Reverb Pan Noise/Hum?

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Reverb Pan Noise/Hum?

Postby CHEEZOR » 15 Dec 2018, 23:18

I ordered 2 MOD reverb pans to try out in my amp to replace an Accutronics pan. I think I prefer one of the MOD pans, but the noise from both is unacceptable. My reverb had no discernible hum with the Accutronics, but with both MOD pans there is a hum that gets louder as the reverb is turned up. I tried turning it around 180 degrees and didn't notice a change. It is in the bottom of my 2x12 combo, so it is pretty far away from any transformers in the amp. Any thoughts?
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Re: Reverb Pan Noise/Hum?

Postby phatt » 16 Dec 2018, 07:48

If the original pan did not hum then check which end of the original is grounded.
Usually only the *pickup* RCA socket is grounded to the case but not always,, some have the other end grounded.
Phil.

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CHEEZOR (18 Dec 2018, 18:20)
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Re: Reverb Pan Noise/Hum?

Postby CHEEZOR » 18 Dec 2018, 02:55

I just checked and they all have the Output RCA jack grounded to the case. :/

Thanks for the suggestion though!
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Re: Reverb Pan Noise/Hum?

Postby phatt » 18 Dec 2018, 12:59

Well put the old tank back in,, Does the noise go away?

If not then then highly likely the RCA plugs/leads have an internal break, Just by removing them can cause them to fail.
They are a common fail point. If you have a DMM you can check for continuity of the RCA cables.
Phil.

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CHEEZOR (18 Dec 2018, 18:20)
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Re: Reverb Pan Noise/Hum?

Postby CHEEZOR » 18 Dec 2018, 18:24

Yeah, that was the first thing I did. I was like, "I don't remember the reverb being so noisy." So I plugged the original one back in and sure enough, there was little or no noise. Maybe the MOD tanks are just noisier by design? I might try ordering a different Accutronics pan and see how that performs.
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