I'm tired of anemic guitar amps!

[Chuz Life]

I have a neat amp story to share. (I think it's neat, anyway.)

When I was about 10 years old (mid 70's) I was a crossing guard for my school. There was a Bar on the corner of my post which was less than a block from our home. I had an interest in guitar, even at that age and I remember occasionally hearing a guitar being played inside the bar. On hot days, the doors were open.

Anyway, I really locked in on the sound of that guitar and amp.

Fifteen years later or so, I had left for the military and returned, settled down in my own place, decided to invest in guitars and such and decided to shop for a Fender twin reverb.

I found one in the paper. Miles away but a good price. When I went to look at the amp, the guy told me that it belonged to his uncle who played it regularly at the bar on my crossing guard post.

I had to have it!

It's one at the top of my list to refurbish, as soon as possible.

 

[scruffy]

Sounds awesome. But enjoy looking at it at home, because at no gig ever will you be able to use it and get those good tones and breakup. Unless you're a national act who is in charge of the gig, anything over 50 watts can just be left at home. And even most 50W amps will be too loud.

If you keep the amp too quiet to get the good coloration or breakup, then there isnt much point in messing with an all tube amp. Just use solid state or a modeler. It will probably sound better.

This is just my recent experience as a working musician.

Make it 20 or 30 watts. Then you can get those sweet tones without the sound guy unplugging you and without your neighbors calling the cops.

Oh well, we play at the beach a lot. No sound guy, just open air. 100 watts doesn't go very far in open air. It's all about keeping up with the drummer, so we get a balanced sound 50 feet out.

 

[scruffy]

I have a neat amp story to share. (I think it's neat, anyway.)

When I was about 10 years old (mid 70's) I was a crossing guard for my school. There was a Bar on the corner of my post which was less than a block from our home. I had an interest in guitar, even at that age and I remember occasionally hearing a guitar being played inside the bar. On hot days, the doors were open.

Anyway, I really locked in on the sound of that guitar and amp.

Fifteen years later or so, I had left for the military and returned, settled down in my own place, decided to invest in guitars and such and decided to shop for a Fender twin reverb.

I found one in the paper. Miles away but a good price. When I went to look at the amp, the guy told me that it belonged to his uncle who played it regularly at the bar on my crossing guard post.

I had to have it!

It's one at the top of my list to refurbish, as soon as possible.

Cool story.

Silverface Twin?

Master volume pulls out?

 

[Chuz Life]

Cool story.

Silverface Twin?

Master volume pulls out?

Exactly that

 

[Fort Fun Indiana]

Oh well, we play at the beach a lot. No sound guy, just open air. 100 watts doesn't go very far in open air. It's all about keeping up with the drummer, so we get a balanced sound 50 feet out.

I admit, I don't care much for vintage amps. I appreciate the features of modern amps for live gig use.

I plug into an old Fender amp, and I think, "That's a nice sound. When I want just that one sound." And no effects loop.

Im hooked on hybrid digital/tube amps, where I can save as many settings as possible. The Hughes & Kettner has 128 presets. Every dial position is saved, save for master volume.

 

[Chuz Life]

Cool story.

Silverface Twin?

Master volume pulls out?

I have two twins now. (Both silver faced) The one I mentioned above has Pyle speakers. Who knows when they were changed but that amp is much warmer sounding than the other is - with celestion speakers. They are both in rough shape but they work.

I really would like to acquire a Super Reverb some day.

Also, being a curious tech guy, I've plugged my Peavy Sp2s directly into the output a few times on the twin (for outdoor jams) It sounds great in all positions but the bridge. On bridge, it sends nearly all of it to the tweeters. LOL Sounds like ass, when you stand in front of it.

 

[scruffy]

Okay, well, here is the original condition:

"Cap job". lol

 

[scruffy]

Here it is stripped down:

 

[Chuz Life]

Okay, well, here is the original condition:

View attachment 1148537

View attachment 1148539

"Cap job". lol

So only two tubes for the final instead of 4 like the Marshall Schematic showed or are you going to add two?

 

[scruffy]

And here it is with my new PT and OT in place. This is why I chose this particular chassis. 10" from front to back.

 

[Chuz Life]

And here it is with my new PT and OT in place. This is why I chose this particular chassis. 10" from front to back.

View attachment 1148546

Just a word of caution, scruffy, there is a big chance of unwanted magnetic (inductive) coupling that can result from two large transformers being too close to one another.

Just something to look out for.

How close can I place two transformers?

I need to place two of these transformers in a case. How close am I allowed to place them? Can they touch each other (of course, they will be electrically isolated)? Is their orientation with respe...

electronics.stackexchange.com

 

[toobfreak]

Just a word of caution, scruffy, there is a big chance of unwanted magnetic (inductive) coupling that can result from two large transformers being too close to one another.

