Magnatone Project Ideas

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dorrisant
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Magnatone Project Ideas

Post by dorrisant »

Ok... I have a 50's Troubadour here. It is a real mess inside. It has the original PT and I think the OT has been changed at some point, but currently is a Stancor, so I don't see this as a bad thing. The vibrato is not of the pitch shifting variety... too early for that. It is missing the back door, speaker and grill are not original, etc..

So, if I gut and rebuild (g&r) no one should be appalled. That said. I have ideas...

I don't know which preamp I should use. Any suggestions? Be prepared to convince me. :wink:

I want to use some original Magnatone varistors and do the pitch shifting thing. No doubts about that. In addition, I want it to be stereo. In that, I mean that one side would go to a 2x 6V6 power section and on to the contained 12" speaker, while the second side could be used as a preamp out to another amp. This second amp could be whatever is available, really. Also, it could be as far as a guitar cable can reach away from this amp. The Troubadour control panel has a "Remote SPKR" out jack. I thought of using this along with a push-push pot to switch and volume control the output to the remote amp. What do you think?

I like the sound of the current Twilighters, but this is exactly a Deluxe Reverb circuit... Should I go for a more traditional Maggie circuit and if so, which one, space permitting? I can make up a board or do point to point, whichever the space dictates. I will build this. I will also post build pics here too.

All in all, this could be a real sleeper amp.
Last edited by dorrisant on Fri Sep 01, 2023 4:26 am, edited 1 time in total.
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sluckey
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Re: Magnatone Project Ideas

Post by sluckey »

First try to match up what you have to a schematic. Show us some pics of the amp so we can help.
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Re: Magnatone Project Ideas

Post by dorrisant »

Doing this remotely from my new job...

It is a 113 circuit. I will post some pics tomorrow.
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dorrisant
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Re: Magnatone Project Ideas

Post by dorrisant »

Here are some pics of this crusty little rascal...

I wonder how much I should try to preserve. The silk screen is rubbed/scratched off in places but is legible. I'm sure that the face can be cleaned up some as well. This is gonna be all new internally, so I won't be saving a single thing there. I can't see any numbers on the speaker, but it appears to be alnico, so I will have to test it out. Still need to check the PT and OT thoroughly. The PT may have to be changed to fit the needs... maybe not. Lots of things to do here, too numerous to worry about jotting out.

The vinyl covering is not original and will be changed out. Maybe some suede in a color close to what it was wrapped with originally.
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dorrisant
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Re: Magnatone Project Ideas

Post by dorrisant »

A few more...

Also, just for giggles, I'm trying to figure out the decal that was applied to the top of the amp. It seems like one of those rub-on type decals that I used to get when I was a kid. I'm wondering if anyone can recognize the character. I may bring that back into the project for an easter egg of sorts. Seems like the thing to do. Anyone recognize it?

I said I wouldn't use any of it, but I will more than likely reuse the pilot... maybe I'll use the fuse holder too. We'll see.
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Re: Magnatone Project Ideas

Post by Stevem »

No with summer ending ( if you live in this hemisphere) that's a nice Winter project!

Here's some suggestions.

Strip out the chassis and if the control panel is separate then remove it.
Take the chassis to a automotive machine shop that can do glass beading and have them remove all that rust.
Next think about where you might want grounding points in the build up and put screws and nuts thru those holes.

Get a spray can of flat enamel clear like Krylon brand, and coat and seal that now bead basted clean surface.

Let this dry for a full 2 days.

Strip out the control planel and only wash it down with hot dish wash soapy water and a new very soft guitar polishing cloth.
Do not attempt to use any type of spray cleaner out of a bottle, especially Fantastic, as I have had that remove silk screening on me.

Get the panel cleaned up and then give that a coat of the flat clear to protect it.

If you choose not to bead blast the Rusty inside of the chassis then go to a auto parts store a get a brush on or spray on can of rust converter.
This stuff will turn the rust into a primer that stops the rust and then you can top coat it.
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dorrisant
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Re: Magnatone Project Ideas

Post by dorrisant »

Thanks for those suggestions Steve... I'm planning to do all of that.

This post is more about circuit suggestions. Like which Maggie circuit to install along with my crazy ideas.
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sluckey
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Re: Magnatone Project Ideas

Post by sluckey »

Should be easy to build the popular 213 Troubadour in that chassis. Need to add one more tube socket.
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Re: Magnatone Project Ideas

Post by Stevem »

Judging by the basket that speaker looks like a CTS or a Utah.

I have fully removed stickers like that with decal setting solution.

Sometimes it will take 4 or more applications of the stuff along with a scrubbing by a new stiff tooth brush.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!

Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
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dorrisant
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Re: Magnatone Project Ideas

Post by dorrisant »

Steve... I was trying to identify the character so I could use it somewhere on the amp when it is finished. Any ideas on who/what it might be?

Sluckey... I was thinking of using the trem/vibe circuit from the Stereo Twilighter. I'd feed the inboard power section with one side and send the 2nd side as a preamp/line level out.

Maybe I'll just use this schematic and mod the preamp to suit taste. I would eliminate the reverb circuit and add a passive fx loop. Probably use a Deluxe Reverb PT as well.
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dorrisant
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Re: Magnatone Project Ideas

Post by dorrisant »

What is the LFO at the bottom left connected to?
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sluckey
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Re: Magnatone Project Ideas

Post by sluckey »

dorrisant wrote: Sat Sep 02, 2023 3:16 am What is the LFO at the bottom left connected to?
That's the low frequency oscillator. You need a more updated schematic. This will help...
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dorrisant
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Re: Magnatone Project Ideas

Post by dorrisant »

Thanks for that sluckey!

Btw... I think the decal was from one of the Presto Magix or Action Transfers. At least that is what it reminds me of.

https://www.google.com/search?q=Presto+ ... =931&dpr=1

https://www.google.com/search?q=action+ ... =931&dpr=1
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Re: Magnatone Project Ideas

Post by sluckey »

I should have posted the entire schematic. This is for the non-stereo Twilighter but that part of the circuit is the same. No idea why the LFO was not on the stereo schematic.
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Re: Magnatone Project Ideas

Post by dorrisant »

Ok... here is a proposed schematic. A kind of Wonderland preamp thing with the Maggie vibrato. I'm not to sure if the modulation connection is correct since I have a bias balance pot that changes things. I don't have the B+ nodes correctly labeled yet. Let me know if you see any glaring errors.
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