Archimago wrote: > For fun, I thought I'd run an old NOS DAC I had lying around to see how > it measures... > > This is the ancient Philips TDA1543 DAC, 4 chips in parallel. This > particular model is the MUSE Audio one you can find on eBay for about > $60 with case, wallwart... > > The DIR9001 digital receiver in this unit allows up to 24/96 but the > TDA1543's are 16-bit chips which will truncate the 24-bit data. Setup: > Touch (WiFi) --> proper coaxial cable --> TDA1543 DAC --> shielded RCA > --> E-MU 0404USB. > > Behold... Stair-stepped NOS output (this is a 16/44 1kHz sine wave > recorded at 24/192): > 14452 > > Summary RightMark results: > 14453 > > 14455 > > Frequency response drops off at the upper end on NOS DAC's at 44kHz > sampling rate and you can see that quite clearly above - this improves > significantly with 96kHz. Looks like the performance overall improves > with 96kHz sample rate in fact. Many folks who use NOS will upsample the > data before feeding into the DAC to take advantage of this fact. > > THD graph (a bit nasty): > 14454 > > Jitter (16/44 Dunn J-Test) - Due to the stair-stepped aliased nature of > the sine waveform, I don't know how much of this is actual jitter: > 14456 > > Well what can one say about NOS DAC's... They measure poorly. Yet, many > swear by them. Sure, this is an inexpensive NOS and there are much more > expensive ones out there like the AudioNote products (the AudioNote DAC > 0.1x looks like it only has a single 1543 and upper models all seem to > use the AD1865 - don't you love their term "1x oversampling"?!). > > Personally, I don't really mind the sound. It does have the high > frequency roll-off which works OK for fatiguing music but that also > takes away some of the "sparkle" in studio productions. Goes to show > just how amazingly tolerant hearing can be! > > Ironically, if many audiophile 'golden ears' can accept that jitter FFT > for NOS DAC's, why quibble about the odd sidebands and whatever > picosecond jitter found in well engineered gear?
Not to quibble when you're bashing "audiophile 'golden ears'" but isn't the jitter in the above graph still well below the audible range? Which kind of means that jitter is really only a selective bogeyman brought out or ignored depending on what piece of gear is being sold. Oops did I just write "sold"? Must have a Freudian slip since I meant "reviewed". So when pushing over priced USB cables jitter becomes this big scary monster and when pedaling badly designed audiophile DACs jitter becomes a cute little harmless kitten. Now hold on because you know it's coming.....THAT'S WHY I CALL THEM CLOWNS!!!!!!!!!!!!!!!! ------------------------------------------------------------------------ ralphpnj's Profile: http://forums.slimdevices.com/member.php?userid=10827 View this thread: http://forums.slimdevices.com/showthread.php?t=97950 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
