Tube Amp Archive

Thank you for helping me again. I really appreciate it. I would have thought the resistance/impedance of the meter would be quite high, at least high enough not to affect the voltage reading. The meter is an early 80’s Fluke 77, it still works so I wouldn’t throw it away. The input impedance of the ...

I have a 5E3 in front of me and I’m a little perplexed at what I’m seeing. I have 212VDC on the plate, I have 14VDV on the grid and 47VDC on the cathode. I have two sources that show that this is quite normal, but it’s not making sense to me, I would think that the voltage on the junction of the 1.5...

Thanks for bringing this up. Unfortunately I’m unable to assist you. Perhaps you may be able to contact Fender and ask them. I imagine at some point they have to offer them as spares as the pots will wear out.

Here is the update on the amp.

Update required due to found error.

The JJ 6V6 is more of a 6L6 in many ways. Voltage wise I have used them in Hiwatt 50 models with well over 470 volts sitting on them. They are capable of higher plate dissipation, but still rated at ~half of 6L6GC rating. Characteristics are very close to 6V6GT. See: https://ampgarage.com/forum/vie...

Also in a cathode resistor biased output stage the voltage seen across the resistor as far as the tube is concerned is subtracted from the plate voltage on the tube. The JJ 6V6 is more of a 6L6 in many ways. Voltage wise I have used them in Hiwatt 50 models with well over 470 volts sitting on them....

sluckey wrote: ↑Thu Oct 02, 2025 4:24 am Lower the screen voltage to bring the current down.

Thanks again for your help, I will give that a try, and see what happens.

sluckey wrote: ↑Thu Oct 02, 2025 4:22 am Lower the screen voltage to bring the current down.

Thanks for your advice I will give it a try and report back.

I have a 5E3 amp to service and it’s one of those amps that is a culmination of mods. (All the parts are of good quality, such as Mercury Magnetics transformers and boutique caps.) It uses a 12AX7 in lieu of the 12AY7, one of the preamp coupling caps is an 0.047uF, the P.I. stage uses the Paul C mod...

I have a 5E3 amp to service and it’s one of those amps that is a culmination of mods. (All the parts are of good quality, such as Mercury Magnetics transformers and boutique caps.) It uses a 12AX7 in lieu of the 12AY7, one of the preamp coupling caps is an 0.047uF, the P.I. stage uses the Paul C mod...

Have you tried cleaning the boards and removing the wax. Lyle Caldwell claims it fixes the issue, though from my experience there was a slight amount of voltage conducting through the board. I had seen his videos & DID try cleaning, then deep cleaning, but no luck. They were really, really caked wi...

Thanks again for your reply and assistance. Much appreciated.

Hi I have a 5E3 clone on the bench and it has the Paul C P.I. mod done to the driver stage. I have heard that the 470K resistor to the input of the triode is recommended (which this amp doesn’t have) but I’m not so sure about the Paul C mod in the amp. I was wondering what the consensus about the P....

On V1 I have 130V and 121V on the plates. However, the DC on the inputs remains even if I take the V1 tube out. So I don't think it's that. Since I posted, I found a similar thread on here where the consensus was that the Mojotone eyelet board conducts(!), and plate voltage creeps across the board ...

Of the attempts I have made with Trainwreck Express/Liverpool amps, I found the amp sounds pretty tight regardless of where the volume control is, the treble seems to get softer at higher volume settings.