My Twin is fixed. (Pics incl.)

[Joel66]

Hi y'all. I was out yesterday checking out Marshall's and ran into a '74 Twin that sounded fantastic and was, I thought, a steal. I bought it.

I got it home, and after playing through it with the volume around 4 for about 5 mins or so, it made a kind of "farting" sound and then the volume dropped drastically. I changed all the pre-amp tubes with some spares that I had here (some NOS RCA's and a couple of tubes that I took out of another amp). No change.

I tried it this morning and it sounded great for a couple of mins., then the same thing happened.

Any ideas if there's something a novice could try? I don't know if the local guy is in the shop today, and I'd really like to use it tomorrow night if I can.

Thank you in advance,
Joel

[trag-o-caster]

Hey Joel!

Congrats on the amp score. Sorry that it didn't turn out quite so well, but I'm sure that it'll be a cheap fix if you have to take it in.

I'm NOT an amp tech, so I hesitate to answer, but if it were me - I'd try some other output tubes in there and see if that fixes it.

Then again, someone more knowledgable than myself may tell you "Shut it off and don't turn it on again until you get it to a tech".

Anytime you buy one of these things nowdays, you should plan on having them looked over before taking them out to play. A buddy just bought a 73 SFDR and was going to just take it out on his job. I talked him into having it looked over, and good thing that we did. It was biased about twice as hot as it was supposed to be, making for a cool fat tone - and a MUCHO quicker tube death rate.

Good luck to you my friend! I'm sure all will turn out well.

[Joel66]

Originally Posted by trag-o-caster

Hey Joel!

Congrats on the amp score. Sorry that it didn't turn out quite so well, but I'm sure that it'll be a cheap fix if you have to take it in.

I'm NOT an amp tech, so I hesitate to answer, but if it were me - I'd try some other output tubes in there and see if that fixes it.

Then again, someone more knowledgable than myself may tell you "Shut it off and don't turn it on again until you get it to a tech".

Anytime you buy one of these things nowdays, you should plan on having them looked over before taking them out to play. A buddy just bought a 73 SFDR and was going to just take it out on his job. I talked him into having it looked over, and good thing that we did. It was biased about twice as hot as it was supposed to be, making for a cool fat tone - and a MUCHO quicker tube death rate.

Good luck to you my friend! I'm sure all will turn out well.

Thanks Tim. I thought about swapping out the power tubes, but unfortunately I don't have any extras. (I know, I know, always keep spares on hand ) I'm going to call the guy that worked on my Blues Deville when they open. (another hour.....now's when I need more patience . I don't wait well)

Joel

[Joel66]

the tab that's attached to the speaker (where the wires connect to the spk) is broke and the wire that attaches to the back of the tab is off. I'm going to check around today and see if I can find a new speaker.

Joel

[Stan Martin]

those speakers are probably fine, however I wouldn't keep running the twin with an intermittent speaker load. bad bad for tranny.

[Joel66]

Originally Posted by Stan Martin

those speakers are probably fine, however I wouldn't keep running the twin with an intermittent speaker load. bad bad for tranny.

I tried to resolder it. I can't solder worth #@!#. I'm taking the amp to someone else and see if he can fix it. If he can't then I'll may pick up a pair of speakers from him. I will, however, keep the speakers that are in it and see if I can't get it fixed sometime.

Joel

[Joel66]

I took it to a local store and the guy there soldered it. It was much easier to do with another set of hands to help. I'm probably going to sell it though.....I think.....maybe. It sounds great, not as good as it did at the store I bought it, but nothing ever does. (The store, by the way, is in a really old downtown store front. Ceiling is probably 15 feet or more, hardwood floor, and the amps face a brick wall about 20 feet away. Great room reverb.)

A little more about the amp. Going by the transformer codes (the tube chart is partially torn off), dates it as 1974. Cosmetically it's kind of rough, though I have seen worse for $550 and more. Normal channel has a broken bass knob (no problem), and the mid pot shaft is broken (a little more of a problem). Vibrato channel is missing the reverb knob. Master vol. pot needs to be changed. It works but the shaft will pull out of the pot. The speaker baffle has been replaced and the grill cloth has some tears. A couple of small tears in the tolex here and there. Reberb and tremelo work great although it is missing the footswitch. I'll post some pics of it shortly if I can.

Any how, I just wanted to let y'all know that it was fixed.

Joel

[Joel66]