bhaagensen;287072 Wrote: > Like you said cliveb, we've been over this many times. But I do believe > you are wrong in this. From what I know it boils down to this. You > don't loose any resolution until something something like -30dB. > However theoretically you get lower SNR by reducing volume pre-dac > since the DAC introduces constant noise. There's nothing theoretical about it - the SNR certainly does decrease as you increase digital attenuation. But the important question is whether it's a big enough effect to be audible. Given the good noise performance of the Squeezebox DAC to start with, I don't believe it is of any practical significance.
You will note, of course, that analogue attenuation in a preamp results in exactly the same SNR degradation since the power amp introduces constant noise. If you're really anal about noise, you should of course run your DAC at 100% straight into a power amp and control loudness with high-power resistors *after* the power amp. Unfortunately, high-power resistors get warm, which increases their thermal noise, which degrades the system SNR... you can't win :-) [edit: and high power resistors after the power amp also drastically increase the output impedance, which would be pretty catastrophic, so of course they are a no-no. I hope everyone realised I was being flippant] Nobody around here is suggesting that one should use the SB's digital volume control to correct a gain mismatch - you must first get the basic gain staging correct, and only use the digital VC for day-to-day adjustments. All I did was suggest that the OP could try a very simple experiment to see whether it was a solution to his situation. -- cliveb Transporter -> ATC SCM100A ------------------------------------------------------------------------ cliveb's Profile: http://forums.slimdevices.com/member.php?userid=348 View this thread: http://forums.slimdevices.com/showthread.php?t=45736 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/audiophiles
