The Amp Garage

Those are the "right" ones.

If you like 12AX7EH tubes and a 12AT7 (ECCC81) as a phase inverter, I'm guessing that your amp sounds too harsh and a bit uncontrolled without them. If you are using polystyrene-film coupling caps, you might want to change them for polyester-film types. The standard "orange drop" capacitors come in ...

The Moose/Hayboer transformers fit the mounting holes perfectly. The problem is getting the wires from the power transformer inside the chassis, since they originate from only one side of the PT. I cut most of the unused leads (for example, rectifier filaments and low-voltage B+) so that I did not h...

Vaughn, did you use the polyester ODs or the polystyrene (715 or 716) types?

I changed all 12 OD caps on the Climax's board to polyester types. This is worthwhile change as it makes the Lead channel sound very close to my Express clone. See my original post for a few more details.

I don't think Ken Fischer does anything to production units. His Komet came to me with pretty standard tubes, nothing exotic (the unit should have reflected current production, not a tweaked amp for the GP review). It would be a huge logistical expense, a physical drain on Mr. Fischer, and buyers wo...

I know that Fender used shielded cables between the MV pot and the parts board.

Correct, the AC30 does not have feedback. You can choose to select tubes that don't squeal, or you can try to find out whether you are getting some feedback in your wiring layout. Have you determined that you don't have microphonic tubes? If you tap the Tung Sols with no signal input to the amp, do ...

Sometimes the NFB squeal goes away when the presence control is turned way down. My comment was about squealing when first turning on a newly-built amp.

Yes, the high-frequency response and the squealing go together in the Tung Sols. To change the phase of the feedback, you can either (1) swap the (usually blue and brown) plate leads going to the output tubes, or (2) swap the grid leads going to the output tubes (these have 1k5 resistors connecting ...

In making your wiring look neat, you wound up with alot of wires in parallel. I haven't traced them back using a schematic, but I see a potential danger. For some of the high-freq oscillations, it takes only a small amount of capacitance between the "wrong" parts of the circuit. BTW, if you think th...

No, that is not the way to connect a simple MV. The correct way for a simple MV is to: * Connect the 0.1uf cap going to the phase inverter in the original circuit to the "high" terminal of a new 1M-ohm pot (mount this on the front or rear panel). The original 0.1uf cap will now be connected between ...

I never looked inside (out of politeness, since the amp was on loan). I am certain that it was a stock production unit since it was in CA for the Guitar Player Magazine review. It looked like a new Komet.

Don't forget to try a pair of 6V6s -- you'll be surprised at how different they can sound in this amp. It ain't your father's tweed Deluxe.

Terrific!!