Triode wrote: > I would suggest you need to be careful making blanket statements such as > this. At best this is a statement of what you hear in your system and > at worst its possible that you have an expectation bias of the changes > (cf your assersion that EDO 0.7 and 0.6 are vastly different... or > tuning buffers beyond their max value makes a difference...) > > I think what we can say is that in any computer based music system there > may be some level of cpu activity related noise which is present on the > power rail/ground plane. Whether this can be detected on the output > interface will be hardware design specific and what impact this has on > the downstream components will be very dependant on the construction of > the downstream component. In this case it sounds like your usb-spdif > device is suseptible to noise on the usb interface. Its likely than > many well implemented async usb dacs may be less suseptible, others will > be. > > However the assersion that Touch is worse than a PC is a blanket > statement which I don't think you can stand by. It will depend on the > PC, its operating system and specifically the output interface hardware > and its power rails. There is simply too much variablity there to be > able to say that it will be inheriently better or worse that Touch. > > As for how the touch output process influence sound quality - I suspect > that the main issue here is that there is so little going on within > touch that you can detect the impact of indiviual software > processes/tasks on the power rails. On a generic PC there will be many > more active threads and so I suspect the background cpu activity/noise > is far more diffuse. However if you look at specific outputs such as usb > then you will see regular interrupts which are handled by the kernel in > just the same way as touch (everything uses ehci based usb chipsets for > instance). There will also be application layer things which can be > tuned, but the impact this has on the output will be very dependant on > the hardware implementation. > > To summarise - I think the best you can conclude is that with your vlink > 192 you can detect more noise from Touch than from your PC. I don't > think this should put people off using the touch - it may mean they want > to look at true asyc dacs (where there is a fixed clock is next to the > D/A converter and there is no spdif/pll)
re "I think the best you can conclude is that with your vlink 192 you can detect more noise from Touch than from your PC" or as I put it the Touch is too noisy would be interested if you could get the usb irq frequency down from 2500 hz, to me this goes some way to explaining the thin digital EDO sound or is it the vlink 192 that is causing the irq frequency to be so high ? ------------------------------------------------------------------------ SBGK's Profile: http://forums.slimdevices.com/member.php?userid=52003 View this thread: http://forums.slimdevices.com/showthread.php?t=94855 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
