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NwAvGuy odac 24/96 DAC review

Posted 23rd June 2012 at 07:02 AM by rjm
Updated 2nd July 2012 at 04:52 PM by rjm

I cased up my odac board (NwAvGuy via jtktam) in a small aluminum project box.

The DAC is a simple two-chip affair, with a Tenor TE7022L controller fronting the ESS ES9023 DAC and integrated line driver. A couple of voltage regulators, the clock oscillator, and an eeprom chip round out the principle component list.

I compared it with my Onkyo SE-200PCI sound card. This 24/192 (115dB S/N A-weighted, 0.003% THD 0dB 1kHz) PCI card sells for about $15,000 yen and is based on the VIA Envy24HT and Wolfson WM8740.

I'm listening to 16bit 44.1kHz .wav (CD rips), though VLC [sample rate converter set to sinc, best quality, resampling quality 8]. Windows 8 release preview [default format 24/192 (onkyo), 24/96 (odac)]. Line out though Oyaide PA-02TR interconnects to the Sapphire headphone amp, and Sennheiser HD-600s.


So, I was planning on writing up a big 'ol review with my impressions, but, well... there's not really a lot of point. I can't very well sugar coat this: the odac is not very pleasant to listen to. It's thin and hard-edged, with a headache-inducing digital sheen that frankly I haven't experienced since the early gen CD players of the 1980's.

About the only positive spin I can manage is to point out that it sounds better than the NuForce udac, which was simply distorted and noisy. The odac is at least clean and clear sounding.

Unfortunately it's also sterile and cold where it should be musical and involving.


I did a re-test, playing with the sample rates and bit depths, 16/44, 24/96 on both Onkyo and odac. Although I generally prefer the upsampled output, the difference is relatively small. I stand by what I wrote above.

While the odac has an admirably low noise floor, good stereo reproduction, and clean, accurate (to a point) sound, there is a slight "shouty" quality, a tendency to harden up on intense passages, that suggests insufficient power reserves. I also can't shake the feeling that something is not right in the ultrasonic band. High frequency transients are brittle to the point of being physically unpleasant. It's not something you can easily spot unless you have a good reference to compare to - you might be tempted otherwise to think the track was recorded that way - but I suspect the long term effect, listener fatigue, will become obvious to most people sooner rather than later.


Finally, I enabled the motherboard audio (Gigabyte GA-970A-D3, Realtek ALC889) [HD audio, set to 24/192 in Win8] and listened with my HD600s plugged directly into the front headphone jack on the PC. Onboard audio has come a long was since the bad old days of AC'97. The sound is broadly similar to the Onkyo/Sapphire signal chain. Same tonal balance, same overall presentation. In direct comparison, the bass is slightly rubbery, the stereo image is weaker and less precise, and it's missing that last extra measure of control, depth, and detail resolution. It's surprisingly, impressively close though. It takes me some seconds of careful listening to figure out which is which.

Switching between the onboard audio and Onkyo/Sapphire, it's quickly obvious that I'm listening to the same data - I hear the same things in the same way. With the odac, it might just as well have been a remastered track, the presentation is that different.

I am therefore tempted to conclude that its the odac that has issues. Could be a layout or configuration miss, could be, I suppose, that that's the way the ES9023 sounds. Either way it's not really my cup of tea.


Perhaps I should give the odac time to break in? I didn't think of that, since there were no electrolytics on the board (caps are all tantalum or ceramic SMT). Worth a shot anyway - I'll give it 24h of decoding white noise and see if there is any difference.


No. That didn't help. It seems to have opened out a little, but the fundamentals remain unchanged: Admirably clean sound, but flat and synthetic.


Ugh. Far too much time spent on this! On to other things...


1. Info on the SE-200PCI (Japanese), with measurements: here.

2. I uploaded the Rightmark results for the odac and Onkyo (Odac and Onkyo Comparison.zip). Identical results, both limited by the ADC (of the Onkyo) used for recording the signal rather than the DAC performance. In other words both DACs are as good or better than the result shown.
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  1. Old Comment
    maty tinman's Avatar
    Head-Fi Onkyo SE200PCI-LTD or Asus Xonar Essence ST? yeah, 10/21/2009
    -> Head-Fi A simple review of Onkyo SE200 Soundcard escaflo, 1/18/2007
    …The sound quality is very good, but maybe not as impressive as I hoped for. I also have a EMU 0404 USB. They sound different, and both have their positive and negative sides. It depends very much on the rest of the setup which one is preferred. The EMU is more neutral and sounds more clear. The SE-200 LTD has a touch of warmth and ads quite a bit in the mid/upper bass region. The EMU has a more open treble, but also has some harshness which the Onkyo doesn’t have.
    Posted 25th June 2012 at 05:28 PM by maty tinman maty tinman is offline
  2. Old Comment
    rjm's Avatar
    Thanks for the comment. Would agree with "The SE-200 LTD has a touch of warmth and [adds] quite a bit in the mid/upper bass region." and also note that I have a longstanding preference (bias, if you want) for warm, full-sounding audio gear.

