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I appreciate your feedback and critique. I used to have the QB9 and indeed it is a nice DAC so was quite happy that Stereophile's measurements concurs.

For this article, I believe the data was "bit perfect" since the LSB jitter modulation was evident in the 16-bit tests. Due to the hardware limitations, this was of course not seen in the 24-bit graphs. I did discuss this fact and the issue that the built-in computer DAC's had problems with bit-perfection.

Thank you for bringing up the "skirt" issue. I'm going to have to update my ASUS Essence One measurements because this was worse with the USB input but not the coaxial or TosLink. However, most of what I've seen suggests that this low frequency jitter is masked by the primary signal. Please correct me if this is wrong so that I may pay more attention to it especially if there's a point of audibility.

As for "at some point you have to listen to the damn thing" (I'm directing this to the general viewership, not just to your comments). It is precisely because I've been listening AND reading forums like this for the last 15-20 years that I started doing the measurements and putting up the blog! I don't think it's at all a stretch to say that people are notoriously unreliable in their experience... I have never found an audiophile who could reliably differentiate high bitrate MP3 for example, yet when I ask, everyone seems to say they can (sure there are people who can ABX 320kbps but that's very few). For those who have a copy, listen to track 26 on Stereophile Test CD2 simulating 10ns jitter. I would estimate that half of the audiophiles I've tried this on over 50 years old have difficulty hearing this simulation on a test tone yet they universally claim that a few hundred picosecond jitter is a "problem" audible in actual music.

There's precious little objectivity out there anymore for audiophiles - look at that bizarre 3-part article on computer audio in TAS early 2012; if "everything's possible" (bit-perfect rips sound different if ripped at different CD speeds according to that article) then nothing is known anymore. Just look at the numerous comments when those new to computer audio asks straight forward questions here. IMO, some of the responses border on delusional.

Time is limited but I have spent many many hours listening to cheap to very expensive gear - even owning a few of the more expensive items over the years. It is my belief that "good" sound can be independent of factors like price, or any of the external factors like workmanship, etc. In fact, I've come across situations where high priced gear are just plain inaccurate. For me, accuracy is all that matters, and this can be quantified objectively.

Speaking of "misinformation is what is sending most people into shock when they start CA". Realize that over these months of testing, I have not advocated anything I would consider as "fringe". I've shown that asynchronous DAC's are better with less anomalous J-Test spectra, coaxial and good USB is better than TosLink in the gear I have, shown 'good' DAC's like the Oppo BDP-105 (ESS Sabre) measures superbly. I advocate for "bit perfect" and showed that both Windows and Mac are capable of accurate output, and have interspersed these tests with listening to make sure nothing appears awry - usually spending a couple hours at a time in the evenings listening (eg. when I was doing some cable measurements recently). As I've said in some posts, there is no voodoo or magic here, and the tests are showing me such. How in the world is this shocking anyone out of computer audio!? If anything, it's reassuring that measurements line up with a rational empirical approach that is reproducible.

Now as for the test gear I use and software like RightMark. You don't need the Hubble telescope to identify Jupiter in the sky. Likewise, why do I need expensive gear like an AP when I just want to make sure the frequency response is relatively flat, or that the dynamic range of a DAC can exceed 16-bit CD quality, or that the Dunn test isn't atrocious? All these things are within reach of what I have and the beauty of computer audio and technological advancement is that stuff that can do this is easily within the consumer's grasp. However, I'm not saying that anyone should do this since it has taken me countless hours to learn how to get the calibration right and make sure the software setup works for me in order to achieve a high level of reliability in the measurements.

When my simple setup can easily demonstrate analogue cable differences, XLR vs. RCA differences, show me the spectral smearing between 320kbps MP3 vs. 400kbps AAC, demonstrate J-Test differences between coaxial vs. TosLink vs. AES/EBU, when I post about this, in what way is this "misinformation"? In fact, my ASUS Essence One measurements showed a disturbing anomaly when upsampling is used resulting in attenuated frequency response which has since been confirmed by ASUS (and hopefully to be remedied)... How come subjective Essence One reviewers missed this when it was so obvious with just a little testing?

Look guys, ultimately either what I say and write about makes sense, or it doesn't. I mention a new post up here once awhile that could be of interest like this one with the laptop tests to outboard DAC's. I have ZERO financial interests or otherwise. I do it for fun, for my own education, and enjoy sharing what I've found with others. Anyone can freely share their thoughts in the comments section (haven't had to censor anyone at this point for nonsense), and I've invited people to give me evidence/reason if they think something I say is wrong. Of course, with my objectivist mindset, "Level 4 or 5" evidence (ie. individual or series of reports) doesn't really impress compared to experimental results or controlled trials.

Archimago's Musings: A 'more objective' audiophile blog.

Edits: 04/21/13 04/21/13

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