Anybody here fix up an old radio and convert it to a guitar amp?

[Leonardocoate]

So page three and we still do not know what tubes are in the radio. Does that mean you will not be using the tubes or the output transformer?

nothing looks usable to me and if it is I am not the guy to restore it. My original post was mostly out of curiosity. I am more inclined to buy a 5w Mono price and retro fit it.....I am mostly blown away by the wood working in some of those old radios

 

[TokyoPortrait]

Hi.

This might not have happened, according to the ‘pics or it didn’t’ rule, but once I went to an antique store, just looking around. Noticed there were several old radios converted to guitar amps. Quite cool.

Also noticed several guitars hanging on the wall in the back room. Got to talking. Turns out the owner also deals in guitars. He bought out a Telecaster Jeff Beck had given him (& had the ‘pics or it didn’t happen’ proof). And an old Gibson arch top he’d sourced for Eric Clapton, but at that stage was unable to deliver, due to the unmentionable thing.

Turns out his childhood friend is one of Japan’s main concert promoters, so he gets back stage passes to all the huge superstar shows and has made a bunch of contacts that way.

All of which is to say, yes, it would be worth the effort.

Edit: or, not worth it, if you don't know how to make it into something that won’t kill you.

Pax/
Dean

 

[mfguitar]

I have no idea what I am doing but I did convert an old phonograph, much closer to a guitar amp. It pretty much works as is, I have the box that looks pretty cool but the amp has never made it back into the box. I like the looks of the tubes glowing

 

[Leonardocoate]

Hi.

This might not have happened, according to the ‘pics or it didn’t’ rule, but once I went to an antique store, just looking around. Noticed there were several old radios converted to guitar amps. Quite cool.

Also noticed several guitars hanging on the wall in the back room. Got to talking. Turns out the owner also deals in guitars. He bought out a Telecaster Jeff Beck had given him (& had the ‘pics or it didn’t happen’ proof). And an old Gibson arch top he’d sourced for Eric Clapton, but at that stage was unable to deliver, due to the unmentionable thing.

Turns out his childhood friend is one of Japan’s main concert promoters, so he gets back stage passes to all the huge superstar shows and has made a bunch of contacts that way.

All of which is to say, yes, it would be worth the effort.

Pax/
Dean

No cool story in my OP. To your point, when you are out there doing stuff anything can happen.

 

[Lowerleftcoast]

I found this Philco cabinet and put in a 5E3 chassis. Does that count?

 

[Leonardocoate]

I have no idea what I am doing but I did convert an old phonograph, much closer to a guitar amp. It pretty much works as is, I have the box that looks pretty cool but the amp has never made it back into the box. I like the looks of the tubes glowing

like a camp fire

 

[Leonardocoate]

View attachment 1087548

View attachment 1087549

I found this Philco cabinet and put in a 5E3 chassis. Does that count?

That looks awesome! Yes it counts...Retro fitting an amp into one of these historical gems seems to be the most practical choice

 

[58Bassman]

The power transformer primary coil would not be directly connected to the chassis. If it was, it would be with what we call the Death Capacitor. Radios with no transformer would have the chassis hooked up to one side of the plug but they got away with it by having the radio enclosed in wood or plastic with wood or plastic knobs.

You're right, but not all were transformerless. The amp in the photo is the Oahu I wrote about, made around 1937, and a lot of radios weren't very different from these amplifiers.

 

[printer2]

You're right, but not all were transformerless. The amp in the photo is the Oahu I wrote about, made around 1937, and a lot of radios weren't very different from these amplifiers.

My first sentence said "The power transformer primary coil would not be directly connected to the chassis." which does imply using a power transformer. I am quite familiar with radio construction at the time. Guitar amplifiers used the same circuits as radios back in the day.

 

[Peegoo]

If you're considering re-wickering an existing circuit, here's a pretty good primer on the topic.

Read through the entire thing--even if the sections that you think will not apply to your specific starting point. It's all very instructive, and it will prevent you from making mistakes.

Converting Integrated/PA Tube Amps into Guitar Amps.

www.rru.com

 

[Bill Moore]

I was over at my daughter's place in T or C last week, and noticed a CL add for an old upright radio. I looked at it, and brought it home for $20. It was 40's-50's, has an input for television, and phonograph, 6F6 output tubes, and maybe a 12" field coil speaker. I gave it to my brother in law who has a couple others in his house. Wish I had taken a pic, it looks pretty cool, and would probably be an easy 5E3 conversion, also be cool to figure a way to utilize the "magic eye" tuning indicator!
The guy told me it weighed 84# so gigging with it would be a chore, although maybe most of the weight was in the huge "magic loop" antenna which took up half the space next to the speaker.

 

[Jeru]

OH YEAH.

 

[printer2]

I was going to run a preamp into the phono jack but may just get rid of it as I will have enough amps around.

This one has a tilt out radio, turntable under a lid on the top. I want to convert this into a cabinet with drawers. It is missing the field coil 12" and has a pair of 6F6 output tubes which can do 10-20W. I think I have six 6F6's from this one and two other radios I stripped.

Tabletop radio, not working.

Pretty clean.

