Line 6 Duoverb Head: Is Everything Glued?

I will start by admitting I was not successful at fixing this amp. I was pretty sure I wouldn't be, and I told my customer that I am not set up to diagnose or repair modeling amps or anything else that is mostly surface mounted components (which are tiny). But I said I'd take a look anyway. I always learn something, and this time was no exception, so I am sharing in case anyone else runs into the same problems I did.

To remove the chassis from the cab, I removed the four usual bolts—one near each corner of the top of the cabinet. The chassis didn't budge, so I removed the four bolts from the handle. That usually isn't necessary, but these handle bolts were indeed attached to the top of the chassis. The chassis still did not budge. There were no other bolts to remove, so after tugging a bit by hand and triple-checking that there were no other bolts, I got a putty knife and gently pried the chassis from the cabinet. That worked, and the reason it was so difficult to remove became apparent when I removed the chassis from the cabinet. In addition to the six bolts, it had been secured with a couple spots of glue.

I ran into a similar problem with the knobs. I didn't want to destroy any pots by pulling too hard on the knob, so I did a quick search to see if Line 6 also puts little dabs of glue on their knobs. I found a lot of forums saying that Line 6 knobs are difficult to get off, but none saying that they were glued, so I tried some pliers and a piece of plastic tubing to protect the finish (see Fig. 1 below). I put the tubing around the narrow part of the knob, gently rocked the knob back and forth a few times then pulled and they all came off with no problem.

Normally, when pot knobs are hard to remove, you would put something on the faceplate to protect it, then use a couple of small screwdrivers—one each side—to pry them off. However, most of these knobs were flush with the surface of the faceplate. I could have just fit a razor blade under them, but that would have damaged the surface.

So if you have the misfortune to work on one of these amps, the chassis does come out and the knobs do come off. Just be careful in both pursuits.