View Single Post
Old 11-08-2010, 05:11 PM   #41
Lawrence
Human being with feelings
 
Join Date: Mar 2007
Posts: 21,551
Default

Quote:
Originally Posted by jnif View Post
Can you show some measurement data where distortion caused by signal below clipping level is shown? And of course in this case the recorded signal has to be a real signal from some mic, instrument or mixing/effect device. Not some unrealistically low or high level signal that has to be amplified or attenuated unrealistically in the pre-amp.
jnif
I don't think it's necessarily speculation. Just look at the specs of some of them on the lower end. It mostly depends on two things... how the preamp is designed, and if it has it's own converter circuit, which of course can be calibrated a little higher, to -15 or so to close that gap to make it less likely.

Some cheap pres will start to clip internally at +14dBu (a good bit below digital 0, the -20 calibration anyway) and others like my M101, not until +26, so I'd be clipping in digital well before the preamp clips. Even then, the warning (clip light) is set at +16.

With some standalone prosumer ASIO devices (pre + converter) I think that may be why they calibrate them a bit higher than the standard pro level of -20, to get the clipping point of the internal electronics closer to digital 0, close that gap... knowing the audience will be much less likely to be informed and thereby leading to better recordings (for that group in general) than calibrating the AD at -20 while the pre is clipping at +14 internally.

Just because home recordists can't always hear the early stages of analog clipping or unwanted distortion doesn't mean it's not happening. It's not as obvious as digital clipping. I suppose you could run sine waves through some cheap pres at -0.01 to a daw to see what happens... see if a particular pre is prone to distortion or clipping at those levels or not.

I do think many, like ART, have generally started to give their prosumer pres lots more internal headroom though. So not a major issue there at least.

Yep's only point was that there's nothing to be gained - only potentially lost - from doing that anyway so it makes no sense either way. But most people doing it (imo, with standalone pres) aren't clipping the pre, they're just gaining up the output.

Last edited by Lawrence; 11-08-2010 at 05:54 PM.
Lawrence is offline   Reply With Quote