JIJ3;557978 Wrote: > John may correct me if I'm wrong, *but another huge benefit of the Touch > over the USB adapter is the fact that the Touch's ethernet interface is > completely asynchronous* with the computer. *The USB interface on the > other device is likely not asynchronous*, and jitter level will depend > to some degree on the computer itself. *I don't know the details of > this other device,*...
Hmmmm... "...another *huge benefit* of the Touch over the USB adapter is the *fact*..." You do not know the actual details, but it is easier to assume that the other device is "likely not asynchronous"? :) Google is your friend. :) The USB interface on the "other device" *is* asynchronous: > > http://www.tweekgeek.com/_e/page/1061/HiFace_USB_Interface_FAQ.htm > > 28) Does the hiFace work in asynchronous mode? > > Sure, the transfer of data over the USB bus happens in a totally > asynchronous fashion, with respect to their retransmission to the DAC, > in short packets which use all the available bus bandwidth. Actually, > hiFace is master in the transmission from PC to interface. As it uses > its low jitter oscillators to time the S/PDIF transmission, line jitter > is totally uncorrelated to data transmission from PC to interface. ...and jitter level should not depend to some degree on the computer itself: > http://www.tweekgeek.com/_e/Portable_Computer_Audio/product/HiFace/M2Tech_HiFace.htm > > Most USB audio interfaces and DACs link the data stream clock to the > same USB interface clock, resulting in very high jitter distortion. > This has prevented the PC from being taken seriously as a high end > audio component. Until now. *The M2Tech hiFace solves this problem by > implementing two quartz precision oscillators as a clock source for the > data stream output*, offering extremely low jitter(e.g. at environmental > temperature stability is 2-5ppm approximately, compared to 50-100ppm > performed by oscillators normally used on commercial CD players). This > results in a more stable clock signal being recovered by the DAC > receiver; resulting in low phase noise, jitter and very little > distortion and signal degradation. Excellent sonic performance is also > reinforced by an internal supply voltage regulation. And yes, this was not posted in order to promote competing product. I'm only surprised how people tend not to bother to do any research or reading, before assuming things so easily. :) And I already posted those links on the previous page. If you wanted to learn if it is asynchronous or not, or dependent to computer's clock over USB, you could just have followed the links and read about it. One more link from the previous page: > > http://www.enjoythemusic.com/magazine/equipment/0210/m2tech_hiface_usb.htm > > *The M2Tech hiFace operates asynchronously with two high precision > clocks covering the multiples of 44.1/88.2/176.4kHz and 48/96/192kHz.* > These clocks have a claimed precision of 2.5 ppm and very low phase > noise. The use of a high performance transmitter allows the output to > have extremely low jitter and M2Tech employs a pulse transformer to > provide galvanic isolation from the computer. But I guess it is easier to assume. :) . -- Kuja ------------------------------------------------------------------------ Kuja's Profile: http://forums.slimdevices.com/member.php?userid=32935 View this thread: http://forums.slimdevices.com/showthread.php?t=80013 _______________________________________________ Touch mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/touch
