On 14 Apr 2005 19:40:17 -0700, "Mark" wrote:

the DIM 30 test signal as you described it passes through a 30 kHz low
pass filter. Therefore almost any square wave signal generator will
have a suffienctly fast rise and fall time i.e. slew rate for this test
since it will be limited by the 30 kHz LPF anyway.

It's certainly scary that David's tests found so many mic preamps
that performed so poorly. It's just these (un)bandwidth-limited
locations that are at greatest risk of out-of-band overloads.

Mic preamps, D/A summing junctions and phono equalizers are the
unsung Davids in the world of out-of-band Goliaths. Most modern
electronics lives and works behind a wall of low-pass filtering,
so let's all give thanks and appreciation to the front line
soldiers who don't.

And there's another category of "things that get bumped in the
night", the digital LPF. There's lots to be learned about 'em,
but it won't be from me, sadly. They may even exhibit their own
"TIM". And I don't mean Burton. Chomps cigar.

Chris Hornbeck
6x9=42 April 29