Replacing pot in an amp

Sep 23, 2005 at 4:55 AM Thread Starter Post #1 of 5

htbyron

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OK, I'm taking a deep breath before I dive into this forum. I've never been handy (think all thumbs), so I never contemplated a DIY project. But I picked up an amp (the Little Dot II tube amp), and the pot seems to me imbalanced. One recommendation is to just change out the pot. That's a somewhat appealing prospect, as I can imagine I might get a benefit from it. (I also hate the lightweight plasticky-feeling volume control knob, so I could kill two birds with one stone I suppose.) So my question is -- how hard would this project be for someone who has never done any DIY electronics before. I have somewhere in the garage a real cheap soldering iron, although I can't recall if I ever used it successfully (I'm guessing not, as I probably bought it when I was planning to repair something & eventually just gave up). But I may be game for a challenge, so I'm open to being encouraged (or discouraged for that matter, which could happen here or in the middle of the project, I imagine). Any thoughts?

Thanks,
Tom
 
Sep 23, 2005 at 5:37 AM Post #2 of 5
Tom, yes you would be in for a mild challenge.
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The pot on the LDII is board mounted, and to get at the underneath of the board you will have to remove the LED and hope there is enough give that you can tilt the board up and have enough clearance to get at the bugger with an iron, otherwise you'll have to desolder the RCAs and IEC socket too. You would then run solder wires in place of where the board mounted pot was and run them to a new pot. A new hole may also be needed as there might not be enough clearance for it using the existing hole. After I considered all this I decided I'd leave mine alone.
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Replacing the knob is a piece of cake though, so you can at least do that.
 
Sep 23, 2005 at 5:59 AM Post #3 of 5
If you do this by removing parts as described, it is indeed probably pretty difficult. However, from the board layout
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it appears that the input goes straight to the pot, to a couple of caps, and into the tube. You can thus probably simply clip the pot off the board and replace it with an off board pot without the need to desolder anything. You would then need to run some wires from the input to the pot and from the pot to the caps. This is still not easy (particularly in light of the fact that the new pot will likely be too large and will need a new chassis hole drilled for it) so you should find someone with some experience to help, but it can be done. There is a reason people who like to tinker like point to point wiring.
 
Sep 23, 2005 at 4:26 PM Post #4 of 5
Thanks for your help, guys. Given how little of that I understood, I think I've just confirmed that I got no business in this forum.
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Seriously, it looks like too much for me to attempt. I will continue to evaluate how bad the channel imbalance is, then get in touch with the manufacturer about it. If I can live with it, maybe I'll just replace the volume knob with something sturdier. Any recommendations/advice on that (hopefully simple enough) project?

Thanks,
Tom
 

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