[LAU] [Music] Sans titre - Without title

jonetsu at teksavvy.com jonetsu at teksavvy.com
Thu Aug 25 01:16:05 UTC 2016

On Sun, 17 Jul 2016 19:45:47 -0700 (PDT)
Len Ovens <len at ovenwerks.net> wrote:

> The more likely thing is that the clipping is happening in the analog 
> ciruitry before the ADC. All of these cards take their voltages from
> PCI (+/- 12v - ish) That has to be dropped a bit to get anything like
> DC voltages through regulation. A +4 input does not peak at +4 but
> might peak as high as +27dBu (for the MPAII in question) which is
> about 50 v p-p... I would call that clipped with no pad in front of
> the gain stage.
Since then I got an ART Pro MPA II.  Still getting (or starting to) with
it. That device by itself makes noise, I find.  First of all, there is
a choice of +4db or -10dB I/O levels.  Going through the 10101LT user
guide, and assuming that the switches are at default (did not took the
card out of the computer) which is -10db, the output of the MPA is then
set at -10dB.

Since the device itself makes noise, then the gain has to be brought
loud enough to go over that noise, so that at room sound takes
over, eg. room is made for the instrument.  Using only one mic so far
(AT2050 in cardiod mode) it is not possible to make the VU meter
needles move with the playing but, the sound gets to Ardour all right.

Since this is very early, I have certainly no conclusions thus far.


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