filter cap question

[nosaj]

It looks pretty much like those photos, maybe not as neat. Personal preference I suppose, I don't mean to put down his amps, but my initial reaction was underwhelmed. Silver solder and telfon wire don't really move me for a tried and true imperfect circuit as much as solid construction, but that is me I suppose. There are thousands of great Fenders out there without magic parts. I suspect this amp is prone to oscillation based on when I was checking the speaker jack I plugged in a dummy input jack just to create some sound, and I found the volume of the noise floor changed drastically depending where my hands were, as in DECREASING quite a bit. as well as squealing when I placed them in other areas. I didn't probe for it though. It is interesting though that he builds with the stock iron from the reissues.

Running the chassis without a cab and expecting that seems similar to running an old car without the air filter and noticing how your hand affects it when you use your hand to cover part of the carburetor.
It's a lot easier to pick apart others work, but one thing he does have is name recognition and people like what they get Not a whole lot you can say about that.

nosaj

[bob p]

It looks pretty much like those photos, maybe not as neat. Personal preference I suppose, I don't mean to put down his amps, but my initial reaction was underwhelmed. Silver solder and telfon wire don't really move me for a tried and true imperfect circuit as much as solid construction, but that is me I suppose.

I posted the porn photos of the Alessandro DRRI rebuild because I thought you'd benefit from studying them if you're going to offer a DRRI rebuild service using boards. They should also provide you with a standard for comparison for the Alessendro-wired amp that's come in with problems. On the amp that's come in for service I was thinking that you could compare the photos to the UUT to see if anyone has changed anything. On your future rebuilds, the photos show what I think is an excellent benchmark for AB763 lead dress. The photos are worth studying, as it's easy to miss a lot of the subtlety unless you look at the lead dress carefully.

I think the lead dress actually looks quite good and there's a lot that can be learned from it. If you look closely at the wiring, the lead dress is not at all sloppy. He used solid core wire so that it would stay bent where he bent it. The wire shapes may look odd, but there's method to the madness -- he bent each of the leads so that the crossovers with other leads would be as close to 90* as possible. His lead dress looks far more professional to me than what you'd find in a typical Fender amp that has stranded core wire that will not stay where you put it..

The teflon wires do look very thin, and perhaps that could lend to the illusion of lack of solid construction to someone who doesn't routinely use teflon wire, but don't be misled by appearance. Teflon wire insulation is much thinner than PVC insulation because it doesn't have to be as thick to accomplish the same goal. The signal wires are likely to be the same gauge as used in a Fender, though they appear "dainty" because the thinner teflon insulation makes the wire appear thinner.

All things considered, I think his wiring methods are excellent. I don't have any interest in buying one of his amps, as I don't subscribe to the silver solder mojo, though I do use teflon wire. It's more difficult to work with than PVC. Looking at those photos I think he does good work and the people who buy his rebuilt amps are getting professional conversion work done -- the quality appears far more professional than the work performed by the average amp guy. Personally I wouldn't pay the price for one of his upgrades, but if I were a guy who was going to throw down several $100 bills to get conversion work done, I couldn't imagine anyone doing better work. I think his wiring methods are a good reference for someone who is doing a DR build, and an even better reference for someone who is offering a DRRI reissue rebuild service. I hope that you find them helpful. I would study them closely.

[bob p]

I suspect this amp is prone to oscillation based on when I was checking the speaker jack I plugged in a dummy input jack just to create some sound, and I found the volume of the noise floor changed drastically depending where my hands were, as in DECREASING quite a bit. as well as squealing when I placed them in other areas. I didn't probe for it though.

I'm not sure what you mean by "a dummy jack to create some sound," but if your intent is to pickup ambient noise at the input you could be successful in doing that with an empty jack. Plugging an empty jack into the chassis and moving your hand around the interior of the amp with the Faraday shield removed is not a particularly helpful test.

I liked the carb analogy -- I wouldn't bother worrying about using your body as an antenna to introduce noise into an open amp. The real test is whether the amp is going to be noisy when it's buttoned-up with the Faraday shield in place.

The way that you described moving your hands reminds me of someone playing a theremin!