"Jaime Torrico R." schrieb:
>
> Hi Renee:
>
> Would it be to much to ask you to show us some diagrams or just
> drawings of how you did it, please? I love my Gina but lately I'm facing
> the problem of the noise of the fan in the computer, and would like to
> put it a little further that what the cable of the breakout box permits.
O.K. I got rid of two kinds of noises: computer noise AND
electrical interference. This cure only makes sense when your
mixing console has balanced ins and outs for tape.
First I must say: no drawings are needed.
The Gina breakout box is nothing but a 25pin Sub-D socket
soldered to a printed circuit board which holds ten 1/4" sockets.
There's some RFI filtering in the box.
(BTW: I always had contact problems with the 1/4"s)
I stumbled over some old Neumann distribution amplifiers (V482)
which have lots of first class audio transformers.
I made a metal box with a 25pin SubD for the Gina cable
and a multipin connector for the multicore to my mixing desk.
In between I put ten transformers ( 2 in, 8 out). The shield
of the multicore is connected to the console but ends just
before the box. This way I have a balanced audio path but no
way for the interference from the computer back to the
console.
One trick of course is that I paid next to nothing for
ten transformers that normally would cost $60 each.
I did several tests to insure proper audio transmission.
With Cool Edit I made a wav with sine waves in steps of
half octave at -10dB. Then I watched a level meter on
different points of my setup. The performance is within
+/- 1dB so I'm happy with it.
Roll your own!
Renee
--
Renee Rober
Wikingerstraße 4 (demnaechst Hollmannstr. 40)
D-24143 Kiel
