Rodney_Gold;312787 Wrote: > Well it has to be something thats happening to the digital signal, tho > at what stage and what affects the signal is beyond me. I'm a natural > sceptic and not prone to snake oil stuff , butI have directly AB > compared various sources etc into my system , which is actually easy to > do , considering my speakers have 2 digital inputs and my Z-sys also has > seamless switching between digital inputs and have heard differences , > whether its the DAC in my speakers doing this or not, I have no idea , > but considering its the same dac used , the only conclusion I can > gather is that its something to do with the digital signal itself. Now > to take this one step further , the addition of a meridian 518 in > Bypass mode, where it merely de - jitters (so they say) the signal , > makes a difference and anyone with one can confirm this - the signal is > still the same info , yet it has changed somehow (Im not talking any > upsampling of wordlength or adding any dither here) > My z-sys that can convert a 16 bit sample to a 24 bit one also sounds > audibly different when you do so , yet the info that comes out in terms > of 1's and 0's still has to be the same , the extra bits must be > empty......?? > Initially , 44/16 sound was touted as perfect sound forever , and as we > all know , that was not true. > Ppl plainly do hear differences and one cannot ascribe these to merely > a placebo effect as many are wont to do.
Rodney, Robin beat me to it in pointing out that the SPDIF signal is indeed a variable mark/space squar(ish) wave. A static sine wave can only convey frequency and amplitude!. I'm sure you are hearing differences as you pass the digital signal through various pieces of gear...but it's mostly not because the bits are changing. The output from an SB/TP is 24-bit anyway, regardless of the source. This is about timing/jitter/clock recovery at the point at which the digital signal is converted to analogue. As the clock is made easier/harder to recover (and there are many factors at play here) and jitter goes up/down there will be real differences in the analogue output (ie the sound). No question in my mind about that. Also the impact of various forms of electrical noise on the analogue circuits of the DAC will have an effect. So no IMHO it's not the digital signal per se that is the problem nowadays...it's how we turn it into something we can hear. Transports can affect the sound even though logic would seem to say they can't. I believe this is because of two factors: 1) different transports have different quality outputs (not digital quality - I mean the square wave is cleaner/noisier) that make it harder/easier for a DAC to process 2) transports can inject noise onto the digital signal path that gets into the analogue parts of the DAC As far as I can tell, the SB kit is pretty good in both respects to start with, although there is some debate about this. Certainly it seems possible to make the SPDIF "squarer" by tweaking the circuit slightly, as documented elsewhere. What difference it makes, I don't know. Everybody's MMV - this is just my personal view Regards Phil -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal...SB3+Stontronics PSU - Altmann JISCO/UPCI - TACT RCS 2.2X with Good Vibrations S/W - MF X-DAC V3/X-PSU/X-10 buffer (Audiocomm full mods)- Linn 5103 - Linn Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Townsend Supertweeters, Kimber & Chord cables ------------------------------------------------------------------------ Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=48900 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/audiophiles
