SSlmixed.com Forum

Tech discussion => 4K,6K,8K Series => Topic started by: christiancarvin on February 20, 2014, 11:17:23 AM

Title: distortion appears when increasing small fader level **SOLVED**
Post by: christiancarvin on February 20, 2014, 11:17:23 AM
Hello!

This one is tough!
distortion appears when increasing small fader level
I've exchange all the cards one by one and exchange the modules:
in the end it appears that the trouble comes from the module but not from the cards...
Any ideas?
Title: Re: distortion appears when increasing small fader level
Post by: sintech on February 20, 2014, 12:12:13 PM
How are you using the small fader?
Title: Re: distortion appears when increasing small fader level
Post by: christiancarvin on February 20, 2014, 12:16:40 PM
In record mode (Not in vca to monitor)
oscillator from the desk 1kHz in cal. position.
patch: oscillator to tape monitor input
distortion appear at -10 dB on Main Vu.

In this configuration, if I increase any other small fader signal doesn't distort.
Thanks!
Title: Re: distortion appears when increasing small fader level
Post by: sintech on February 20, 2014, 12:18:46 PM
I'd be tempted to build and Audio Probe, you can DIY this easily.

Plugging this into a powered monitor, you can listen to the circuit stage by stage.
Title: Re: distortion appears when increasing small fader level
Post by: sintech on February 20, 2014, 12:23:18 PM
Here's the schematic
Title: Re: distortion appears when increasing small fader level
Post by: christiancarvin on February 20, 2014, 12:33:38 PM
I'm studying this thanks a lot!! ;)
Title: Re: distortion appears when increasing small fader level
Post by: Showcase on February 20, 2014, 08:15:15 PM
Just thinking out loud!

I know on the console I work on I remember having trouble with distortion on a channel which in the end we found out was caused by a bad edge connector (think it was VCA card)
Title: Re: distortion appears when increasing small fader level
Post by: christiancarvin on February 20, 2014, 09:39:10 PM
Thanks show case it can helps!!
Today I went through various cases with distortion:
Oxidation on switches and pots
Old and crackling solders
Group card unscrewed
On my ssl, all the modules have troubles with phase button! Every time you press phase there is a thin distortion that I can decrease a bit with the use of electrical contact cleaner. (I've noticed that it makes the button more harder to push...I'll probably have to use a lub to prevent on damage)

It's a long way...But in the end of the day I played with the desk....And that's so cool!!!
Title: Re: distortion appears when increasing small fader level
Post by: christiancarvin on February 25, 2014, 08:42:34 PM
What lube would you advice me in order to preserve my switches from stucking?
Thanks!