mystery triad output transformer

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jujudubluz
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mystery triad output transformer

Post by jujudubluz »

hey guys,
a friend just gave me an old hospital p.a / amp... took it because it looked cool with its mxr type knobs and vu meters... anyway, opened it back home and found the thing to be totally handwired, loaded with quality tubes, triad transformers and green molded cde caps...

i googled it and here's the sole info i found about it...

http://www.indianaradios.com/Grason%20S ... lifier.htm

the one i own is the one with the 33' record player in the middle of the page...

do you guys think i should salvage it and just use it for parts or do you believe modding it would be possible ... to which kind of circuit...???

huh and since it runned 4 6v6 tubes in stereo, the amp is loaded with 2 triad "2541" output transformers... does any of you happen to have a data sheet for this output xformer....?

lemme know.

juju :roll:
"less is more" mies van der rohe
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skyboltone
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Re: mystery triad output transformer

Post by skyboltone »

Certainly the power and output transformers could form the basis of just about any 6V6 or EL-84 amp you can think of. You need to determine the turns ratio of the OT, square it, then multply by the chosen speaker ohm value. There are multiple discussions on how to do that here on the board.

My guess is that the transformers are in the neighborhood of 8.5K to 10.5K into 8 ohms.

If you've not got a fair amount of experience with this sort of thing it's time to smarten up on technique and safety for tube amplifier work. My suggestion is to start with the AX84 site for good beginner information.
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jujudubluz
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Re: mystery triad output transformer

Post by jujudubluz »

hey skyboltone,
thanx a lot for the reply... did you noticed your "666" posts ha ha...?
regarding experience, i would say i'm neither a novice nor an experimented builder... the same person who gave me that amp is a local tech i've been knowing for years... and guided me to build a 5E3, mod a bassman and build several stompboxes... i like to work at his place, thus, whenever i have a question, he usually can answer it... but you're right... should be time to do it on my own.... since he will soon retire...

anyway, thanx

juju
"less is more" mies van der rohe
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skyboltone
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Re: mystery triad output transformer

Post by skyboltone »

jujudubluz wrote:hey skyboltone,
thanx a lot for the reply... did you noticed your "666" posts ha ha...?
regarding experience, i would say i'm neither a novice nor an experimented builder... the same person who gave me that amp is a local tech i've been knowing for years... and guided me to build a 5E3, mod a bassman and build several stompboxes... i like to work at his place, thus, whenever i have a question, he usually can answer it... but you're right... should be time to do it on my own.... since he will soon retire...

anyway, thanx

juju
What a great resource! Your current circumstances probably forbid, but you ought to apprentice to him then take over the business!
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ApexJr.
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Re: mystery triad output transformer

Post by ApexJr. »

I would salvage this amp and redo it to equal the MC 40

McIntosh Tube Amps are very desireable in the real world
Check HIGH retail prices at Audio Clasics.com in New York

It looks in great shape and will be worth more as a MC 40
than as parts...

Steve @ Apex Jr.
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skyboltone
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Re: mystery triad output transformer

Post by skyboltone »

ApexJr. wrote:I would salvage this amp and redo it to equal the MC 40

McIntosh Tube Amps are very desireable in the real world
Check HIGH retail prices at Audio Clasics.com in New York

It looks in great shape and will be worth more as a MC 40
than as parts...

Steve @ Apex Jr.
Hey Steve. I almost made that mistake too. Scroll further down to the auditory testing record player in the middle of the page.
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tele_player
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Re: mystery triad output transformer

Post by tele_player »

That McIntosh, and all the schematics, show 6L6 tubes, not 6V6 as mentioned in the first post.

Do the amps have the McIntosh-style chassis, as in the top photo? I'm pretty sure they do...

Those amps are worth a lot of money, I would definitely not gut them for parts.
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skyboltone
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Re: mystery triad output transformer

Post by skyboltone »

There just ain't nobody paying attention I guess. HE'S NOT TALKING ABOUT THE MCINTOSH!!!!! HE'S TALKING ABOUT THE HEARING TEST MACHINE!

Sorry just trying to help

Dan
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tele_player
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Re: mystery triad output transformer

Post by tele_player »

Dan, you're right - I mis-read that page a few times before I finally got it... :)
jujudubluz
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Re: mystery triad output transformer

Post by jujudubluz »

There just ain't nobody paying attention I guess. HE'S NOT TALKING ABOUT THE MCINTOSH!!!!! HE'S TALKING ABOUT THE HEARING TEST MACHINE!

Sorry just trying to help

Dan
right


juju :)
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Phil_S
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Re: mystery triad output transformer

Post by Phil_S »

An unknown OT is relatively easy to figure out. Find an AC wall wart (most put out DC) or tap the filament supply from a regular PT for a source of low voltage input. Instructions are here:
http://www.radioremembered.org/outimp.htm
You already know the application and the tubes, so once you know the turns ratio, you really have just about everything you would need to know about it.
jujudubluz
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Re: mystery triad output transformer

Post by jujudubluz »

hey

thanx a lot for the tip

juju
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