6AK6 push-pull output transformers

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tube geek
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Joined: Sat May 29, 2010 2:11 am

6AK6 push-pull output transformers

Post by tube geek »

I'm working on a 6AK6 push-pull project, and I am looking for suggestions on output transformers. I believe s2 used a Mercury, and I have found no info on the Dynotweed OT. I am also seeing 5k to 20k being used. What have you had luck with? :?:
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Phil_S
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Re: 6AK6 push-pull output transformers

Post by Phil_S »

Duncan's TDSL says that Zout=10K.
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FYL
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Re: 6AK6 push-pull output transformers

Post by FYL »

The 6AK6 is a 7-pin version of the 6G6. Same operating points etc.
mcrracer
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Re: 6AK6 push-pull output transformers

Post by mcrracer »

MPS has a 22.5k / 4,8 and 16 ohm
and Weber has a 20k , 10k / 4 or 8 ohms
both priced right.
BT123
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Re: 6AK6 push-pull output transformers

Post by BT123 »

Hello,

1st post. I have an S2 Micro amp w/6ak. I don't think the transformer is a Mercury. I can open it up and take a few gutshots if you want.
tube geek
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6AK6 push pull output transformers

Post by tube geek »

Thank you BT125,
A couple shots of the transformers would be nice. If you could make note of the transformer numbers that would be way cool, and much appreciated.
BT123
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Re: 6AK6 push-pull output transformers

Post by BT123 »

Will do - although it might be a day or two before I have the time. I have two of them - 1 is the M1 blackface style with the 2 X 6AK6 tubes, and the other is the M3 Wreck style with 2 X EL91.

From the outside they appear to be the same transformer set.
Chappy
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Re: 6AK6 push-pull output transformers

Post by Chappy »

BT123

I am also considering building a PP with 6AK6 and another with EL91's. How do your S2 amps sound?
Chappy
Cliff Schecht
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Re: 6AK6 push-pull output transformers

Post by Cliff Schecht »

I prefer the 10kCT for 6AK6's, 20k is a bit high and sounds weaker IMO. You can always play around with impedance mismatching on the secondary side to see how different primary impedances sound.
Cliff Schecht - Circuit P.I.
BT123
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Joined: Sun Dec 28, 2008 9:35 pm

Re: 6AK6 push-pull output transformers

Post by BT123 »

Okay here are some shots. Sorry for the poor picture quality. I couldn't see any #'s on the transformers, so hopefully someone here will recognize what they are.

[img:1024:768]http://i195.photobucket.com/albums/z235 ... p005-1.jpg[/img]

[img:1024:768]http://i195.photobucket.com/albums/z235 ... Amp004.jpg[/img]

[img:1024:768]http://i195.photobucket.com/albums/z235 ... Amp003.jpg[/img]

[img:1024:768]http://i195.photobucket.com/albums/z235 ... Amp002.jpg[/img]

[img:1024:768]http://i195.photobucket.com/albums/z235 ... Amp006.jpg[/img]
BT123
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Re: 6AK6 push-pull output transformers

Post by BT123 »

I really really like these amps. The M1 is a blackface style amp that is a great pedal platform. I've heard the 6AK6 described as sounding like a small 6L6 and I think that is spot on. While it doesn't have the girth of a 6L6 for clean tones, it does sound surprisingly big and full. Blasting it with a Menatone Kar Krash or a Lovepedal Eternity at bedroom volume sounds crazy good.

The M3 is the Wreck copy. The EL91s sound like smaller EL34s. Really the same comparison as above. Fantastic saturated tone.

I really like going back and forth between the M3 cranked and the M1 with a Kar Krash pedal. They are not the same, but both crazy good and you can tell the sound is somewhat related.

It does look like both transformer sets are the same and you can see in the M1 photos that it looks like you can interchange 6AK6 and EL91 by flipping a switch.
Chappy
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Re: 6AK6 push-pull output transformers

Post by Chappy »

BT123

Thanks for the pics and the description of the amps. I can`t wait to get started on my builds. They sound like the perfect amps for me for home use only.

Cheers
Steve
tube geek
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Re: 6AK6 push-pull output transformers

Post by tube geek »

BT123,
Thanks for the photos, even though there are no numbers on the trannys the shots were cool to look at.
Thanks for the effort,
Tube Geek
Cliff Schecht
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Re: 6AK6 push-pull output transformers

Post by Cliff Schecht »

The first thing that comes to mind when looking at those trannies is Hammond. At least for the bigger one, it looks like a 272 series.
Cliff Schecht - Circuit P.I.
Chappy
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Re: 6AK6 push-pull output transformers

Post by Chappy »

Before S2 shut down his website I took some notes to help me with my builds. All three of his small amps used Mercury Magnetics transformers. Images I have of the "Wrecktified" and the "Blackface" show black transformers without any labelling. His "Van Plexi" also used MM trannys but these were not painted black. Unfortunately I cannot make out the labels on the low quality image that I have of the Van Plexi amp.

Steve
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