help valuing parts from 1971 Fender Twin Reverb.

[mikepukmel]

Trying to determine what value in North America for full set of transformers, PT, OT, Choke, Reverb. from a 1971 Fender Twin Reverb chassis.

Currently, works (haven't heard it yet), but many aftermarket parts (resistors, caps), so its not a museum piece.

[The Dude]

Lots of options there, from expensive Mercury to cheap eBay. It's kind of a loaded question. I just have to ask, though. Why do you want to replace all of the iron?

[Justin Thomas]

If you'd said "pricing" parts, I'd guess you want to buy them... are you trying to part the amp out, so want know the values of the parts to sell? Well, I got both the PT & OT to a Twin Reverb for the price of "take all of it, it's free, but only if you take all of it!"

I'm with The Dude here... why worry about the iron? I'd expect lots of parts in an amp of that age to be replaced, especially one that spent a lot of time ON and MAKING MUSIC of the LOUD CRUNCHY kind. Get it sounding great and ENJOY it. Screw what the "collectors" think!

Justin

[Leo_Gnardo]

Depends on who's buying, who's selling, and why.

Twins are a hard sell in my neighborhood. One store owner said "can't even give 'em away." Everybody wants smaller more portable amps these days. Although I have a lot of respect for Twins, it usually takes years to find a buyer when I've fixed up a beater for sale. If you happen to have a Twin owner with an amp that needs those parts I'd say about $120 to $150 for the lot is fair. If you think you can get more, go for it, ka-ching!

[g1]

I think Mike is thinking of buying for the iron, not selling. He mentioned not having heard it yet.

[mikepukmel]

Thanks everyone. OK, it's blasphemy, but planning my next "build", I can get an OK shape Twin Reverb, late 60's, early 70's for roughly 1/3rd the price of building one from scratch, with all new parts. I priced new iron, something like 300.00 (mid range stuff, not junk, not the cadillac's). As Leo wrote above, twin's are a hard sell these days. Very heavy, way too loud, big. Tonally, not very flexible. Musician friends won't even consider one, they want like a little tiny 1 x 10 Mesa combo, with loads of different sonic options, small and light that they can mic and pipe through a PA if they need more coverage. (and they can pop it and the Strat into the back seat of the Mini and heat home after the gig).

Anyway, priced new iron, but wondering what the street value of a full set of used iron would be.

I'm going to pick up a couple of these beaters. Both "play" but rough shape (missing tubes etc).

The idea is to mix two beaters, futz with the circuit to get like a 35 watt somethingoranother out of it, and sell the excess. I have a couple in mind, both in the 600.00 range, both have complete sets of transformers. The transformer set from the second unit would offset the total cost, which is the plan. One of them has a good working circuit board, with new caps/resistors where needed, so Id only have to make small mods to build a lower powered unit.

In not too beautiful shape (end bells a little rusty) but good working condition, 150.00 or 200.00 too high (too low) for 70's transformer set?

(I can't wait to get to work on the FrankenVerb II)

[mikepukmel]

As an aside, Ive been studying period fender amp schematics and was very surprised how similar the whole preamp + reverb + vibrato + phase inverter portion of these amps are. A few components.

[mikepukmel]

Depends on who's buying, who's selling, and why.

Twins are a hard sell in my neighborhood. One store owner said "can't even give 'em away." Everybody wants smaller more portable amps these days. Although I have a lot of respect for Twins, it usually takes years to find a buyer when I've fixed up a beater for sale. If you happen to have a Twin owner with an amp that needs those parts I'd say about $120 to $150 for the lot is fair. If you think you can get more, go for it, ka-ching!

Thanks Leo. I was hoping a little more, but, not very popular amps, and not much else someone can do with those transformers, I guess.

[Leo_Gnardo]

You're getting the whole amp, or just a chassis, or just the transformers for $150-200? I s'pose for a project amp it's an acceptable price range. One thing you could do is run output tubes in triode mode for a mellower tone & lower power. And if you do that you can run smaller, lighter speakers. If you don't mind spending $$$ on neodymium magnet speakers you can save considerable weight there, too.

[mikepukmel]

You're getting the whole amp, or just a chassis, or just the transformers for $150-200? I s'pose for a project amp it's an acceptable price range. One thing you could do is run output tubes in triode mode for a mellower tone & lower power. And if you do that you can run smaller, lighter speakers. If you don't mind spending $$$ on neodymium magnet speakers you can save considerable weight there, too.

Thanks Leo. The whole amp, for 600 range. Will have excess parts I won't use. I don't care about size and weight since once built it will sit next to the window in my basement until Im planted 6 feet under. I may move it to the left a bit to vacuum underneath .

Thanks for the tip on running in triode mode! I'll google around for wiring changes. That would change the output impedance of the tube set, right? I never quite understood what effect changing the output impedance of a set of tubes if the same output transformer is used.

[mikepukmel]

You're getting the whole amp, or just a chassis, or just the transformers for $150-200? I s'pose for a project amp it's an acceptable price range. One thing you could do is run output tubes in triode mode for a mellower tone & lower power. And if you do that you can run smaller, lighter speakers. If you don't mind spending $$$ on neodymium magnet speakers you can save considerable weight there, too.

For half power mode, the screen grid, pin4, is connected through a resistor to the plate? The PLATE?

We'll need a custom circuit that will have a little hammer on a robotic arm. If the user attempts to flip this switch while the amp is not in standby, the robotic arm will hit the users finger with the hammer.

[Enzo]

Yes, connecting the screen of a pentode to the plate makes it a triode.

[mikepukmel]

Yes, connecting the screen of a pentode to the plate makes it a triode.

Thanks Enzo. So I guess this isn't the mod where you have 6 wires sticking out of the back of the amp, and a yellow stickie that says "Twist the greens and blues together for full power, twist the greens and the oranges together for half power".

[Leo_Gnardo]

Thanks Enzo. So I guess this isn't the mod where you have 6 wires sticking out of the back of the amp, and a yellow stickie that says "Twist the greens and blues together for full power, twist the greens and the oranges together for half power".

With the full B+ on those wires that would be definitely the wrong way to go about it. I use a DPDT toggle, and steal the hole where the "ground" switch is to mount it.

[J M Fahey]

Well, yes, exactly that.
Only you drill a hole in the back panel and add a switch to do the wire swapping thingie.

Leave the dangling wires, 2 prong mains plug, death cap and original swelling caps to those who want to "keep collector value" .... whatever that means