Arny Krueger ) wrote:
"Brian Takei" wrote in
I'm curious, in the context of feeding a soundcard's input -- how
common is the problem of a preamp/device (especially a +4dBu one)
lacking 'headroom', and for -which- sound cards?

I can hang a number on this. FS for your typical pro sound card input is set
for +4 is generally 10-12 dB above +4. IOW it can take up to +16 to drive a
sound card to FS.,

This roughly corresponds to headroom in analog recorders.

Sound card outputs are more variable as there are some who set levels based
on one of the two poles of the balanced outputs, while others set levels
based on the difference between them. So you might see voltages 6 dB higher
at the output, depending on how you measure that voltage.

Most of the +4 analog hardware in my inventory seems to be able to go there,
and in many cases well beyond. I think that +18 is a low number for maximum
undistorted output, while +22 is not really all that that unusual.


Thanks for the numbers. So, it's not a common problem. That is, it's
much more common for an analog device to be capable of putting out a
clean signal that will clip a digital recorder's input, than the
opposite (i.e. that its maximum undistorted output will -not- reach 0
dBFS, and thus it's unable to use all the bits (which isn't really a
"problem" when tracking, at least where I sit)).

- Brian