vintage fender transformers info?

[johnny blackwater]

I recently scored several crates full of old fender and marshall transformers from a family run music store that went out of business, the majority of the fender transformers are pre-1968 (cloth wire). I am considering building some reproductions of some vintage amps I can`t afford to buy. My friend told me that with the original transformers, I could probably scrounge up enough NOS resistors, capacitors and other parts to get a 95% accurate reproduction (sound-wise) of some Fender black-face amps. I have a complete set of transformers for a `67 Deluxe Reverb, `63 twin reverb, 2 Princetons, and a `57 Tweed Deluxe,amoung others. My friend says that the transformers are a very large part of the sound of a vintage amp, any opinions? Can I test the power and output transformers on the bench without a load? should I use a variac set at 10% of wall voltage (110V)? Thanks!

 

[greco]

Re: vintage fender transformers info?

I recently scored several crates full of old fender and marshall transformers from a family run music store that went out of business, the majority of the fender transformers are pre-1968 (cloth wire). I am considering building some reproductions of some vintage amps I can`t afford to buy. My friend told me that with the original transformers, I could probably scrounge up enough NOS resistors, capacitors and other parts to get a 95% accurate reproduction (sound-wise) of some Fender black-face amps. I have a complete set of transformers for a `67 Deluxe Reverb, `63 twin reverb, 2 Princetons, and a `57 Tweed Deluxe,amoung others. My friend says that the transformers are a very large part of the sound of a vintage amp, any opinions? Can I test the power and output transformers on the bench without a load? should I use a variac set at 10% of wall voltage (110V)? Thanks!

You lucky dog, you !!

I'm just getting into building an amp, so this interests me.

I will give my opinion(s) just to see what others say about them. Please wait for the others (ArtieToo, Scott_F and many others that I can't think of quickly) to comment.
I don't trust my knowledge here.


Quote "I could probably scrounge up enough NOS resistors, capacitors"
These parts can be found, but the old carbon comp resistors will tend to drift in their resistance values and might not have good tolerances. Old caps might not be the best idea as they can leak. Some folks claim that the secret to the "mojo" of old amps is to use old components (including wire) but many will dispute this especially given the costs associated with buying NOS stock. I saw 2 NOS filter caps for sale recently for $125.00 US. for the pair.


Quote "My friend says that the transformers are a very large part of the sound of a vintage amp, any opinions? Can I test the power and output transformers on the bench without a load? should I use a variac set at 10% of wall voltage"
I think that your friend might be right about the transformers. I think that you will need some type of load on the transformers for testing to prevent them from being damaged. I'm not sure that you really need to use a Variac
at low voltages, especially as you want to know the actual measure of the output voltages.

Do you know of any site that lists the transformers (i.e., models /codes ...or what ever the correct terminology for their identifiers is) used in old (60' and 70's) Fender amps? I can't seem to find a source.

I'm going to be watching this thread with interest.

Again, nice score !!

Dave

 

[Fresh_Start]

Re: vintage fender transformers info?

Johnny - that iron is an important part of the vintage sound IMHO. Dave's right about NOS caps and resistors though (also my opinion, and others will disagree). Also, there may be modern layouts for the vintage circuits that produce less noise. Check out the Library at Hoffman Amps, for example. Actually, you might want to post over there about testing your trannies.

I think you can test power transformers OK, but need to know that the voltage will read high without the proper load. Don't know about testing an output transformer.

I would ask you whether or not the Princeton transformers are for a Blackface Princeton Reverb... but dare not! Christian would hunt me down

Dave - the Ampwares Fender Field Guide has the vintage schematics, and they usually list transformer part numbers. Same for Schematic Heaven.

Chip

 

[Scott_F]

Re: vintage fender transformers info?

Well, those trannies are potentially valuable. I'd hate to see you fry one or two not knowing what you are doing. But, hey. they belong to you now.

Maybe build a cheap Weber kit before you use those trannies.

 

[WhoFan]

Re: vintage fender transformers info?

ya i bet there is lots of people out there that would pay for old trannies... if they work 100% of course.. be careful not to damage them

 

[More-Gear-Than-Skill]

Re: vintage fender transformers info?

