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Hey amp gurus, maybe you can help me with this head scratcher. Vintage tube combo, 1 mic input, 2 instument inputs, 1 volume control. The amp has 1 12AX7 pre amp tube and 1 7591A power tube. Any info would help, I want to make a head out of it, for at home practice...I don't even know what ohm speaker I should get for a cab. Thanks. Here are some pics.

More pics

I could be wrong, but I think it may be an old BOGEN amp-


Originally Posted by marvarI could be wrong, but I think it may be an old BOGEN amp-

I suppose it could...usually they had their name on them. I'm wondering if it is a montgomery ward or something that was made by one of the big boys as a budget model.

Seems like I've seen some old Altec amps that had that same type front panel

Aren't the Altecs generally more green/teal in appearance?

And all the Altecs I've seen have Altec blazed across the face.

It's a DuKane - the cosmetics are identical to a 2xEL84, 20-watt PA amp I parted out a while back. Kind of like this one.

DuKane made (makes?) audio-visual equipment for schools, civic auditoriums, churches, etc. That amp was most likely a built-in amp for a small compact PA or maybe a filmstrip projector. Show of hands - who remembers filmstrip projectors?

If you want to play it as-is, take a guess at 8 ohms, assuming you know which wires are the output.

If you need to identify the correct speaker wires, you'll need to test the output transformer to figure out its turns ratio. The 7591A wants a load around 3000 ohms, so we could figure out what the speaker impedance should be from there.

With minor tweaking, that amp looks like it could be converted to run a 6L6 in the output stage, sort of a quot;Super Champquot;. It probably puts out close to 10 watts, which is unusually high for single-ended amps. It might also be possible to convert it to a regular Champ, if you make some allowances for speaker impedance. Also, changing to a 3-wire grounded power cord is highly recommended.

Anyway, it's cool amp. It's super-simple design amp; construction make it an ideal educational project. Respond here or PM me if you want help with the next steps.


Originally Posted by Rich_SIt's a DuKane - the cosmetics are identical to a 2xEL84, 20-watt PA amp I parted out a while back. Kind of like this one.

DuKane made (makes?) audio-visual equipment for schools, civic auditoriums, churches, etc. That amp was most likely a built-in amp for a small compact PA or maybe a filmstrip projector. Show of hands - who remembers filmstrip projectors?

If you want to play it as-is, take a guess at 8 ohms, assuming you know which wires are the output.

If you need to identify the correct speaker wires, you'll need to test the output transformer to figure out its turns ratio. The 7591A wants a load around 3000 ohms, so we could figure out what the speaker impedance should be from there.

With minor tweaking, that amp looks like it could be converted to run a 6L6 in the output stage, sort of a quot;Super Champquot;. It probably puts out close to 10 watts, which is unusually high for single-ended amps. It might also be possible to convert it to a regular Champ, if you make some allowances for speaker impedance. Also, changing to a 3-wire grounded power cord is highly recommended.

Anyway, it's cool amp. It's super-simple design amp; construction make it an ideal educational project. Respond here or PM me if you want help with the next steps.

Hi Rich amp; Thanks. I will surely shoot a P.M. to ya tonight when I get home....turning it into a champ was what I was hoping I could do. Sounds very cool.....Thanks again......Joe