Fender Bassman Clone Output Transformer Change and a Few Loose Nuts and Bolts
ฝัง
- เผยแพร่เมื่อ 5 ก.พ. 2025
- We have a very nice Fender Bassman clone. This amp came in for a output transformer change. The one that was fiited when amp was put together was the wrong specs; suitable for 6L6GCs. This amp has 5881s in it. We fit the correct transformer and sort a few other problems. A loose wire on the filaments. And an array of loose nuts and bolts.
- เพลง
I would have thought that any output transformer designed for 6L6GCs would work fine with 5881s, but not vice-versa. That Hammond 1750L is 4.2kOhm primary, 4 ohm secondary with 60W power-handling. Push-pull 5881s can only put out ~45W max. Does he need it to drive a 2 ohm load or something? Mercury Magnetics makes good transformers, but so does.Hammond. Anyway, I guess it’s “yours not to reason why… :-). Great playing in the demo, as usual! Glad that you’ve gotten over your flu bug.
The OT's in the original 6G6 series A, B & C tuxedos were unique to those amps. A BF bassman OT on the outside looks the same, but is wound differently.
The only company making an accurate 6G6 series clone is Mercury Magnetics. (No affiliation).
Hello Jeremy, thank you. I am all good now. The customer wanted the original specs for this amp. As @danh.8490 says
in the comment below, the Mecury Magnetics is the correct spec transformer. I hope you have a great Christmas and a happy new year.
Hello, thank you. Thanks for watching and take care.
As you know, current production Russian 5881 tubes are neither true 5881's or 6L6GCs, but somewhere in between. I use ~25 watts idle plate dissipation as the design maximum when biasing them. There are a couple of good articles by Jay Skylar discussing the variants of 5881's. As another commenter noted, I wouldn't have though it necessary to change the output transformer to run current production 5881's into a 4 ohm load. I have 5881s in a couple of my older Fender amps, and as long as they are properly biased, they work just fine.
Hello Michael. The tubes in the amp were TungSol's. The datasheet says Max dissipation 23 Watts. I biased them at about 16 Watts (70%). There was no crossover distortion on the scope. It's best I follow the datasheets when I am working on customers amps. That bias setting is also right for the transformer. The customer wanted the correct specs for this amp. He says it sounds much better, so all good. It's a good thing he had it changed really. All those loose nuts and bolts wouldn't have held on much longer. I hope you are well. have a great Xmas and a happy new year. Thanks for all the support over the last year. Take care.
Very nice sounding amp, Martyn!
Hello Michael, thank you. take care.
Nice work Martyn.. Very nice sounding amp helped along by your virtuoso guitar playing. There's a few of these Bassman clones knocking around the Rockabilly scene. I suspect that's in large part down to Brian Setzer (Stray Cats) using them.
Hello Pete, thank you. A cheaper way to own one than buying an original one. And no leaky board on this one. Take care Pete.
Room: Green, Guitar: Green, Pick: Green, (Cat: Pink), Playing: White Hot
It looks pretty well built but whoever soldered the chassis grounds needs a hotter soldering iron, or a pair of them.
Is that not a Fender Bassman amp but rather an off brand look alike? If it’s a genuine Fender, what year was it made? I really enjoyed watching you work and subscribed to your channel. About those star nuts, are those the aluminum nuts with the pointy edges around them that go between the hex nut and then dig into the thing they are being tightened against? I’ve seen those taking things apart but didn’t know what they are called. Nice job. 👍☮️🌞🎸🎵
Hello, thank you. Yes , it is a look a like, or clone as they called. Thank you for subscribing. It's great you and so many other support the channel. You are spot on about the star washers. They are must on guitar amplifiers. Thanks for watching and take care.