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Organ - Allen model 20a amp

BmWr75

Top octave? pfffffftttttt
Subscriber
Thanks to a heads-up by @StephenJ, I took a ride to look at an Allen organ yesterday. Ended up bringing it home. Tube compliment is three 6L6GC, one 5U4, one 12AT7 and one 12AU7. The 3rd 6L6GC is in the other unit with all the transformers.

Anyone refurbed one of these for Hi-Fi use?

@jaymanna - you are not losing it, I deleted the thread that got moved to D&S. Sorry for posting the CL link to the other Allen organ in the original thread, I forgot about that rule.

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Do the caps shown in the 4th picture have any chance of still being good?

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There is a bunch of them isn't there? Was more wondering if they are worth salvaging for use in future rebuilds?
 
You will hate yourself later if you do , toss then out or sell them to some one that will restuff them for an old radio or TV that they want to look original .
 
Hiya,

That looks like a tone control type of board .. Hard to imagine that is actually in the main Allen 20 Amp itself .. So unless you are planning to use this as an actual Organ you would not be re-capping that.

Frannie
 
It is trash day tomorrow. One Allen organ has been deconstructed. :D

Amp and speakers salvaged.
 
Circuit shots

Bottom side pictures

All I need now.......is another one. :scratch2:

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And now we have a pair of Model 20as with identical circuits. The cosmetics on the transformer covers are different, but that is all I can see different. Time to start ordering new capacitors.

Thanks @rooferben!!

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Cool biz !!

Ben is a great guy,I've had the pleasure of meeting him.He even delivered a couple of cases of Yuengling to AK Fest 2012 for me.
 
Refurb complete

Finished up the recapping of these two amps today. One of the easiest I've done. Plenty of room to work, not too many caps to replace. Yep, those are honkin' huge 30uF film caps hanging on the output transformer case. No room on the underside for them. Used Russian PIO coupling caps from Jim McShane.

Need to find some nice looking wood blocks to screw to each end and act as feet.

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The cap is between the transformer output and the 8 ohm speaker tap. There was a 30uF 25V nonpolar electrolytic there originally.
 
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Have only heard them on my bench speakers so far, which are very small. They sounded a little bass shy, but it could be the speakers.

Am wondering if that 30uF cap is significantly rolling off the bass on the 8 ohm tap??? I know some speakers, e.g.,, Dynaco A25, use one cap in the crossover to protect the tweeter from low frequencies.

Guess I could try the 16 ohm taps that don't use the cap and see if the bass is better. Need to set the amps up with some full range speakers first.
 
Yep, there is no bass with the 30uF cap in place. This must have been the output that drove the tweeter/midrange in the organ. Will have to remove the 30uF caps tomorrow and try it again.

Tried the 16 ohm taps, but there is no output on them from either amp. :scratch2:
 
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