"Tim Perry" wrote in message
...
i decided to run some measurements on the Behringer mixer i just got then
compare it to some other mixers. here's what i got:
Behringer MX 2642A
% THD
50 Hz .048
100 Hz .05
1000 Hz .05
10 kHz .058
15 kHz .064
IM distortion (60 & 7kHz) .06 %
noise* .0355 mv
Soundcraft F1-16
%THD
50 Hz .048
100 Hz .05
1000 Hz .052
10 kHz .06
15 kHz .068
IM .052 %
noise* .035 mv
Mackie 32-8
%THD
50 Hz .052
100 Hz .058
1000 Hz .05
10 kHz .064
15 kHz .072
IM .06 %
noise* .09 mv
no mixer: straight from sig gen to analyzer
%THD
50 Hz .046
100 Hz .048
1000 Hz .05
10 kHz .056
15 kHz .062
IM .052 %
noise* .014 mv
*methodology:
noise measurements made referenced to -40 dB input and 0 dB output with
sig
gen muted and one ch open all others down.
all other measurement made with 150 ohm source at -40 dB into mic input.
mixer output set to 0 dB into active balanced (transformerless) meter.
tone
controls all at neutral.
in "straight through" measurements the sig gen output was increased by 20
dB.
conclusion: i was rather surprised at how well the 2642 tested relative to
the other units.
the online spec sheet claims a THD of .007% @ +4 dB
i wonder if its an actual measurement or is derived in some fashion.
** Most likely just measued the usual way.
my equipment seems to be functioning within its specified tolerances.
http://www.pi-usa.com/ag51/ag51g.htm#SPECIFICATIONS
** But is not up to modern standards.
Decent audio generators have less than 0.001% THD at 1kHz nowadays.
........... Phil