    "Adds" is a comparative term, though. I have used the SE200-PCI for 4-5 years now and my opinion is that it can compete in terms of transparency and resolution with high-end audiophile CD players. Response [96 or 192 kHz] is ruler flat to well past 20, 30 kHz, there's no trickery involving added harmonics either. I view the warmth as the absence of harshness and grain, rather than a deviation from neutrality.
    Posted 26th June 2012 at 01:13 AM by rjm rjm is offline
  3. Old Comment
    wushuliu's Avatar
    I agree for the most part with your review, though I didn't find that unpleasant. For kicks I decided to use an external 5v linear power supply - this improved things a great deal. The 'cold' quality is still present to a degree but the overall performance is much, much improved...
    Posted 27th June 2012 at 05:12 PM by wushuliu wushuliu is offline
  4. Old Comment
    rjm's Avatar
    Unpleasant should be taken in context. For an audio component that is functioning within specification, it is on the opposite side of "enjoyable" to listen to. The harshness is relatively minor, what really drives me away is the flatness, both spacial and dynamic. It's just disconcertingly, unpleasantly odd in a way that's very difficult to explain but, as I wrote in the main post, calls to mind the hard, lifeless sound of early CD players.

    Interesting observation about the power supply. I'm not in a position to try an external supply, but that there was a significant difference suggests that internally the odac power delivery system is less than ideal.
    Posted 28th June 2012 at 12:58 AM by rjm rjm is offline
  5. Old Comment
    wushuliu's Avatar
    I understand and agree on the flat aspect. The external supply does remedy this and I have to say at this point it does sound very good. I have also read of someone experiencing issues, the odac alternating between sounding great then sound terrible with all aforementioned digititis. Perhaps the power requirements were underestimated.
    Posted 28th June 2012 at 09:43 PM by wushuliu wushuliu is offline
  6. Old Comment
    rjm's Avatar
    The board is certainly light on capacitance, and the supply is generally very spartan. In the interests of low cost the ES9023 power supply is a single 3.3V input which is shared between the DAC circuit as well as both left and right line drivers. A charge pump circuit (a kind of switching DC-DC power supply) built into the ES9023 internally generates a -3.3 V rail for the line driver circuit. The positive rail has 22 uF (shared between DAC and outputs) while the negative rail has 22 uF to itself.

    The two Micrel 5205 regulators can be fitted with bypass caps in pin 4 for low noise, but these are not used in the odac.

    Even if you powered the circuit from an external 5V supply instead of the USB, the situation regarding the regulators, charge pump, and capacitance (post regulation) is not improved, unfortunately. Perhaps strategic insertion of a couple of 100 uF OSCONs or similar on the 3.3 V supplies might help?
    Posted 29th June 2012 at 12:10 AM by rjm rjm is offline
    Updated 29th June 2012 at 12:15 AM by rjm
  7. Old Comment
    maty tinman's Avatar
    There are more users that think like you about quality sound of the ODAC:

    Head-Fi Brief Odac impressions – Page 18
    Posted 30th June 2012 at 08:14 AM by maty tinman maty tinman is offline
  8. Old Comment
    maty tinman's Avatar
    Head-Fi Brief Odac impressions – Page 22. post #234 jseaber (JDSLabs)
    …It’s not a bad batch. We’ve tested every unit and only identified 1 bad ODAC board (defective R channel). So far, all other issues have been caused by operating system glitches or cable/power problems. One customer in Norway reported that his ODAC produces odd distortion when another digital audio device is connected to the same USB hub. If you’re having trouble:

    - Try a different USB cable, with ferrite
    - Try a powered USB hub
    - Switch to a different USB port on the computer
    - Unplug other DACs from the computer…
    Posted 1st July 2012 at 09:38 AM by maty tinman maty tinman is offline
  9. Old Comment
    rjm's Avatar
    For the record my USB cable had a large ferrite on the odac end. I used it mostly with my desktop PC, but also with a netbook (winXP) both battery and AC power. Whatever variations I might have encountered under the different setups were very small. I have little doubt that my odac is a representative sample and working as designed. It's just not, in the grand scheme of things, all that good.

