• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

What vintage gear to source for tubes and transformers?

Sultanen

Member
2016-01-30 7:31 pm
What kind of vintage electronics would you guys look for when sourcing tubes and transformers for a tube-amp build?

From what ive come up with you can find audio tubes in:
  • Organs
  • Radios
  • Tape-players
  • Car stereos
  • Guitar amps and Hifi amps

What have i missed?

(Yea. I know its a shame to destroy old electronics and all that.. I'll try to find gear that is broken in some non electrical way to make it less of a pain :) )
 
What kind of vintage electronics would you guys look for when sourcing tubes and transformers for a tube-amp build?

From what ive come up with you can find audio tubes in:
  • Organs
  • Radios
  • Tape-players
  • Car stereos
  • Guitar amps and Hifi amps

What have i missed?

(Yea. I know its a shame to destroy old electronics and all that.. I'll try to find gear that is broken in some non electrical way to make it less of a pain :) )
All of the above is rare today.
Buy what you need (instead of build what you get), sources are like tubetown de etc . Also ( you did not state your location ) radiomuseet göteborg sells a lot of what you might need, local ham groups if you can find might also be of help.
 

Welcome

Member
2013-03-11 10:52 am
Indeed, anything you will find in the things you listed won't be suitable for hi-fi. You may be able to get sound out of it, but it won't be pleasant. Old used worn out tubes mostly aren't worth your trouble either, certainly not power tubes, better to get brand new stuff.
 

Sultanen

Member
2016-01-30 7:31 pm
Thanks alot for the input guys!
Oscilloscopes that are tube based generally have power transformers with a TON of secondaries.

Hi,

Juke boxes, cinema amplifiers and PA amplifiers. Though
the latter are unlikely to have suitable output transformers.

rgds, sreten.
Thanks for the sources! Now i have more options to search for :)
If you find an OPT in a hi-fi amp then best to simply rebuild the amp i.e. repair it. Any other OPT is unlikely to be suitable for hi-fi, although you could use it in a guitar amp or a wireless set.
Yea, i don't think that i would rip apart an old Hifi amp, maby rebuilding a guitar amp to adopt it to hifi. Im not after reparing but rather scratch build for the pure sake of the learning experience that will end up in an awesome looking great sounding amp to drive my front speakers in my livingroom :)

Indeed, anything you will find in the things you listed won't be suitable for hi-fi. You may be able to get sound out of it, but it won't be pleasant. Old used worn out tubes mostly aren't worth your trouble either, certainly not power tubes, better to get brand new stuff.
Okey, so you only recommend buying new tubes? I love repurposing old stuff so buying new would feel like a shame or last resort if its really not an option using old tubes.

All of the above is rare today.
Buy what you need (instead of build what you get), sources are like tubetown de etc . Also ( you did not state your location ) radiomuseet göteborg sells a lot of what you might need, local ham groups if you can find might also be of help.
Yea, they are quite rare ive noticed. Even if they are quite cheap they are hard to find. In Sweden, where is the best place to find this kind of stuff apart from Blocket?

I kinda like your idea of buying used tubes, i have never been to Radiomuseet in Gothenburg but i will try to pay them a visit asap :) I live in Borås so its close! I guess that they would probably have most that i need like tubes(saw the huge list on the web), sockets and OPT?

Whats "local ham groups" btw?
 

anatech

Administrator
Paid Member
2004-06-06 8:31 pm
Georgetown, On
Hi Sultanen,
A HAM is an amateur radio operator. They typically are experts in their knowledge of electronics and how it applies to their hobby. Most will assist younger folks in learning more. They may have transformers on hand as they tend to be pack rats - just like other electronics hobbyists.

Power tubes are normally worn by the time you find them in discarded equipment. Once you have something built, use new tubes to run it. Experiment with the old ones. Tubes that test bad - pitch them, or make ornaments out of them. A bad tube that can possibly be mistaken for a used good one will provide you with hours of troubleshooting experience.

-Chris
 
Sorry but I think that will not help much:
a) there is not much left, if any, most everything is in a landfill by now.
b) recycling old parts (resistors/capacitors/sockets/etc) means old humid rusty bulky noisy leaky parts with way too short leads: unusable.
Believe me, I've been there, filled a room with crap out of which I could only pull a few polyester caps, not worth it.
Forget oil filled caps and even more electrolytics.
And parts will never match what you need.
Mind yo, I once bought 800 noval sockets and some 200 octals at an auction , that was worth it (I make guitar amps) , in another I bought 1000 Russian ECC189 & PCC189 for U$250 (25 cents each) , measured then (drew my own datasheet curves) and built Guitar Distortion pedals and preamps with them.

