamic Range: The difference between the loudest and quietest sounds the codec can make before it distorts them. The larger the gap, the better.
• THD and IMD percentage: Closer to zero is better. THD and IMD are best looked at together, where as if you have a lot of THD and not much IMD, then it'll offer a warmer accurate sound. High THD and IMD provides a warm, inaccurate sound, low THD and high IMD gives a cold inaccurate sound and finally low THD and IMD gives a cold accurate sound.
• IMD = intermodulation distortion and is a fancy way of saying conversion interpolation, which is a basic detection of the quality loss after an analogue to digital then digital to analogue conversion. By comparing it to a highly compressed source it shows up problems with the codec and converters.
• THD = total harmonic distortion, which shows up unwanted harmonics; integer multiples of the original component sound that can be second, third, fourth degrees or overtones for example.
• Stereo Crosstalk: where the stereo channels "talk" to each other and interact. Ideally you want them entirely separate, unmixed or echoed in either channel, so a higher negative a result as possible is preferred.

16-bit / 48KHz

24-bit / 96KHz

　　Bear in mind that RMAA is dependent on the quality of input more than output since recording fidelity is usually lower and the test loops back a stereo output signal back into the line-in port. In that regard, we expect the Creative card to fair worse simply because its recording hardware is poorer than Asus’s. What's surprising is that Asus Xonar DX comes out better than the more expensive D2X, obtaining a perfect score in 24-bit / 96KHz testing. The specific results are low and all the cards are better at working with High-Definition sound than CD or DVD quality audio.

Noise Level (SNR)

Dynamic Range

Frequency Response

Intermodulation Destortion

THD + Noise (at -3 dB FS)

Test System:

• DFI LANParty X48-T2R
• Intel Core 2 Duo E6750
• 2GB OCZ FlexXLC PC2-9200
• Nvidia GeForce 8800 GT
• Seagate Barracuda 7200.9 200GB
• PC Power and Cooling Silencer 750W PSU
• Plextor PX-708A DVD-RW
• Windows Vista x64 SP1 and Windows XP SP2

Firstly for those worried about Vista x64 support – the drivers installed seamlessly and worked perfectly first time both on pre and post SP1 installations.

General Music listening

• A Perfect Circle – Thirteenth Step, The Matrix Soundtrack, Pelican – City of Echos, Death Note Original Soundtrack, St. Germain – Tourist, Rage Against the Machine and Ludovico Einaudi – Echos.

All the files were 16-bit/44.1KHz CD quality audio ranging from lossless FLAC to OGG and MP3.

　　Let me start by explaining to you my exact experience: "WOW... Oooooo..". The bass just kicks in all the right spots, the range of fidelity is precise but the quality of music is key to the experience. Using MP3s you can clearly hear the distortion and compression of the dynamic range when I really just wanted it to punch through the headphones.

　　We dug out a few audio CDs from the bottom of a draw – Feeder, Fat Boy Slim and Coldplay, and dropped them in. We couldn't fault the quality. While in comparison we had to manually set the Creative XtremeGamer to the Entertainment setting for the best response, just leaving the Xonar D2 to do what it wanted worked for us. Playing with some of the settings we have to say we're still not a fan of the Dolby DSP effects though – we're not sure if they're genuinely a value-add, although having the option to play might appeal to some. That said, we'd love to know what they add to the cost and whether we could make an additional saving buying a completely vanilla card that retains the core high quality.

Gaming – Can it really emulate EAX?

• Thief: Deadly Shadows, BioShock, Call of Duty 4: Modern Warfare and Half Life 2: Episode Two

We installed and updated Thief which features "EAX Advanced HD". When we first tested the DX a few weeks ago we couldn't get the new DS3D 2.0 GX engine to trigger EAX in any game.

　　Even without it though, the quality of output was exceptionally good – we still found Thief very enjoyable to play because it's a game you really need great audio for, but we didn't have perfectly positional audio (which is needed for a game like this, really speaking).

