SPL Channel One Gate won't switch off

[Rohan white]

So i have a couple of these units. I purchased one recently and the gate on it comes on in quieter passages not too obtrusive when there is background noise or other instruments playing but when recording vocals it can really mess up the take. My other unit which i have had for years just started exhibiting the same behavior after i accidently overloaded it with a feedback loop. Solution is probably just to disconnect the gate entirely but given my basic knowledge this is way out of my ability . I have enclosed the schematic and can do basic soldering, component removal or just cutting traces ( as a last resort) . Can anyone have a quick look at this?

 

[topcat]

So i have a couple of these units. I purchased one recently and the gate on it comes on in quieter passages not too obtrusive when there is background noise or other instruments playing but when recording vocals it can really mess up the take. My other unit which i have had for years just started exhibiting the same behavior after i accidently overloaded it with a feedback loop. Solution is probably just to disconnect the gate entirely but given my basic knowledge this is way out of my ability . I have enclosed the schematic and can do basic soldering, component removal or just cutting traces ( as a last resort) . Can anyone have a quick look at this?

Hi Rohan,

I can only view part of the schematic (the left hand side of each the schematic and pcb pages is missing)...at first glance R116 appears to carry the noise gate signal to the VCA control voltage summer. ..... but this is an educated guess I would like to see the whole schematic before suggesting removing r116...it would be better to repair the circuit

tc

 

[Rohan white]

Heres the full schematic.... sorry it took so long to find and post.

 

[Script]

If you want to fix the unit but don't know how, you could always contact SPL. They speak English alright and have helped me in the past

Contact them not for having the unit serviced by them, but for giving you a hint what might be up with it. .Could well be that yours is not the only unit ever that showed that behaviour.

If you get no usable reply from them, but still want to fix it yourself, you could start with basic troubleshooting. The noise gate circuitry doesn't look awfully crowded with components. But maybe the problem is elsewhere.

 

[topcat]

Totally agree with Script. A quick diy thought, I wonder if the fault goes away when you turn the gate threshold control fully counter clockwise? Could be p6 is duff?

 

[Rohan white]

the gate functions ok but the problem is when you turn it fully counter clockwise it just doesnt switch off as it should, hence it operates in very quiet passages and sometime this means you get a an artifact during the beginning of a word on quiet vocal tracking

 

[mjrippe]

Could be as simple as some dirt in the pot, or a bad solder joint on one leg preventing it from going all the way to ground or V+ or whatever turns it "off".