pfarrell;371117 Wrote: > Patrick Dixon wrote: > > 'Good' and 'Bad' is not science ... and neither is not being curious > > enough to try stuff for yourself :-) > > I see the smiley, but its not enough to keep you from edging close to > personal attacks, which have no place in a serious discussion. > That's not a personal attack at all, I'm pointing out that at lot of science comes from people being curious and trying to explain things they observe but don't understand. I don't think it's science to stand around demanding that someone else provides proof for you.
pfarrell;371117 Wrote: > > > > I'm not sure what you mean by absolute amount in ps ... time is > > continuously moving and so it's only ever relative isn't it? > > I mean if say 10 ps is important, is that the same for all streams? > Does > it matter if the stream is red book and working at 1,411,200 > bits/second? Does the "important" value change if you are doing high > rate and/or wide? > > So individual bits in a RedBook signal are on the order of > microseconds. > (10E-6) Its likely that errors on the order of 100 nanoseconds (10% of > the signal) are important. Even 10s of nanoseconds (a percent or two) > is > intuitively possible to have an impact. Single nanoseconds, now you are > pushing below what is intuitive. > > > Time may be absolute, but folks working with audio signals don't care > much about signals out of phase by a few milliseconds, as humans can't > hear that as separate, or our brains merge them together. > > At the speed of light, a pico second is about the size of a piece of > pepper, from the classic speeches by Grace Hopper. A nanosecond is a > bit > under a foot. > > The folks working on the LHC (Large Hadron Collider) care a bunch about > time frames that are much smaller than I can imagine. So while I'll > agree that time is fixed, our understanding of it varies. > > > You have to determine what amounts are important to you - it's like > > noise, what amount of noise is important? > > No, I don't agree that I determine what is important. Its is widely > accepted that noise more than 100 dB below the signal can't be heard by > humans. You can measure it below that, but it makes no difference. > > To be explicit, if one amp has a SNR of 100, and another has a SNR of > 103, then one is better by measurement, but the difference makes no > difference to the ears of people listening to either. It may make a > difference to the purchaser, bragging rights and all that. > > Its not a personal question, its one of measurements. What variations > (absolute, relative to something else, etc.) are detectable by enough > folks to allow us to say its science? > > -- > Pat Farrell > http://www.pfarrell.com/ You completely missing the point - to say that one amp is better because it has a SNR of 103dB rather than 100dB is nonsensical because it depends not only on the level of noise but it's character too. The same goes for jitter. Whilst is lovely and clear to reduce everything to single number and state that above is 'good' and below is 'bad', that's not how things are in our wishy-washy human world. -- Patrick Dixon www.at-tunes.co.uk ------------------------------------------------------------------------ Patrick Dixon's Profile: http://forums.slimdevices.com/member.php?userid=90 View this thread: http://forums.slimdevices.com/showthread.php?t=56425 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
