[sdiy] Any idea how Behringer Eurorack volume controls work?

[Don Tillman]

   > From: Tom May <tom at tommay.net>
   > Date: 09 Mar 2003 15:19:08 -0800

   > This is sort of off topic, but if I find the answer I'll learn
   > something new about electronics.  I've been trying to figure out how
   > the volume pots on my Behringer MX802A mixer work.  

I'm unfamiliar with the machine, but it's a great question and
inspired me to make a guess.


Vin
--- R1-----+-------|+ \
           |       |   >---+---- Vout
           |     +-|- /    |
           |     | | /     R2
           |     |         |
           |     +---------+
           |               |
           |               R3
           |               |
	   +----pot--------+
                 |
                 |
                Gnd


The advantage is that large input signals can be attenuated before
they hit an amplifier that might clip them, and small signals can have
gain applied only when needed.  The left side of the pot travel is
attenuation and the right side is gain.

  -- Don

-- 
Don Tillman
Palo Alto, California, USA
don at till.com
http://www.till.com