Just the cabinet.

Other than a chip in the left, back corner this one looks and sounds like new. I can not bring myself to hurt it. $10.

 

[Leonardocoate]

I was over at my daughter's place in T or C last week, and noticed a CL add for an old upright radio. I looked at it, and brought it home for $20. It was 40's-50's, has an input for television, and phonograph, 6F6 output tubes, and maybe a 12" field coil speaker. I gave it to my brother in law who has a couple others in his house. Wish I had taken a pic, it looks pretty cool, and would probably be an easy 5E3 conversion, also be cool to figure a way to utilize the "magic eye" tuning indicator!
The guy told me it weighed 84# so gigging with it would be a chore, although maybe most of the weight was in the huge "magic loop" antenna which took up half the space next to the speaker.

Too bad you don't have a pic....I'm not sure they are gig worthy but more as a piece of furniture/practice amp...I love the aesthetics

 

[Leonardocoate]

I was going to run a preamp into the phono jack but may just get rid of it as I will have enough amps around.

This one has a tilt out radio, turntable under a lid on the top. I want to convert this into a cabinet with drawers. It is missing the field coil 12" and has a pair of 6F6 output tubes which can do 10-20W. I think I have six 6F6's from this one and two other radios I stripped.

Tabletop radio, not working.

Pretty clean.

Just the cabinet.

Other than a chip in the left, back corner this one looks and sounds like new. I can not bring myself to hurt it. $10.

Pretty cool. The last one shown could be a cool desk top practice amp

 

[jkingma]

I saw a bunch of old antique radios fixed up real nice and then remembered that I have one in my basement. I wonder if it would be worth the effort to fix it up. Here are some pics of what I saw and what I have

A friend of mine builds all sorts of low watt tube amps from old electrical stuff. I've got 15 watt and a 2 watt amp that he built.

Here are a couple of his latest creations. I don't have any photos handy of mine.

 

[Greenmachine]

Hmm four pages in and no one's mentioned the most famous radio circuit conversion of all: The Deacy Amp as used by Brian May of Queen.

For your reading pleasure:

The story of Brian May’s Deacy amp, the little amp that could

We trace the lineage of Brian May’s legendary Deacy amp, integral to Queen’s huge studio tone.

guitar.com

 

[Leonardocoate]

A friend of mine builds all sorts of low watt tube amps from old electrical stuff. I've got 15 watt and a 2 watt amp that he built.

Here are a couple of his latest creations. I don't have any photos handy of mine.

View attachment 1088003
View attachment 1088004

wow! Those are cool. Looks like old lunch boxes

 

[Leonardocoate]

Hmm four pages in and no one's mentioned the most famous radio circuit conversion of all: The Deacy Amp as used by Brian May of Queen.

For your reading pleasure:

The story of Brian May’s Deacy amp, the little amp that could

We trace the lineage of Brian May’s legendary Deacy amp, integral to Queen’s huge studio tone.

guitar.com

Great story! I never heard that before. I know the old radios where tube driven but I'm thinking about retro fitting an old Frontman that I have into my cabinet.

 

[58Bassman]

A friend of mine builds all sorts of low watt tube amps from old electrical stuff. I've got 15 watt and a 2 watt amp that he built.

Here are a couple of his latest creations. I don't have any photos handy of mine.

View attachment 1088003
View attachment 1088004

Those and others like them are very cool AND useful. I bought a Stromberg-Carlson AU-33 when the stereo store I had worked for was closing and everything was half off. The service tech at that place had absolutely zero imagination and didn't give a rat's butt about much of anything other than himself, so he soldered a piece of speaker wire to the 8 Ohm tap & ground, then passed it through an opening and cut it about 4" long, so it would be easy to connect to a regular speaker- it originally had octal sockets for the speaker connections. It could be used with 4,8 or 16 Ohm speakers, as well as 25V, 50V, 70V or 100V speaker systems for public address, AKA 'fixed voltage audio systems'.

I wanted to use it for guitar, so I removed the octal sockets, cut the wires off and put heat shrink tubing on all of the speaker wires except the 4,8 and 16 Ohm. I cut a piece from a Stainless steel wall plate for the 1/4" jacks that replaced the octals- one was for the speaker, the other for the Marshall Style impedance selector. It originally had three Amphenol 1/2" mic connections which are generally obsolete, so I replaced two of them with 1/4" jacks, which dropped right in. I kept the third because I actually have a mic that uses the connector and i figured that if someone buys it, they might as well be able to use it.

After recapping, replacing the power cord and checking the voltages, I inserted the tubes and tried it- I should have used different speakers because with the Jensen C12R pair, it was only OK but the day I checked it out to sell it, I went through a 12" Eminence and HOLY CRAP! I hit one chord and the first thing I though of to lay was Rumble, by Link Wray. That was a killer amp and if I find another one, I'm going to buy it.

AU-33, only a few miles from here-

Stromberg Carlson AU 33 | Reverb

Recently re capped, tubes tested and a modern speaker output was added.These make killer guitar amps but I tried a bass through it into an old Altec PA speaker and was floored how rich and meaty the tone was!

reverb.com