    By the way I was reading the datasheet for the Wolfson WM8740 DAC and comparing it with the ESS ES9023. Fundamentally the power set up of the Wolfson chip is much more advanced, four independent supply pins (DVDD,AVDD, AVDDR, AVDDL) with individual, independent grounds. No shared, integrated charge pump: the line driver circuitry is off-chip, normally powered by a separate, high quality, analog, bipolar supplies for each channel.
    Posted 1st July 2012 at 11:18 PM by rjm rjm is offline
    Updated 2nd July 2012 at 03:38 PM by rjm
  10. Old Comment
    I've listened to a new JDS Labs Standalone ODAC for about 10 hours, thus far, and despite my initial appreciation of the very high resolution it renders (as communicated offline to wushuliu), I'm just about ready to return it to JDS Labs for a refund, less a $22 restocking fee (15%), plus the cost of shipping it to them. I'd rather lose that money than hang on to it at a cost of $149.

    I've been comparing the ODAC to a Centrance DACport LX and an iBasso DB2 (balanced output). For all three DACs, I'm using the same USB cable from a Windows 7 laptop, and they are driving an iBasso PB2, equipped with LME49990s in L/R and HA5002 buffers - balanced out to LCD-2 Rev. 1 via Toxic Cables' Silver Poison.

    Just for grins, I tried listening to the ODAC with a Meier Stepdance, where I did find that, somehow, the Stepdance reduces the ODAC's irritating sheen, at least a little bit. I'm surprised by this, because I consider the Stepdance to be supremely transparent, but the ODAC is somehow smoothed by the Stepdance. Still, the ODAC remains thin and dry - not natural sounding.

    One thing I've noticed is that despite the fact that all three of these DACs are spec'd for 2Vrms output, I had to turn down the amp's volume control when using the ODAC, less so with the DACport LX, and far less with the PB2. The iBasso DB2 requires that I run the amp at a higher volume setting than I have with any other source. The ODAC requires the lowest volume setting of any source I've used. So much for specs.

    I think the ODAC would be a good match for people who are in love with an amp like the Schiit Lyr - which, in my opinion, simply doesn't resolve very well. The Lyr would smoothing its harsh transients. Unfortunately, in my opinion, the Lyr also introduces a lot of color that I find objectionable, so it's not my cup of tea - I'm just saying that I think if you like the Lyr's signature, and don't mind its lack of resolving power, it would likely do a good job of taming the ODAC. A budget DAC for a budget desktop hybrid amp.

    In short, I couldn't agree more with rjm's findings. Having found this review only this morning, it was as if rjm had read my mind. Reading your impressions has certainly clarified my own thinking.

    Right now, I'd have to say that the $299 Centrance DACport LX (natural-sounding detail, neutrality, and transparency without a hint of harshness) beats the $299 iBasso DB2 (musical and slightly smoother and darker than the DACport LX, but still very detailed) beats the $149 ODAC (what rjm said.)


    I've got several days left in which to request an RMA and exercise the 14-day return policy, so I'll give it some more time and try to remain open-minded (but subjective). :-)

    Posted 24th August 2012 at 01:21 PM by zilch0md zilch0md is offline
    Updated 24th August 2012 at 01:25 PM by zilch0md (Corrections...)
  11. Old Comment
    rjm's Avatar
    Thanks Mike,

    For the record the ODAC output is the standard 2 Vrms, and is identical in voltage level to the Onkyo soundcard I have. The output is taken directly from the Sabre chip, there no reason to imagine it would not meet the datasheet specification.

    If you had to turn down the volume, either your other DACs have slightly lower than standard output, or the subjective loudness of the ODAC is higher owing to it's rather strident tone.
    Posted 3rd September 2012 at 07:59 AM by rjm rjm is offline
    Updated 3rd September 2012 at 08:06 AM by rjm
  12. Old Comment
    I neglected to write, earlier, that I wasn't relying on my ears to gauge the difference in volume between the DACport LX, the iBasso DB2, and the ODAC - I was using an iPhone app SPL meter (JL Audio) to synchronize the levels to 85.0 dB, as measured with a lapel mic that was sandwiched between the ear pads of my LCD-2 (lying on the table as I played a white noise FLAC file.)

    It sounds as if you've measured the Vrms of the ODAC and have found that it matches your sound card, so I'd have to agree with your suggestion that the output of the other DACs is not to spec - that they were delivering something less than 2Vrms.

    To achieve 85.0 dB SPL at the face-to-face ear cups of the LCD-2, I had to adjust the volume control as shown in the following table (on my iBasso PB2, running LME49990's in L/R and HA5002 buffers, balanced out via Toxic Cables' Silver Poison to the LCD-2):

    ODAC ---------------- 5 1/3 dots = 85.0 dB
    LX ------------------- 5 1/2 dots = 85.0 dB
    DB2 (balanced out) --- 7 2/3 dots = 85.0 dB
    DB2 (singled-ended) -- 8 1/2 dots = 85.0 dB

    Thus, my conclusion that the LX and the DB2 aren't delivering the same Vrms out as the ODAC.

