17 Oct
2006
17 Oct
'06
7:18 p.m.
Sorry, I'm coming into this late but .....
Dan Mills wrote:
The gain control signal has energy right the way out
to the band limit (and probably aliased around it),
never mind what happens when that hits the multiplier!
You need a low pass filter on the control signal. It should
be somewhere well below 1kHz.
Fixing this right means upsampling and adding a
lowpass filter to the control loop, then downsampling
again.
No it doesn't. You want to absolutely avoid fast changes in
the control signal because fast changes will modulate the
audio signal whcih is **not** desirable.
Erik
--
+-----------------------------------------------------------+
Erik de Castro Lopo
+-----------------------------------------------------------+
"The reasonable man adapts himself to the world; the unreasonable
one persists to adapt the world to himself. Therefore all
progress depends on the unreasonable man."
-- George Bernard Shaw (1856-1950)