ASUS Xonar Essence ST/STX soundcards Specifications

Sidebar 1: Specifications

Specifications: Soundcards compatible with PCI (ST) and PCI Express (STX) personal computers. Windows operating systems supported: XP, Vista, 7. Sample rates supported: 44.1, 48, 96, 192kHz. Bit depths supported: 16, 24. Dolby Digital and DTS decoding supported. Analog outputs: line on RCA, headphones on ¼" jack. Analog inputs: line/microphone on ¼" jack. Digital output: electrical and optical S/PDIF on RCA jack with coaxial TosLink driver. Maximum output level: 2V, line output. Headphone output level & impedance: optimized for headphones with impedances of 32–600 ohms. Frequency response: <10Hz–90kHz, –3dB (96kHz sampling). THD at –3dB: 0.0003%, line out; 0.001%, headphone out. Signal/noise: 124dBA, line out; 110dBA, headphone out. A/D input S/N: 118dBA. A/D input THD at –3dBFS: 00002%.
Serial Number Of Units Reviewed: 93COAI098346 (ST), 93COAI019499 (STX).
Price: $199.95 (each). Approximate number of dealers: >150 on-line dealers.
Manufacturer: ASUSTeK Computer Inc., 15 Li-Te Road, Peitou, Taipei 11259, Taiwan. US distributor: ASUS Computer International, 44370 Nobel Drive, Fremont, CA 94538. Tel: (812) 282-2787 (support). Fax: (510) 608-4555. Web: usa.asus.com.

COMPANY INFO
ASUSTeK Computer Inc.
US distributor: ASUS Computer International
44370 Nobel Drive
Fremont, CA 94538
(812) 282-2787
ARTICLE CONTENTS

COMMENTS
Xavier Xerxes's picture

John,

Thanks for your review.  I would like to use the digital and analog output connections at the same time: digital for my home theater 5.1 experience and the analog to be connected to a 12-zone amplifier.

 

Is it possible that both digitial and analog output signals can work this way?

 

Thanks!

Andrei's picture

I am running two of these beasties.  One an ST and the other an STX.  For my part I have never had a problem with either playing resolutions of 44.1, 48, 96, & 192.  Sound quality was already good and took a giant leap forward when I upgraded the op-amps (a very cheap exercise).

Now the tricky subject of resolutions of 88.2 Khz and 176.4 Khz.  In fact there is a workaround.  If you have the free Audacity software it can be done.  Audacity is one of those freeware programs that are just outstanding.  What you do is this: (1) you simply load the track to be played.  (2) you play it back in Audacity.  So you do not use Foobar or MediaMonkey or Windows Media player or the like.  Now here is the curious thing: when using Audacity for playback it actually sounds better than even Foobar, my current favorite.  Audacity is a progarm for manipulating sound, rather than playback, but it naturally has a playback feature so you can hear the effects you have done.  What I think is happening is this:  Audacity rips the track into memory as some sort of wav format and hence the bit-rate / resolution is no longer relevant.

While I am on this subject: I found a small improvement by running a co-axial into a dedicated DAC.  This is not really necessary and hardly justifies the expense because the Xonar ST and STX already have excellent DACs.  The cost is a lot because you will need not only a better DAC but the cabling has to be good too.