In both cases I had "a lot of the same" so it paid to specially design something and producing it , but what will you do if you buy an organ and find 44 12AU7 inside ?
Or a TV set with 17 *different* tubes?
15 of them unusable "TV tubes" plus a 5U4 and a 6AQ5?
And a tiny cheesy 2W output transformer and a *huge* power transformer meant to power those 17 tubes?

So it's best to just choose a project you like, get parts from a regular supplier and enjoy :)

Leave "building something with *anything* they can get" to desperate POWs in a prison camp trying to know how's War going on:
P8130404.jpg
 

ericj

Member
2008-12-08 10:24 pm
I've got a dozen 6cb6 in a bag here, was in a box of misc. electronics from an estate sale. All branded tektronix, probably from an old scope. but are any of them good?

There was a time for scavenging junk piles for tubes and it was called the 1970's.
 

Sultanen

Member
2016-01-30 7:31 pm
Okey guys! You have convinced me and i have to admit it feels rather good! :) I will go to this radio museum during the weekend to see what i can find there.
It may be outside the scope of this thread but i've been looking at Tubelab's SSE as a posible circuit to build. Is it good and what options do i have for other simple stereo hifi tube amps?
I will probably use it to drive the front speakers of my surround system(used both for movies and music). The speakers and crossover design:
http://www.diyaudio.com/forums/multi-way/286128-2-way-speakers-suggestions-improvements.html
 
Last edited:
Scrounging old TV and Radio stuff usually just ends up with a bunch of RF and IF tubes that are pretty much useless anyway.

Take a look at the $1 list:
Summer Dollar Days - Vacuum Tube Sale - $1.00 Vacuum Tubes

Some $1 tubes of interest for audio on the list:
6HZ8, 6LY8, 6CM7, 6JC6, 12HL7, 6AG9, 6JZ8, 6BN11, 6FJ7, (6J10/6T10/6Z10)

Some other very useful tubes on the regular price list: 6CB6A $3, 6EW6 $4, 6JN6/6GE5 $6,

Then over here:
Vacuum Tubes prices. Best prices every day!
Get yourself a half dozen 6HJ5 and/or 21LG6 for $4 each.

You can now build most any audio amp equivalent with that selection. (But don't expect to find these in old audio schematics, you will have to learn how to use them. These are higher performance tubes anyway. 6CB6A and 6JN6 (or 6EW6 and 6HJ5 for a 75 Watt output amplifier) can be used for a popular DCPP amplifier on the forum.)

Now you can concentrate on transformers. Power and Output types.
 
Okey guys! You have convinced me and i have to admit it feels rather good! :) I will go to this radio museum during the weekend to see what i can find there.
It may be outside the scope of this thread but i've been looking at Tubelab's SSE as a posible circuit to build. Is it good and what options do i have for other simple stereo hifi tube amps?
I will probably use it to drive the front speakers of my surround system(used both for movies and music). The speakers and crossover design:
http://www.diyaudio.com/forums/multi-way/286128-2-way-speakers-suggestions-improvements.html
If you can visit radiomuseet during wednesday afternoon you will encounter a
lot of interesting persons. Bring "fikabröd" with you and you will have a nice and informing chat with the inmates!
 
Last edited:
I'm really cheap and look around a lot for creative solutions for transformers.

If you don't mind building ugly a lot of small industrial transformers make good B power transformers, at least the in the US, and are often really cheap. Typically split primary/split secondary to be wired in various ways. 120/120 | 240/240 are useful. Other voltages exist, but it's a limited set. They hum like heck and are un-shielded so you you need to put then in a separate box several feet from the amp (or whatever) and run wires to them. I've build an amp and a couple or radios this way.

A source for dirt-cheap (free if you don't mind dumpster diving) filament transformers are old UPS power supplies. These are usually 12V, lotsa amps, but all the caveats above apply in addition to the cores not being well insulated from the windings (says so right on the transformer) so they need to be insulated from the box you stick them in. Also you need to use 12V filament tubes or 6V ones in series, which doesn't always work out.

For output transformers the only trick I've found is that sometimes poorly rated ones behave OK if you only run them at 1/4 to 1/2 the rated wattage. You also might get lucky with toroid power transformers, but it depends so much on the cores (which isn't something that's usually described) that it's a crapshoot. I found one good one and got excited and bought several more on E-Bay that were all crap for audio. Really there seems to be no way around buying good ones. I have found some really good broadband *input* transformers that were intended for scientific instruments, not amps, but this was just pure luck.
Everything else I buy new.