Aguilar OBP-1SK grounding issue

[Chiliwailer]

I’m an amateur so please go easy on me!

I’ve installed an Aguila OBP-1SK, this is the stack knob version. There is a small issue whereby when I touch the treble and bass knobs I get a kind of grounding noise. I tried grounding the base of the pot, but all it did was make the signal dead.

Has anyone installed this preamp and had a similar issue and if so, what helped please?

 

[Chiliwailer]

Now sorted, but can’t edit title.

 

[mcnach]

Now sorted, but can’t edit title.

what was the solution? if you post it here it may help someone in the future

 

[Chiliwailer]

what was the solution? if you post it here it may help someone in the future

Good point, thanks.

Initially, it wasn’t grounded; I took the wiring diagram literally, but it assumes you’ll ground all pots as basic knowledge - doh!

Then it got tricky…

So, when I grounded it, the output died - turns out that under the bottom row of lugs, there is a bit of metal protruding from the pot base, situated under the centre lug. It was slightly bent, so touching the centre lug, which is output. That meant that the output went to ground when I soldered the ground wire in, causing silence.

 

[mcnach]

Ah, easy mistake to do, and it can be so confusing!

I have had issues a couple of times when I shielded the control cavity with copper tape, and... no sound. You open it, check the wiring, it's all correct, and... it works! ok, put it back in... no sound! All it takes is a little cable strand or a terminal touching the side of the cavity... Glad you found the problem quickly!

 

[Chiliwailer]

Ah, easy mistake to do, and it can be so confusing!

I have had issues a couple of times when I shielded the control cavity with copper tape, and... no sound. You open it, check the wiring, it's all correct, and... it works! ok, put it back in... no sound! All it takes is a little cable strand or a terminal touching the side of the cavity... Glad you found the problem quickly!

…so frustrating! And everytime something similar happens to me I say “this is the last time”… but that’s only until the next time!

Thanks