　　We went back to Asus and found out a patch was being worked on, and now we have it we went back to gaming to see if it has changed. Replaying the first few levels of BioShock again made us realise how much extra depth and immersion a good sound system can be – the bass, spatial awareness and audio overlap between narrator and ambient events was fantastic with Asus’s patched driver.

　　We played some Half-Life 2: Episode Two with the sound quality set to High. While it doesn't have EAX, the latest patch available from Asus enables the 5.1-channel setting. The game’s audio engine is slightly limited compared to others, however with the patch the positional audio of the Xonar DX was as you'd expect and it added to the gameplay experience. Notably it produced some lovely bass – the deep earth rumblings were particularly pleasing and the general quality of sound was certainly precise but when you've got a dozen Manhacks flying around your head the sense of depth was lost slightly because it was still hard to pinpoint them by sound alone.

　　Call of Duty 4 doesn't offer specific EAX effects but it did work extremely well with a great sense of depth and realism. The only disappointment was from the game side (like many) which was limited to a very "standard definition" 44.1KHz at its maximum setting. The explosions were very vivid and deep, and the gunshots were also well placed. Between the two, the card demonstrated an excellent dynamic range.

Value　　The Asus Xonar DX retails for around £55 including VAT, which did put it directly into the territory occupied by the Creative XtremeGamer, although we did manage to find an OEM version for just £46.07 but now they are out of stock. In fact, the best price we could find was the retail bundle for £55.71. At this matched price we'd argue that you should get the Xonar every time. However Creative's PCI-Express XtremeGamer is just around the corner and has a pre-order price of just £44.98 – a pretty significant £10 saving.

　　In respect to the £90 Xonar D2 and the £111 D2X, the Xonar DX is very good value for a virtually identical quality sound.

Final Thoughts　　The Asus Xonar DX isn't the perfect product a spec sheet would lead you to think – its software interface might be appalling and we've had to wait for a proper EAX driver to fix popular games like BioShock and Half-Life 2: Episode Two, but at least it installed without issue on various systems including boards based on Intel’s P965, X48 and P45 chipsets, along with Nvidia nForce 780i SLI and AMD 690G-based motherboards – we even used an x8 slot instead of just an x1 and as expected, it made no difference. The only problem we've heard is that there are issues with it and the 790i Ultra SLI because of the PCI to PCI-Express bridge chip.

　　The Xonar DX has a fantastic core feature set – its sound quality is largely indistinguishable compared to the Xonar D2X and it's significantly better than on-board audio. What’s more, the price to feature ratio is what makes it very accessible to buy.

　　In games (where EAX is progressively becoming less of a key feature), the quality was absolutely excellent, and now finally there are games like BioShock that benefit from the working GS3D 2.0 engine, but that's not to say that future EAX games will though. However, Asus did come through eventually and in only a few weeks, which is more than can be said for Creative's driver tradition.

　　While we may harp on about Creative's record of support and bug fixing, what would happen if someone reverse engineered Asus’s software to enable DTS effects on the DX? Or opened up the ALT for other use? Asus has also yet to prove itself on how it supports its soundcard products in the long term – it’s unclear whether in three years time, the D2X, D2 and DX will have "Windows 7" support for example. Typically most of Asus’s products have a shorter shelf-life so, yes, there's probable cause for concern, but an unproven track record is better than an established one.

　　Essentially Asus may have cut the Xonar in half but it hasn't cut out its soul – if anything this lean, mean machine is a better product than its full fat cousins. It's not a fully fledged alternative to Creative still, but it does help solidify Asus’s name in the soundcard market and you won't be disappointed if you buy one for just a shade over 50 quid.

• Performance
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• 9/10

• Features
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• -
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• 8/10

• Value
• x
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• 8/10

• Overall
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• 8/10

Asus Xonar DX

好啊，我就是ASUS的本子。我很支持ASUS

全固电容..

看起来就像是个武器库……

so long