The Amp Garage

Just Curious, has anyone figured out the power supply error in the monarch schematic? I'd like to try and build one of these over the holidays. I'm thinking maybe the error is the number of stages connected to each node, or maybe something specific to the reverb version? I built it basically as dra...

Just Curious, has anyone figured out the power supply error in the monarch schematic?
I'd like to try and build one of these over the holidays. I'm thinking maybe the error is the number of stages connected to each node, or maybe something specific to the reverb version?

I bend my components to make a mechanical connection when I do a new build. When replacing parts in an existing build, I don't bother trying to hook them in or anything like that as that would be a major PITA. I haven't had any issues so far!

Lead arrangement/alignment can be very important with this kind of thing. SImply pushing them around while the problem is ocurring with a wooden chopstick can often show you exactly where the problem is. have you also checked that it isn't the instrument cable to be sure? ~Phil I have been chopstic...

Okay so from my experience, even with the amplifier in the chassis, the closer I get the guitar to the amplifier, the higher the chance to induce hum/noise due to the guitar. This only seems to be a serious problem with single coils though, humbuckers seem to avoid it a ton better (thus the name hu...

There’s dozens of permutations of the 5F6A circuit used in JTM45. Exactly what schematic have you used, including PT, OT and choke spec? The OT is an MM Radiospares 045RS-L, the PT is an MM P4550JT-G2M and the Choke is an MAR100C, also by MM. As for the schematic, I've gone with the vintage JTM45 s...

Is the amp bolted down on a steel plate sitting in its cabinet to shield out what sounds to me like 120 HZ buzz that your discribining? Also are the power tubes wired pin 2 to pin 2 and 7 to pin 7? Is the wire coming off each pair of your input jacks sheiled? Thanks for the reply, it's definitely a...

Hi All, I'm currently working on a JTM45 build. When I up crank the bright channel volume, presence and treble and touch or get close to one of the power tubes with my hand while a guitar is plugged in, I'm getting very high pitched oscillations/squealing. This does not happen if I don't plug in a c...

I only solder from the top. When I install the jumper I put just enough solder on the rim of the turret to hold the jumper in place. No solder inside at this time. It's hard to see any solder in that pic, but it's there. Once all the components leads are in the turret I partially fill the turret wi...

Like this... http://sluckeyamps.com/VAC15/underboard_jumper.jpg Sorry to revive this old thread, but I am just curious, when you use this method, do you solder the jumper from both sides of the turret or just the top side? I suppose you don't want to fill the turret completely with solder? At the s...

In case anyone else ever finds themselves wondering about this, I just got the answer from Mojotone today. These transformers have a different stack made with thinner laminations that are a different material than the original. This then allows them to use a larger gauge wire with less turns, while ...

Hi All, I recently got a used Heyboer OT for a Deluxe Reverb. It came from a reliable guy, but the EIA/Model sticker is unfortunately gone. I've tested the ratio with my variac and it seems to have the winding correct ratio for a DR, however, the DCR measurement I'm getting with my DMM on the primar...

Sure why not give it a try. That 27k resistor used to have about 3 mA flowing through it, and now it's more like 4 mA. I think if you reduce the value by 3/4 it will get the voltages back to about the same as they were. 27 x 3/4 = 20.2, so I'd try the 22k. Did the mod, voltages went up but only a l...

Sure why not give it a try. That 27k resistor used to have about 3 mA flowing through it, and now it's more like 4 mA. I think if you reduce the value by 3/4 it will get the voltages back to about the same as they were. 27 x 3/4 = 20.2, so I'd try the 22k. Sweet, I'll be giving that a try tomorrow!...

I believe it is due to the different voltages causing DC current to flow along several paths, including through the 470k LNFB resistor, which is connected to the grid of the mixer stage. Those voltages will change with different tubes, too. Switching the supply node must be reducing the DC current ...