Tube amps!!!!

[Deleted]

Hey all. Well, since I don't have my shop anymore. I needed to have yet another hobby. So I have really gotten into working on tube amps. Mostly Fender and Peavey.
The other day I had a guy call me up and asked me If I would be interested in a Fender Hot Rod Deville. He wanted to do some trading. So I thought sure why not. So it's USA Deville with the 2 12's in it. He told me he just did not like the amp. It's too lowed and is making noise, that he said no one has been able to fix.
So I would up trading my EPI Gold top guitar for the amp. The next day I did some looking around on line to see if I could find out why this amp was so noisy. So I took the back off to see the maybe the filter caps were bad. Just by looking at them they seemed to be good. So the next thing I looked at were the tubes. Hum...
Someone replaced the power tubes and it looked like someone had put in new 12AX7 in it as well. I just happened to have a few set of the 12AX7's So I replaced them and bam!!
NO more loud noise. So today I got me a new multi meter, so I came home and check to see where the bias, and it was way off. The bias needs to be around 60, and it was over 80. No wonder the amp was nit sounding good.
Now on these amps the reverb is supper touchy. They really don't sound all that good. Well, as it turns out there is a simple fix for that. There is a small transistor for the reverb, and all you do is cut one leg into. Now the reverb sounds awesome! Full and rich like a twin reverb and now I can control the reverb much better.
In a few weeks I am going to up grade the inputs, and change out the master volume control. That is the other problem on these amps. I will also be doing a mod that will let the master volume become just that a master volume for the whole amp. Right now the master only controls the lead side of the amp. While I am at it, I will be testing the filter caps,and may change them out to a better caps. But as of now the amp sounds really good!!! It's quit even with a guitar plugged in. Well, anyway just thought I would share what I have been up to.
EB

[antares]

Was it the power tubes that needed biasing? I never bother with 12AX7s, I don't believe that those preamp bottles need biasing?
It's good to hear that you're keeping your hand in Eddie.

[Deleted]

Apr 2, 2017 6:56:23 GMT -6 antares said:

Was it the power tubes that needed biasing? I never bother with 12AX7s, I don't believe that those preamp bottles need biasing?
It's good to hear that you're keeping your hand in Eddie.

Yes the power tubes. It's an easy thing to do in these type of amps. But I did replace the preamp tubes with some I had on hand. One of the tubes that were in it, was making all kind of noise. Plus with the power tubes being so far out of bias, they were making a hiss sound. Way over heating the tubes. I was surprised that the power tubes were OK. Hard telling how long the last owner used this amp with the over clocked bias. Also surprised that nothing was burned up in the amp.

Played on it for a while today, and the amp just keeps sounding better. I really want to do the mast volume mod to it. But it will have to wait for another 2 or 3 weeks.

My Mom passed away Feb 25. I just now got all the paper work in order so I can take her to be with my dad. So the wife and I will be gone for 2 weeks.
I'll order the parts I need for the amp, sometime after I'm back home.

EB

[dnic]

Sounds cool Eddie, good to keep busy.

[antares]

That's real sad news Eddie. I lost my mum when I was 14 so I know how it feels to lose a mom, but of course I don't know how you must feel. I hope all goes well with your plans. We're all thinking of you.

[GuitarAttack Forum]

Sorry to hear about your Mother, Eddie. Let us know how it goes.

John

[Deleted]

Apr 3, 2017 14:00:52 GMT -6 GuitarAttack Forum said:

Sorry to hear about your Mother, Eddie. Let us know how it goes.

John

Sure will John. We will be going to FL soon. To put her with my Dad.
EB

[Deleted]

OK... I ordered the parts I need for this amp project. They should be here this week. If you all are interested, I can take some pictures and post them.
This should be a fun amp project.
EB

[dnic]

That would be interesting I know nothing about amps.

[Deleted]

Apr 17, 2017 17:44:49 GMT -6 dnic said:

That would be interesting I know nothing about amps.

I have been learning a little at a time. I buy tube amps, (most of time) that are need of fixing. I can get them for next to nothing, because they are not working at all or sound really bad.
Most of the time it's bad solder spots on the tube sockets or in other places. So far I have been able to fix all the amps. I think this one is like number 10.

Like guitar repair places here the amp tech's here like to rip people off. I got hold of one amp not too long ago that was taken to one of the amp tech's here in town. I was told he had replaced the tubes and did some other work to it. No so, when I got the amp, it had a broken tube and no other work was done to the amp. But because the amp was kind of working with the broken tube in it, that guy charged the guy who owned the amp a 150 dollars, and did nothing to the amp.

So this is why I wanted to learn how to work on amps. I stay with Peavey and Fender amps because they are easy to fix and easy to work on. Some other amps like Masa Boggy, and VHT get a little more involved.

My parts for this project won't be here fro a few more days. The seller did not send the parts off when he said he did. But they are on the way now.
I hope to get started on this amp, this weekend. Been having some bad problems with my hands shacking, so I'll see how things go.

EB