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Allen Organ 6L6 amp

dnewma04 said:
I had Allen 20s with the same output transformers and also have had a couple of pairs of TO-300s. If there is a difference, I wasn't able to identify it. A lot of research seemed to point me to a point where Allen stopped mfg their own transformers and started sourcing OEM units from Acro. In fact, my Allen 90s clearly say mfg by acro transformer company and have the exact same specifications as the TO-330.

The 40 did share signal schematics with the 20s. The Allen 75 was a SS rectified push pull 6550 amp with TO-330 outputs and the Allen 90 a push pull 6550 amp w/ dual 5R4 rectification which used various output transformers including some websters on early models and the Acro's like mine.

There is some talk on the net about a Saratoga transformer company getting into the mix at some point but I can't recall the evolution.
Click to expand...

Thanks for the info!

The OT on the 75s has Acrosound printed on them as well. The ones on the Type 40 are a spitting image of the TO-300 and it would make sense that when they were sourcing their OTs from Acrosound for the 75s and 90s that sourcing them for the Model 40s as well would be most economical.

Now I'm getting excited about this amp!!!!

Should have a sound that is equal to many other 6L6 amps that cost a lot more. Surprising that they aren't more popular. Guess it's the industrial look to them. Personally I like that though, just like the early Mac theatre amps!

Cheers

Lar
 
diamondsouled said:
Wow! Nuff iron there to start a foundry lol.

The bigger gold ones are Model 90s correct?

Must have come with some Tung Sol 6550s I imagine. Wish I could score a quad of the black plated ones. :tears:

Lar
Click to expand...

Yes, the big ones are the 90's. Above that, you can see a pair of 20's just to the left of the Conn 6L6 monos and then, another 90. On the rack on the right, my last remaining pair of Model 75's.

I have never heard a 40, but well worth a recap and restore I would bet. I sure love my Model 75's :thmbsp:

Most everything (75's and 90's ) had Tung Sol 6550's. A few were missing but some were just pulled for testing.

RC
 
Allen amps

Hello!

I have a pair of Allen type 20s that have been sitting on a back shelf. Many moons ago I read something that they weren't considered "hi fi" material, perhaps I was mislead?
The output trannys look plenty large for 20 watts!

I did find a copy of the diagram on line way way back, but now I'm unable to locate it. Anyone know where I might have found it?
 
m12ax7 said:
Hello!

I have a pair of Allen type 20s that have been sitting on a back shelf. Many moons ago I read something that they weren't considered "hi fi" material, perhaps I was mislead?
Click to expand...


Boy I hope so! I'm really looking forward to getting mine done some someday.




jaymanaa said:
Those Conns look vaguely familiar.:D
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Sans chrome and pretty much everything else :D

RC
 
Here's that post from May 30 2000 from rec.audio.tubes:

Allen Organ evolved in their amplifier production from contracting the
manufacture of amps with Webster Electric to producing their own. There were several models considered to be "extended range". Two of those are KT88/6550 based, but one is 6L6 based. It is known as a "Type 40". A photo can be found at the following site:
http://www.digitalvideo.com/hifi/images/type40.jpg
It is a two channel amp that may use Acrosound TO-300 as output
transformers. I am not at all sure of this, but there was history of Allen Organ using Acrosound TO-330 output transformers in their early (6550) Type 75's.
Both of the larger extended range monoblocks, type 75 and 90, can be
"very" good as audiophile amps. Build quality and stability are excellent. The
sound produced is as good as I have ever heard. I have never heard a Type 40 though.
There were other, non type 40, Allen 6L6 amps made, so be careful. I would risk the purchase for the chance to experiment with a type 40, but not other amps.
By the way, if you hear about a source for a single Allen type 90, "please
let me know". I've been looking for a second one for quite a while now. The
output transformer need not be good. I have a replacement.
Hope this helps.

---------

:D

Lar
 
I have posted Allen 20 schematics here in the past. Not sure if I still have them handy. My 20 now resides on that second shelf. :)

I think i recognize some sort of hammond PPP 6V6 amps on the bottom shelf. These are also supposed to produce some top notch audio.
 
dnewma04 said:
I have posted Allen 20 schematics here in the past. Not sure if I still have them handy. My 20 now resides on that second shelf. :)

I think i recognize some sort of hammond PPP 6V6 amps on the bottom shelf. These are also supposed to produce some top notch audio.
Click to expand...


Jef at Abraxas Audio has done up some nice amps with them (Webster/Hammonds). I spoke with him some time ago about doing a pair for me, but he was so backlogged with work at the time he couldn't take them on. He wires them for switchable SE/PP and said that he actually preferred PP in that amp. Claimed that he was surprised at how little regard people had for the 6V6 as compared to other output tubes. He said that they made for a very nice audio amp.

RC
 
While the Acrosound transformers had the name, it was my understanding that virtually all the Allen tube amps had pretty much the same transformer specs in terms of frequency response.

I have a pair of 20s from 1961-62, and a pair of 90s from 1958. The transformers on the 90s have no identification, but the units match in virtually every way.

The chassis and tube sets on the 20's match, but one of transformers is different (although all are OEM). One is a Stancor, while the other has the same Allen Organ parts code (85-0) but no branding. It is the same size as the Stancor, a different mounting mounting configuration, and an EIA code of 174, which I can't track. In fact, the chassis of the 20 was designed for this unknown, as the Stancor doesn't make use of the mounting holes. I haven't refurbed the 20's so its hard to say whether there is any sonic difference.
 
dnewma04 said:
There is some talk on the net about a Saratoga transformer company getting into the mix at some point but I can't recall the evolution.
Click to expand...
The 75s I own have Saratoga labeled transformers, and between the two there are different designators. I don't have them in front of me right now but I recall the numbers being the same, but one is "-B" version (ie. ### and ###-B). I'll have to check later. The transformers appear to be identical but I can't see through the potting... :rolleyes:
 
Help? Maybe not. It does legitimize the confusion, though. Not sure if thats a good thing or not... Thanks. :)
 
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Well, here's the last one.
 

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