Consider checking what they're worth as is. Building up an amp around the iron is perhaps like building a Ferrari because you have an original engine?

I agree that the iron is key to the mojo, but it goes along with all the other bits. Maybe you could get vintage amps with the iron blown/replaced, real cheap and put those trannies where they belong?

A restored 100% original correct amp, will ultimately be worth more than a built up-around-iron one.

Build a weber from current iron, and find a dear old blackface that's crying for a proper transformer....then rock

 

[johnny blackwater]

Re: vintage fender transformers info?

I think I will put the older transformers up for now, I checked some prices on vintage Fender amps, and with a blackface Vibroverb selling for over $5,000.00 I can imagine what an original transformer will be worth.
I have repaired lots of amps, but have never built one from scratch. I`m thinking about starting with an 18 watt Marshall project, I have an interesting piece of audio equipment to start with, It`s a 1960 4-track Fidelipac tape player/P.A. Check out the size of the cassette!! can you imagine carrying around a box of these in your car? The owner of the store said that it didn`t sell, and he got stuck with it when the format was discontinued. I have removed the tape player internals, and have been playing guitar through the mic input, it sounds pretty good but it could use a tone control, the high end is rolled off substantially. It came equipped with two 12ax7`s , two EL84`s , all Telefunken`s, and an RCA 5y3GT rectifier tube. seems like a good start, I also got an early Ampeg Gemini 12 combo, a 1965 Gibson GA-75 Recording amp, a `72 Ampeg V2 head, and a 1956 Les Paul Junior amp In the deal, all in various states of disrepair. maybe after I fix these I will be ready to build a Vibroverb or a Twin.

 

[ES350]

Re: vintage fender transformers info?

Ummm, the question is: why are they in a crate in the back of an old music store ? That's typically where dead ones are buried...

As far as blue Mallorys, Astrons, and all the rest of the stuff you would need to make a vintage clone, they are getting scarce and pretty expensive, and a lot of it almost certainly out of spec. Add in chassis, pine cabs, vintage speakers, build and troubleshooting time, and you might as well just go buy the real thing.

 

[greco]

Re: vintage fender transformers info?

, I also got an early Ampeg Gemini 12 combo, a 1965 Gibson GA-75 Recording amp, a `72 Ampeg V2 head, and a 1956 Les Paul Junior amp In the deal, all in various states of disrepair.

You must be kidding!:yell:

PLEASE....Any chance of some pics of these old amps:fingersx: ? Thanks.

Lots of enthusiasts of old amps in the forum.

Many interesting comments/approaches in the thread so far. Are you a bit confused as to what to do?

Dave

 

[WhoFan]

Re: vintage fender transformers info?

I think I will put the older transformers up for now, I checked some prices on vintage Fender amps, and with a blackface Vibroverb selling for over $5,000.00 I can imagine what an original transformer will be worth.
I have repaired lots of amps, but have never built one from scratch. I`m thinking about starting with an 18 watt Marshall project, I have an interesting piece of audio equipment to start with, It`s a 1960 4-track Fidelipac tape player/P.A. Check out the size of the cassette!! can you imagine carrying around a box of these in your car? The owner of the store said that it didn`t sell, and he got stuck with it when the format was discontinued. I have removed the tape player internals, and have been playing guitar through the mic input, it sounds pretty good but it could use a tone control, the high end is rolled off substantially. It came equipped with two 12ax7`s , two EL84`s , all Telefunken`s, and an RCA 5y3GT rectifier tube. seems like a good start, I also got an early Ampeg Gemini 12 combo, a 1965 Gibson GA-75 Recording amp, a `72 Ampeg V2 head, and a 1956 Les Paul Junior amp In the deal, all in various states of disrepair. maybe after I fix these I will be ready to build a Vibroverb or a Twin.

nice variac in the first photo

 

[Rich_S]

Re: vintage fender transformers info?

That tape player is COOL, and yes, it's begging to be turned into a 18 Watter. The Lite II variant will work with the tubes you have now - that 5Y3 is close enough to the Marshall's EZ81 that it's not worth changing to the smaller socket.