Just something to look out for.

Well, toroidals have a tightly close-coupled field around them, part of what makes them efficient, and usually you can mitigate any close coupling by orientating the two devices in the right positions.

I'm more concerned about the OT, it is a Canadian company I never heard of. Don't know nothing about them. To me, the gold standard is Acrosound, as the OT is what the speaker load sees and it can make or break a good amp.

The only thing better is to go fully OTL, but that usually requires a very high speaker impedance.

 

[scruffy]

So only two tubes for the final instead of 4 like the Marshall Schematic showed or are you going to add two?

100 watts is sufficient for now.

200 watts would require a considerably larger OT, and there isn't room.

A couple years back I built a 200 watter in one of Mojo's "tall Marshall" cases, it fit but boy was that sucker heavy. I sold it to a guy who swears by it, says he never has to turn it more than halfway up.

 

[scruffy]

Just a word of caution, scruffy, there is a big chance of unwanted magnetic (inductive) coupling that can result from two large transformers being too close to one another.

Just something to look out for.

How close can I place two transformers?

I need to place two of these transformers in a case. How close am I allowed to place them? Can they touch each other (of course, they will be electrically isolated)? Is their orientation with respe...

electronics.stackexchange.com

Yes, that's what the toroid is good for. What little mag there is goes vertical.

You'll notice the master volume and master reverb pots were right behind the PT in the original, didn't seem to matter, the amp sounded pretty clean, no noticeable hum.

 

[Chuz Life]

Well, toroidals have a tightly close-coupled field around them, part of what makes them efficient, and usually you can mitigate any close coupling by orientating the two devices in the right positions.

I'm more concerned about the OT, it is a Canadian company I never heard of. Don't know nothing about them. To me, the gold standard is Acrosound, as the OT is what the speaker load sees and it can make or break a good amp.

The only thing better is to go fully OTL, but that usually requires a very high speaker impedance.

If I'm not mistaken, the plan was to use the Toroidal for the OT. It may not leak much (flux lines) into surrounding component's true. My concern was mor abut the primary power transformer coupling/ leaking 60hz into the OT.

I've never messed with anything direct couples (OTL) or tubes much for that matter. OTL seems like a scary proposition to me! LOL

Edit: Duh, I should have looked closer at the label in your pics.

 

[scruffy]

I'm more concerned about the OT, it is a Canadian company I never heard of.

Hammond?

They're industry standard, just about the only ones that work these days (unless you want to spend 500 bucks on a Mercury Magnetics clone).

Don't know nothing about them. To me, the gold standard is Acrosound, as the OT is what the speaker load sees and it can make or break a good amp.

Yes. This one is an Acrosound clone.

The only thing better is to go fully OTL, but that usually requires a very high speaker impedance.

Yikes. I tried that once, almost burnt the house down.

 

[Chuz Life]

100 watts is sufficient for now.

200 watts would require a considerably larger OT, and there isn't room.

A couple years back I built a 200 watter in one of Mojo's "tall Marshall" cases, it fit but boy was that sucker heavy. I sold it to a guy who swears by it, says he never has to turn it more than halfway up.

Well hell, you've done this shit before. . . . I'll sit back and learn now. I certainly can't speak from experience on a build like this.

 

[scruffy]

If I'm not mistaken, the plan was to is the Toroidal fot the OT. It may not leak much (flux lines) into surrounding component's true. My concern was mor abut the primary power transformer coupling/ leaking 60hz into the OT.

I've never messed with anything direct couples (OTL) or tubes much for that matter. OTL seems like a scary proposition to me! LOL

The toroid is from Antek. Best deal in town, 80 bucks. (It even has a bias tap).

I've never tried a toroidal OT, I wouldn't know where to find one.

 

[toobfreak]

I've never messed with anything direct couples (OTL) or tubes much for that matter. OTL seems like a scary proposition to me! LOL

Do yourself a favor and read up on Julius Futterman. Since then, a few companies have taken the idea even father to design some incredible amps as the OT is the biggest liability in a tube power amp since you are trying to couple a high-Z voltage device to a typically low-Z current device (the speaker).

 

[Chuz Life]

If I'm not mistaken, the plan was to use the Toroidal for the OT. It may not leak much (flux lines) into surrounding component's true. My concern was mor abut the primary power transformer coupling/ leaking 60hz into the OT.

I've never messed with anything direct couples (OTL) or tubes much for that matter. OTL seems like a scary proposition to me! LOL

Do yourself a favor and read up on Julius Futterman. Since then, a few companies have taken the idea even father to design some incredible amps as the OT is the biggest liability in a tube power amp since you are trying to couple a high-Z voltage device to a typically low-Z current device (the speaker).

I might look it up out of curiosity but I'm too old and busy to do much with the info.

Edit: The Julius Futterman OTL Story