[sdiy] Insert connectors

[Tony Allgood]

>Unless you want to run into a tape recorder from there....

Use the direct out which all good mixers should have. Although it does
appear to be one of things that is the first to go on the cheaper desks.

But if you want cheap, then have a look at the way Yamaha wire up the
48V feed to the mic/line inputs. Its the usual 6K8 resistor feed, but
switched on one switch across the whole desk. Now each set of four
inputs have their own 48V line connected to the one switch via a 100R
resistor. So if you use >unbalanced< line inputs, those 6K8 resistors
will pass any hot signal to that undecoupled 48V supply line. This then
feeds right into each of the other three channels of the desk just like
really bad crosstalk.

The solutions; individual switching of the channel strip, independently
decoupling every 48V feed to each channel and not in blocks of four, or
to remove the 48 6K8 resistors. I chose to remove the 48 1/8W resistors,
since this was the easiest and I don't use phantom power. Something to
consider if you buy any of the new analogue desks by Yamaha, eg.
GF24-12.

Regards,

Tony Allgood  Penrith, Cumbria, England

Oakley Modular Synth and TB3030:
www.techrepairs.freeserve.co.uk/projects.htm
My music: www.mp3.com/taklamakan