Pat Farrell;169633 Wrote: > > This is not an example of phase changes. > And square waves are special, they have infinite frequency. >
Sorry, I should have explained in more detail. When you send in a square wave (or an almost square wave if you're really worried about the high freq. stuff - just cut it off, it's not relevant here), or any other signal, to a standard crossover, there is a phase shift of nearly 180 degrees between low and high frequencies (relative to the crossover frequency). That turns square waves into something which - in the time domain - looks very little like a square wave. I've attached an image showing this (red is input, black is output after the filter). My question is, is that audible or not. > > I believe, IMHO, etc, that Phase truth is the key to audiophile sound. > > > There are two senses to this question. One is absolute phase for the > whole frequency spectrum. There are theological discussions about > this. > A kick drum's sound comes towards the audience when the drummer hits > it. > So some folks argue that the first wave of the kickdrum hit from your > speaker has to come towards you. I"m not convinced of this one. YMMV > > The second is the relative phase as frequency varies. Crossovers, EQ, > etc. have different phase impact (or destruction) at different > frequencies. I believe these are critical to realism. > OK, thanks. To clarify, I'm asking about relative phase - I don't believe in absolute phase differences, at least not in any kind of sound I care about. > > The probability that you can get six of anything and have them all > keep > the phase properly aligned between them is vanishingly small. > > Digital EQ that maintains phase across the frequency sweep is very > hard > and very compute intensive. Doing that is expensive. Gonna cost more > than several SqueezeBoxes. > > DEQX costs about $3750, so yeah, quite a few SBs... +-------------------------------------------------------------------+ |Filename: LRsq.jpg | |Download: http://forums.slimdevices.com/attachment.php?attachmentid=2244| +-------------------------------------------------------------------+ -- opaqueice ------------------------------------------------------------------------ opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=31590 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/audiophiles
