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Need advice on potentiometers
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Author:  Radius360 [ 20 Feb 2019, 17:42 ]
Post subject:  Need advice on potentiometers

I have a unit in my car (JL Audio Cleansweep CL441DSP) that converts speaker level signal from the factory head unit to line level output to the amps. This unit also features an aux input to which I connected a wireless bluetooth DAC for my iPhone. A wired remote volume control (potentiometer?) switches between the two inputs via push button.

The high level output from the factory deck sounds like garbage compared to the output from the DAC so I normally leave it switched to the latter. Here is where the problem starts. Either the output on the right channel has increased somehow or the left has decreased. In other words the volume from left / right is no longer balanced. If I touch / move the wire connected to the volume control it sometimes fixes the issue or makes it worse. And sometimes it cuts out completely. My assumption is that this volume control unit needs to be replaced but I have no idea what type of pot I would need in order to switch back and forth between the two inputs.

I’m hoping someone might have a suggestion or can point me in the right direction? Or could this be something proprietary to JL Audio? I can provide more info if needed. I've attached an image showing the main unit and the volume control assembly.

Any help at all would be greatly appreciated! Thanks!

Author:  gofar99 [ 20 Feb 2019, 22:00 ]
Post subject:  Re: Need advice on potentiometers

Hi, Most likely it is a common trim pot (control). It may be just dirty inside and could use something like deoxit to clean it. (do not use WD 40 as it leave a residue). you will need to dissassemble the housing and see exactly what the part is if it is actually bad. It will likely have some markings that will help figure it out. A photo is often helpful. It may be that the control is coming loose on the PCB. A weak solder joint can cause this. We need more information to help you.

Good listening
Bruce

Author:  Radius360 [ 22 Feb 2019, 07:33 ]
Post subject:  Re: Need advice on potentiometers

I was hoping this would be an obvious quick answer but after opening up the parts it might be more complicated. Here are some pics. Looks like maybe a digital pot?

If you tell me this is just more difficult than it's worth I'll take your word for it. lol. I can replace this entire part for about $80

Author:  laurie54 [ 23 Feb 2019, 09:48 ]
Post subject:  Re: Need advice on potentiometers

The board looks like foil is broken on the right hand bottom to top trace. That would sure explain why it goes crazy
when you physically move the wire going to the pot's board. If this is correct you will need a soldering iron to add a
short piece of wire from bottom right solder lug (eg: pin #4), (black wire), to the top right solder lug, (pot pin #3). If the foil
trace next to it is also broken you will need a second wire from that pin, (eg: pin #3) (red wire) to the center pin of the pot (#2)
and you are back in business.

If this is an optical allusion of the pic and the foil traces are not broken, Before buying spray cleaner, remelt
the solder connections on the board at each pin. (do all 9) The problem being intermittent could be a bad solder joint,
again it happens in manufacturing process. Also check that plug interconnect is ok. If this still does not fix the problem
it may be the pot, (i suspect not but it happens), Now try cleaner as suggested. Spray into any opening you can get
it into and rotate the shaft back and forth a few times.

The pot itself, (that is the blue part of the body) is common except for, the extended mounting threads, and
the fact that it has a momentary switch, (the white part of the body) which makes it a custom unit hence the price tag
for a new one. If you need it to go into the same volume/sw box as before then you may be stuck.
But if you could tolerate having a momentary push switch placed beside the pot and you can get around needing the
long threaded mounting shaft then your fix is easy. This pot will fit and solder into the existing board positions.

https://www.digikey.ca/product-detail/e ... ND/3780988
Note the price.
Solder the pot into position on the board as the original. Then solder two wires onto the two switch pads and
solder them to a momentary (N.O.) push switch which would then be mounted beside the pot. A little work and imagination
is necessary but the price and experience is worth the effort. It just depends on how you feel. Your pot is (B = linear taper)
(103 = 10,000 or 10K ohms). The pot, a switch, solder, and a soldering iron would still be less than 1/2 the cost of a replacement unit.

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