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New SET amps

LPD

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I picked up this pair of mono block SET tube amps. Each amp uses a 6X5 rectifier, 6SL7 input and 45 output. Just got them back from the tech for bench testing and will try them tonight. I can share the circuit if anyone is interested.


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Those look nice! The floating heater winding for the 6X5 will help to prevent the H-K shorts common to this tube type (and the 6X4). Those old Akai power transformers are really versatile! Do you know who made the OPTs?

Jack
Good question. I have no idea but can attach a photo of the opt underside and see if it provides any details
 
Look like Alan Eaton, making the transformers Orion and Tamura. I think I have the same amps.

EDIT: And he usually provides 'gently used' 45s with the amps. If they haven't been replaced the amp will sound much better with upgraded output tubes.
 
Mine may be early versions of Alan Eaton amplifiers. They use Hammond chassis, Hammond filament transformers, and maybe Tamura opt. More will be revealed. Mine are very similiar to this Alan Eaton amp on eBay using same capacitors and build layout :)
 

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Are yours mirror image like the amplifiers above?
I have never seen an Alan Eaton built like that.

Mine are not but some of his old ones were mirrored. Looks like he's removed the image I'm thinking about from his site.

This design, with the "vintage military surplus hum rheostat" in the back, 100% Alan Eaton.

EDIT: I guess the pic posted above is from Ebay, but still, thats my guess. :)
 
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Mine are not but some of his old ones were mirrored. Looks like he's removed the image I'm thinking about from his site.

This design, with the "vintage military surplus hum rheostat" in the back, 100% Alan Eaton.

EDIT: I guess the pic posted above is from Ebay, but still, thats

Edit** Spoke with Alan these are his amps and indeed are Alan Eaton SET amps and early mirrored builds. 6AX5 rectifier indeed. Mystery solved.
 
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Mine may be early versions of Alan Eaton amplifiers. They use Hammond chassis, Hammond filament transformers, and maybe Tamura opt. More will be revealed. Mine are very similiar to this Alan Eaton amp on eBay using same capacitors and build layout :)
I have some Tamura output Tx from a Sony TC-500. Did not manage to get the power Tx. Need to do a low budget 45 SET build.
 
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I’m wondering if I would squeeze a little extra power using a 6AX5 rectifier in lieu of the 6X5?

Edit** Spoke with Alan these are his amps and indeed are Alan Eaton SET amps and early mirrored builds. 6AX5 rectifier indeed. Mystery solved.

I was about to ask where you got your schematics, I didn't think that was supposed to be a 6X5 in there.

And I found pics of his older, mirrored monoblocks. I believe he started with mirrored boxes and transformers on the top (your set), then went to mirrored with a transformer inside the case (these pics), then non-mirrored which is what I have. Looks like he's recently re-done his website and scrubbed old product images and data.

As I said I have a set of his 45 monoblocks (selling them soon) and a set of his 300B monoblocks (selling soon for scrap unfortunately). I like his amps but they're a little noisy for my taste. Its a function of the price point and parts used I believe. Nice intro to 45s though.

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I was about to ask where you got your schematics, I didn't think that was supposed to be a 6X5 in there.

And I found pics of his older, mirrored monoblocks. I believe he started with mirrored boxes and transformers on the top (your set), then went to mirrored with a transformer inside the case (these pics), then non-mirrored which is what I have. Looks like he's recently re-done his website and scrubbed old product images and data.

As I said I have a set of his 45 monoblocks (selling them soon) and a set of his 300B monoblocks (selling soon for scrap unfortunately). I like his amps but they're a little noisy for my taste. Its a function of the price point and parts used I believe. Nice intro to 45s though.

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For what I paid for mine it’s a very nice introduction as I am a fraction into the cost of what he sells them for retail. I’m going to find a pair of 6AX5 rectifiers and see how they sound.
 
I have some Tamura output Tx from a Sony TC-500.
I worked with those decks back in the day, but never paid much attention to the OPTs. Do they actually say Tamura on them? I've always wondered who made the OPTs for the old Akai M6, M7, M8. That's what I'm using in my SEP amps. I don't know Alan Eaton, but considering he's using the Akai power transformers, I'll bet he's also familiar with the output iron.

Jack
 
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I worked with those decks back in the day, but never paid much attention to the OPTs. Do they actually say Tamura on them? I've always wondered who made the OPTs for the old Akai M6, M7, M8. That's what I'm using in my SEP amps. I don't now Alan Eaton, but considering he's using the Akai power transformers, I'll bet he's also familiar with the output iron.

Jack
Jack, everything I have seen on this and other forums claim those to be Tamura. Only EIA numbers I see 1-427-041-05. Has the 600 ohm winding and 8ohm. I haven't put much research on the codes. Hey, I just realized they came from @tubeactive.
 
Please tell me that should be a 6SN7 rather than a 6SL7. ;-) Otherwise there would be an insane amount of gain, plus the resistor values would be way off. With a 6SN7 it's basically a JELabs 300B amp with a 45. And there's no need to bypass the input stage cathode. Even with a 6SN7 that's still excessive gain.
 
The typical Alan Eaton build is NOS 6AX5, used 6SN7 and 45 tubes, Tamura output transformer, Orion power transformer.

Not sure where the schematics above came from, I've never seen any posted before. I suspect the 'tech' mentioned drew them up and either mistyped or guessed about tubes?
 
Please tell me that should be a 6SN7 rather than a 6SL7. ;-) Otherwise there would be an insane amount of gain, plus the resistor values would be way off. With a 6SN7 it's basically a JELabs 300B amp with a 45. And there's no need to bypass the input stage cathode. Even with a 6SN7 that's still excessive gain.
It’s a 6SN7 :)
 
The typical Alan Eaton build is NOS 6AX5, used 6SN7 and 45 tubes, Tamura output transformer, Orion power transformer.

Not sure where the schematics above came from, I've never seen any posted before. I suspect the 'tech' mentioned drew them up and either mistyped or guessed about tubes?
It was a guess and having done some research and discovering the amps were indeed Alan Easton’s I have 5692 input drivers and ordered a pair of 6AX5 rectifiers :)
 
I was about to ask where you got your schematics, I didn't think that was supposed to be a 6X5 in there.

And I found pics of his older, mirrored monoblocks. I believe he started with mirrored boxes and transformers on the top (your set), then went to mirrored with a transformer inside the case (these pics), then non-mirrored which is what I have. Looks like he's recently re-done his website and scrubbed old product images and data.

As I said I have a set of his 45 monoblocks (selling them soon) and a set of his 300B monoblocks (selling soon for scrap unfortunately). I like his amps but they're a little noisy for my taste. Its a function of the price point and parts used I believe. Nice intro to 45s though.
What happened to the 300B's?
 
 
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