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Re: Let's compare numbers and see why mine are different from yours

You have reported in the past that the same sound arriving at one ear 5 microseconds apart from the other can affect our perception of localization of that sound. For the sake of this discussion, I will accept that as a fact.

"Localization numbers in the 5 uSec time range would seem to indicate that imaging requires much greater bandwidth to remain stable across the audible band."

I don't see how you drew that conclusion. A sound with a period of 5 uSec has a frequency of 200 khz and a sound with a rise time of 5 uSec has a frequency of 50 khz. Both of these are far beyond the range of human hearing and far beyond what exists on all but the very rarest of recordings specially made to contain them. The conclusion of your experiment it seems to me relates to placement of microphones, maintenance of channel to channel timing relationship integrity, and the geometry of speaker placement and listener location, not bandwidth. Two sounds at ANY frequncy can be arranged to arrive with a difference between ears of 5 microseconds.

I still don't see how John Curl's conclusions about the specification for slew rate relates to actual performance of phonograph cartridges and actual acceleration of styli due to change in stylus velocity/dt (maximum stylus acceleration) relates to real world recordings and phonograph records. It seems to me he's made exactly the same mistake virtually all audiophiles make, he's taken two entirely different situations, namely two very different preamplifier circuits, focused on the one variable he's interested in proving is significant, ignored all of the other variables he's effectively altered, and ascribed what he hears as an improvement to that one variable. In other words his logic and arguement are IMO flawed. To convince me, he'd have to create an experiment to compare two circuits using much tighter controls where the maximum slew rate was the ONLY variable to be accounted for between them. And then he'd have to demonstrate that there was less measured waveform distortion within the audible passband which could be reliably correlated to what is audible in DBTs. (I'm a stickler for rigorous proof in a field where wild claims are routinely offered as facts.)

I will agree that slew rate limiting can result in audible distortion. This exposes the fallacy of judging the performance of analog electronic amplifiers by considering their 1 watt frequency response into a resistive load when they are actually used up to full power into reactive loads. I'd expect something akin to limited gain power bandwidth product to be the culprit and FR testing into reactive loads similar to loudspeakers up to rated power to be much more informative but that has not been the customary practice. The same could hold true with preamplifier FR looking for distortion due to slew rate limiting in stages ahead of the volume control since the input signal can significantly exceed the preamp's rated sensitivity at maximum gain, the input level probably usually used customarily for FR measurements. It was interesting in one article I read recently on the internet about TIM that it was reduced in one instance by increasing negative feedback, not decreasing it. This makes sense to me since one benefit of negative feedback is increasing bandwidth.

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