    After conducting the blind study, being careful to set the volume control as shown in the table for each test, my friend and I once again used the SPL meter to confirm that the same SPL could be measured at these settings, while playing the white noise file that we had used previously. We found that the SPL's were still identical, at 85.0 dB, when adjusted as shown. Even if the SPL application, in combination with the lapel mic I used, was inaccurate (too high or too low by a few dB), I can at least say that it was consistent, and thus, the volume levels were well-matched, whether they were actually at 85.0 dB or not.

    And for the record, although my ears were unable to detect any difference in volume when switching between the ODAC and the LX (leaving the volume control alone), the difference in volume when switching from the ODAC to DB2 or LX to DB2 was dramatic - a big reduction in audible volume.

    Conclusion (given that you trust the ODAC delivers 2 Vrms): The DB2's Vrms was well short of meeting iBasso's published spec.

    Thanks again, for your impressions of the ODAC - I agree completely with how you describe what you were hearing.

    Posted 3rd September 2012 at 12:53 PM by zilch0md zilch0md is offline
    Updated 3rd September 2012 at 12:56 PM by zilch0md (alignment of the columns in my table)
  13. Old Comment
    rjm's Avatar
    Adding two transducers (headphones, mic) in the measurement path will adversely affect the precision of your measurements. Within error I think its safe to assume the ODAC and LX are equal and to spec. Normally you'd run a 1 kHz sine wave test file and measure the output with a RMS voltmeter ...

    The DB2 unbalanced output is only 1 V rms, so it will be 6 dB lower SPL, all else equal. Depending on the BAL-UNBAL conversion in the headphone amp, the balanced output, rated at 2 V rms, may also be attenuated.

    Thus: everything is performing as expected.
    Posted 4th September 2012 at 03:00 AM by rjm rjm is offline
    Updated 4th September 2012 at 03:05 AM by rjm
  14. Old Comment
    RJM - not sure I agree with your measurement comment "Adding two transducers (headphones, mic) in the measurement path will adversely affect the precision of your measurements." . If you are subjectively listening through the same headphones and amp but only A-B switching the DACs at the same measured output SPL with all other things equal, the comparison would be valid.

    Mind you, a true A-B test should be performed within a few seconds maximum as our audio memory is short which I don't imagine one could reliably do with DACs on the same PC.
    Posted 24th September 2012 at 08:41 AM by elmura elmura is offline
    Updated 24th September 2012 at 09:04 AM by elmura
  15. Old Comment
    rjm's Avatar
    Sorry, I don't follow. This isn't subjective listening, we just want to compare the output level of the DAC stage for a standard input. This is best done by directly measuring the output voltage for each component.
    Posted 25th September 2012 at 12:16 AM by rjm rjm is offline
  16. Old Comment
    According to my crude measurements the ODAC exhibits a phase wrap at 2kHz. That may be what is setting it apart in your listening tests.

    Click the image to open in full size.

    I had the USB driver distortion problem as well. It came on suddenly and went away after I used a different port.

    All in all I hate bashing the ODAC because it does great for the price but it leaves a few things to be desired.
    Posted 19th November 2012 at 09:44 PM by boris81 boris81 is offline
  17. Old Comment
    rjm's Avatar
    That looks ... unhealthy. I wonder what could cause something like that? It would surely have to be something in workings of the DAC chip or its configuration, I can't think of anything in the purely analog domain that could cause it.
    Posted 24th December 2012 at 05:39 AM by rjm rjm is offline
  18. Old Comment
    Bas Horneman's Avatar
    Quite good for the money. But relegated it to pc duty. Where it drives my lm3886 gainclones. Lots of detail. I have to admit in my main system I find it does have a "digital" sheen
    Posted 18th February 2013 at 08:34 PM by Bas Horneman Bas Horneman is offline
    Updated 18th February 2013 at 09:19 PM by Bas Horneman
  19. Old Comment
    dimkasta's Avatar
    I recently modified one for a friend isolating the +5V from the USB cable (cutting the pcb track) and using a salas BiB for the power supply.
    Quite an improvement.
    Posted 17th July 2014 at 10:17 AM by dimkasta dimkasta is offline
  20. Old Comment
    Originally Posted by dimkasta View Comment
    I recently modified one for a friend isolating the +5V from the USB cable (cutting the pcb track) and using a salas BiB for the power supply.
    Quite an improvement.
    Could you describe in what way did the mod improve the sound?
    Posted 25th October 2014 at 09:59 PM by hallom hallom is offline

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