jkeny wrote: > > The really interesting part, for me, is what audible benefits the > improvements in USB signal quality are providing. This improvement has > been measured & can be seen in John Westlakes' plots. > Amir's measurements are by no means comprehensive which he states > himself so the audible improvements remain unmeasured & as John Westlake > states, will probably not be revealed in analogue measurements. > > Archi, I know you are a great believer in measurements - have you ever > heard an improvement in audio that you could not measure?
Hi John. Let's focus on the comments above. Firstly are we talking about '-improved eye-pattern-' (http://www.pinkfishmedia.net/forum/showthread.php?p=2680112#post2680112)? I see that Westlake has been 'critical of the Regen's stock SMPS' (http://www.pinkfishmedia.net/forum/showpost.php?p=2689811&postcount=192) as well as demonstration of high 8kHz noise current in the USB power pins! So there doesn't appear to be any improvement in noise if one is arguing about the 5V line with the stock device. 1. So, if we discount the SMPS as not likely to be improving sound quality and therefore the majority of potential sonic improvement is from the more precise eye-pattern, -by what mechanism do you think this would happen-? I'm happy to stick with the "bits are bits" argument and suggest that if there is no data corruption from a computer's USB data line, then it is unlikely there will be a sonic difference at all. Sure, maybe the cleaner Regen data line out has less noise - but I would expect the 8kHz tone to be measurably reduced not increased if this is part of the noise reduction. And as for timing accuracy because of better eye-pattern precision, well maybe if I run an old isochronous DAC this could help with lower jitter... But asynchronous USB DACs are ubiquitous these days so I don't see a problem. 2. John Westlake says differences won't be revealed in the analogue measurements - *-WHY-*? Why is he not wrong? It is the analogue outputs we're sending to the preamp/amp/speakers is it not? Unless there's some other perhaps magical mechanism by which sonic information is getting to my amp and speakers, I would very much like to know how this is achieved. 3. The general question... "I know you are a great believer in measurements - have you ever heard an improvement in audio that you could not measure?" That's a hard one to answer because I generally don't question every sound I hear or analyze it to death! I post and measure for fun and hopefully achieve some understanding into my hobby. I see contentious -beliefs -over the years stated as almost foregone conclusions and thought it would be fun to explore these "uncertainties" in a blog. I accept that there are things *very difficult* to measure... For example, it's not possible for a typical hobbyist to measure all the parameters of one's speaker system although one can get a grasp of some of that. (I'm happy to read what Olive and Toole have to say!) But there are things which I don't think are all that difficult to understand - cables, DACs, bitperfect outputs "sounding different", OS's sounding different come to mind and can be explored. And in these cases, no, I don't think I've noticed anything all that mind-blowing, deviates from scientific thinking of how the engineering works, nor subjectively have I experienced an "improvement" or "deterioration" that didn't correspond to measurable effects. I would place the claims about the Regen (and Jitterbug) in the same category of tweaks that are unlikely of benefit... And even if they are of benefit in certain situations, would likely be because the DAC is poorly engineered in the first place. I appreciate that some folks are excited about the product and the testimonies are impressive on some forums/threads, but after all these months, all these discussions, and no clear concept presented for mechanism of action and in fact some results questioning whether it's even beneficial, I really cannot get excited at the low prospect of benefit in the form of improving fidelity of one's USB DAC. Archimago's Musings: (archimago.blogspot.com) A 'more objective' audiophile blog. ------------------------------------------------------------------------ Archimago's Profile: http://forums.slimdevices.com/member.php?userid=2207 View this thread: http://forums.slimdevices.com/showthread.php?t=104340 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
