DV Mark Little Jazz - Volume Pot Noise

[mozzfret]

My volume pot noise has got to point it is unbearable.( only when i turn it tho)
Has anyone experience in repairing this and getting a replacement part they would be kind enough to share?
I thought I saw a post about this before and i apologise in advance if this is the case but despite many searches I cannot locate it.
This was the connect pot before it got professionally re soldered.it did NOT fix the problem but its shows the shoddy manufacturing.

[sgosnell]

I haven't heard of this before. My only suggestion, without tearing into the amp, would be to vigorously twist the volume control, repeatedly, to see if that cleans things up a bit. Sometimes pots just get some corrosion built up, and the wiper can burnish it. I've done that many times with many pots, but not on the Little Jazz.

[rpjazzguitar]

Could possibly be subtle cracks in the solder connecting the pot to the board.

Might be worth reheating the joints and testing it before replacing the pot.

It's easy to do if you can expose that part of the board.

[Eck]

Could possibly be subtle cracks in the solder connecting the pot to the board.

Might be worth reheating the joints and testing it before replacing the pot.

It's easy to do if you can expose that part of the board.

Spot on! It’s hard to imagine a rusted pot on such a young amp. In general I like electric shaver spray for rusted pots.


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[PatrickB]

Does the pot sound scratchy (vs. noisy) when you turn it? Deoxit spray might work.

quickly-fix-scratchy-sounding-amplifier-knobs

[mozzfret]

Thanks for replies people!.
I tried twisting it hundreds of times and spraying contact cleaner into pot, no change so I eventually took to tech repair who redid the solder but the fault is still there!
so now trying to investigate replacing the volume pot.
There is no noise unless you play a note then twist the pot while note sounding. then it makes dreadful crackle whenever adjust volume while playing which makes amp a pain to adjust volume when performing or setting up. But once you have set the volume there is no more crackle.
edit: I just noticed the pot shaft is kind of loose in the housing(?) and I can wiggle it side to side, maybe this is cause of crackle/scratchy problem. Also the noise is much worse between the 0 and 1 marks on the dial.

[Eck]

Thanks for replies people!.
I tried twisting it hundreds of times and spraying contact cleaner into pot, no change so I eventually took to tech repair who redid the solder but the fault is still there!
so now trying to investigate replacing the volume pot.
There is no noise unless you play a note then twist the pot while note sounding. then it makes dreadful crackle whenever adjust volume while playing which makes amp a pain to adjust volume when performing or setting up. But once you have set the volume there is no more crackle.

So it only crackles when it’s making sound, but not when there is no input?


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[rpjazzguitar]

So it only crackles when it’s making sound, but not when there is no input?
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Sounds like a noise gate, somehow.

[mozzfret]

So it only crackles when it’s making sound, but not when there is no input?


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that's right no crackle if turn shaft with no input.

[Gabor]

On my DV Mark 12 (which has literally the very same amp module) it was always noisy from the begining. I think contact spray colud solve this, but I has no such a thing... :-)

[Eck]

I’m quite puzzled! I start thinking it is the class D power section. Just one big chip and not too expensive to buy but you’d have to find it input points and feed it with a varying signal from another preamp and to be safe use one that runs on a battery to avoid massive earth issues. If it’s volume it would be the last thing before that unit (apart from a coupling capacitor) unless.... it could be buffered with a jfet or an opamp and a jfet can be broken or it’s power supply badly connected. It gets complicated.


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[KirkP]

Based on your description it seems clear it’s a dirty or bad potentiometer. If Deoxit D5 contact cleaner didn’t do the trick, you might try Deoxit F5 fader cleaner. It includes a lubricant that might be better for the resistive strip in the pot.
DeoxIT(R) Fader, #F5S-H6

However, if the shaft is very loose I wonder if it’s causing the pot to totally lose it’s connection. I don’t know how you’d correct that without replacing with a new pot. Youtube has a few videos on potentiometer repair, so you might see if they can help. Here’s one where he basically does surgery on it.