Mirko's picture

Thanks for the great and informative review.  I bought this sound card with the intention of streaming spdif out to my pioneer 09tx so I could listen to high def FLAC on my stereo system.   I had no idea that the quality of the card actually makes a difference when using spdif out.  Which is contrary to what most people write about spdif.  Often you read that it doesn't matter and that bits are bits.  But i found this actually isn't the case.  If you don't believe me, try for yourself.  I thought I could live w/ my motherboards Realtek spdif out to my receiver and let the receiver  do the decoding.  But noticed that My realtek spdif sounded like crap!!! ESPECIALLY when comparing against the sound files the receiver decoded from usb or the ipod dock.  So I considered an external DAC, but I know that my receivers dac uses wolfson 8741 chip which Is already good. Anyway, after hooking up this asus bad boy, i was blown away by the worldly difference in sound that it made.  Setting the output on the card to PCM 192khz and I'm all set.  Mission accomplished.  But that's not all.  After comparing the analogue sound of the card, i was again, quite impressed...which one did i like better? My receiver to decode or the asus PCM chips?  i did A/B comparison with the asus doing the decoding versus the pioneer by running a long 1/4" jack and setting the volume level the same between the two.  Let me tell you, for 200 dollars, this asus card does a seriously good job providing a crisp clean and open analogue signal to your ears. I still prefer the my receivers dac by wolfson chips.  The sound is a little more smoother and less harsh to my ears..it's different but not better.   But I killed two birds with one stone on this one.  For two hundred dollars I got an excellent digital transport to my receiver, and high end audio analogue outs from my computer that are clear, clean an extremely quiet.  Very happy customer here.  To think that there are people out there running spdif from  crappy cards to thousand dollar external DACS is sad to me.  Maybe I'm wrong..anyway.  Awesome card.  Awesome buy.  Killer sound.  Makes me wonder if I would be able to discern the difference from this card and the essence one.  

Mirko

Andrei's picture

Hi Mirko

I agree the sound quality is really good.  My other Source is a Cambridge Audio 650BD (not counting a turntable). Overall the Asus Xonar ST eclipses it by a tad.  The comparison is a bit tricky though because (i) I have upgraded the op-amps; (ii) the CA 650BD does play DVDA and SACD.  But on an Apples to Apples Comparison CD vs Flac at 16bit 44.1 Khz : the Asus Xonar card is a smidge better.  It becomes even better when I play flac files at 24bit and 48, 96, and 192 Khz.  On the other side the CA650BD is a bit better when playing DVDA and especially SACD.  The CA 650BD is not high-end to be sure but it is not bottom end either.  I think for 'spare change' the Asus Xonar cards are simply fabulous.  Why anyone would buy a Music Sever when they can have this card?

Initially I used the RCA connections direct to the AMP.  Then I tried SPDIF optical, and USB into an external DAC.  Finally I tried SPDIF coaxial into an external DAC.  USB was easilly the weakest and SPDIF via co-ax is easily the best sound quality.  The caveat is that you do need good cables.  

Andrei

Andrei's picture

Oops.  Ignore the USB comment above.  I actually have two of these soundcards, or rather an ST and an STX.  With the STX that I use in my office it is connected to Bowers and Wilkins MM1 Desktop speakers.  They have the USB connection option to the PC.  With this Soundcard I connect via a RCA to Stereo plug.  It is this USB connection that I had tried and is not as good as using the Asus Xonar soundcard.

Andrei

hollowman's picture

Selecting 192k Sample Rate in Xonar's Audio Control Center gives best performance of std. 16/44.1 in my tests. Wish the Control Center allowed more direct DAC control, such as selectable digital filter (Slow/Sharp) and phase reversal. 

Agree that this Card is a decent value. Since Asus decison-makers (and Asus' direct competitors, like HTOmega) are probably reading these comments, here are three suggestions for future products:

1. Use dual DACs in diff mode

2 Use better DACs, such as ESS Sabre

3. Design/offer more advanced firmware filters (prefer. user selectable) and upsampling. This may be via decoder DSP or simply selecting amongst those innate in DAC chip. E.g., Min. Phase, Apodizing, etc. Also allow selectable upsampling.

That's all! #3 requires no costly PCB/topological redesign -- it's just software code re-writing. #1 and #2 can be done w/o too much PCB redesign. The Sabre chip maybe $20-30 more, but I'll be glad to pay that for the huge gain in performance.

Thx for your attn.!

Shalmaneser's picture

I'm looking for cable advice for my Essence STX II -> Yamaha CX A5000 connection. I don't have anything local for easy comparison. I don't go for marketing of oligonucleotides injected into titanium mono-filament cables jacketed with carbon nano-fibre woven kevlar bulletproof sleeves. (lets keep it somewhere under $6 a foot.)

Shalmaneser's picture

Does anyone have a guide to the various opamps that are usable in the STX II? I can't even find anything that characterizes the included/extra opamps that ship with the STX II. Thanks!

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