Audible Differences in DAC's? Options

[sawdin]

When he announced the release of the ODAC, NwAvGuy posted the the following on his blog:

NO SNAKE OIL REQUIRED: Many audiophiles want to believe more elaborate or exotic DACs offer higher fidelity. The ODAC demonstrates you do NOT need any of these for 100% transparent performance:

Asynchronous USB
UAC2 (USB Audio Class 2) Support
Asynchronous Sample Rate Conversion (ASRC),
Minimum Phase Filtering (no pre-ringing)
Non-oversampling NOS DAC chips
Dual DAC chips
Balanced Outputs
Vacuum Tube Stages
Elaborate and/or High Current Power Supplies

Is his position accurate/defensible?

If there was a well-designed DB/ABX test of the ODAC and sub $500/$1000 DAC's (e.g., Audioquest Dragonfly, iFi Micro iDAC, Audioengine D1, Emotiva XDA-2, etc.) that are are Asynchronous, USB Audio Class 2, etc. etc., do you think there would be 'audible/discernible' differences?

The reason that I am asking is that I am curious as to the whether there really is much of an audible difference between various sub $500 or $1,000 DAC's, and I haven't come across any DB tests of DAC's. I have read many subjective reviews that claim differences are quite noticeable. Of course, there are major differences in terms of the types and number of inputs and outputs that a DAC may have, whether they include a headphone amp, how portable they are, etc.

I am not trying to start a fight/flame war, I am just curious as to what the 'prevailing wisdom is' on this site. If you think there are differences in sub $500/$1000 DAC's, what do you believe are the relevant factors (e.g., USB vs Toslink/Coax)? I know that 'speakers' make a difference, but am unsure about how much, if any, difference there is between DAC's. Again, just trying to become an informed consumer (and save $), not trying to start fights.

TIA

PS...I should note that I appreciate people like NwAvGuy and others who try to provide quality products, diy options, etc., at reasonable prices.

[mzil]

Agreed. However a FIIO E3 plugged into a UCA 202 gets you there for less than half of that.

If I am understanding you correctly, you are suggesting bypassing the built-in headphone out already found on the UCA-202 and instead using its line out to the Fiio E3 to drive some headphones?

BTW I made a typgraphic error above. I meant FIIO E5. I had to look at the one on this computer to refresh my memory! ;-)

Yes. The headphone jack on the UCA 202 has a source impedance of about 50 ohms which can lead to audible frequency response changes with some headphones.

The Fiio e5 is said to provide a source impedance of less than 1 ohm:

http://nwavguy.blogspot.com/2011/03/fiio-e...dphone-amp.html

^There is (or was) an E3, but it lacks a volume control and is not well thought of by nwavguy, so I wasn't sure what exactly you were suggesting. Thanks for the clarification.

Regarding the Behringer UCA202's output impedance spec of 50 ohm for the UCA202 and driving low impedance headphones, I suspect the importance of strictly adhering to the "1/8th rule" is a bit exaggerated. He only shows a worst case scenario, his Ultimate Ears SuperFi 5 Pro, and from there scares everyone into accepting this rule as gospel. I really wish I could see more curves than just that. For all we know the amount of deviation plummets with a conventional, non-balanced armature design with a similarly low impedance, or if one accepts deviations of say +/- 1 dB as being relatively benign (considering the much larger, comparatively rollercoaster curves of different headphones in general, one model to the next), his "rule" becomes more like "1/2" or "1/4" , for all we know. Your thoughts?

This post has been edited by greynol: Mar 14 2013, 01:53

Reason for edit: Added quote which links to the original discussion for context

[saratoga]

I really wish I could see more curves than just that.

Heres another 30 or 40 devices and a bunch of headphones:

http://rmaa.elektrokrishna.com/index.php?dir=Comparisons
http://rmaa.elektrokrishna.com/index.php?dir=Single_Players

For all we know the amount of deviation plummets with a conventional, non-balanced armature design with a similarly low impedance, or if one accepts deviations of say +/- 1 dB as being relatively benign (considering the much larger, comparatively rollercoaster curves of different headphones in general, one model to the next), his "rule" becomes more like "1/2" or "1/4" , for all we know.

I'd say hes quite conservative. The impact of output impedance is enormous, and it factors into more then just frequency response (see THD at 1/2 vs. 1/8 for instance).