4- 6V6 output tranny

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dreric
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4- 6V6 output tranny

Post by dreric »

I'm considering a 4 6V6 build and I'm at a loss when it comes to a current production output transformer. The only thing I can find in the 6-8K primary range is the JTM 45 OT:

http://www.classictone.net/40-18039.html

Does anyone have any other recommendations?

Thanks

Eric
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Re: 4- 6V6 output tranny

Post by txbluesboy »

I used a 50 watt Bassman style (4K primary) in my last 4 X 6V6 build.
It sounded really good.
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ToneMerc
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Re: 4- 6V6 output tranny

Post by ToneMerc »

Half the typical two tube typical 6V6 loads, so anything from around 2.8K to 4.5K can work for four 6V6's. I used a 3.4K for my last build. Look for your typical 50W Fender or EL34 Marshall 50W type transformer.

TM
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dreric
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Re: 4- 6V6 output tranny

Post by dreric »

Thanks guys!!!!

Eric
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Re: 4- 6V6 output tranny

Post by Cliff Schecht »

I like 8k-10k for 6V6's so I'd go with 4k-6k. What ToneMerc said is spot on, I'd go find a 50W Fender job and use it. Look at a Magnetics Components 50W output transformer for Bassman's and the like with multiple output taps and M6 laminate upgrades.
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Re: 4- 6V6 output tranny

Post by ToneMerc »

Cliff Schecht wrote:I like 8k-10k for 6V6's so I'd go with 4k-6k. What ToneMerc said is spot on, I'd go find a 50W Fender job and use it. Look at a Magnetics Components 50W output transformer for Bassman's and the like with multiple output taps and M6 laminate upgrades.

That MCI 60W 4-8-16 with the M6 steel was one of the two trannies that I had on hand for my build. In the end it was toss up and chose the 50W Marshall iron with the M6 steel. It turned out well enough that I'm going to go to that well again for my next quad 6V6 build.

TM
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Re: 4- 6V6 output tranny

Post by Cliff Schecht »

Using a 60W OT here would be like using a 100W OT for a pair of 6L6s it el34s. It'll work but its overkill and won't have any benefit audio-wise.
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Re: 4- 6V6 output tranny

Post by ToneMerc »

Cliff Schecht wrote:Using a 60W OT here would be like using a 100W OT for a pair of 6L6s it el34s. It'll work but its overkill and won't have any benefit audio-wise.
I have to disagree all around with those statements, but neverthess you can easily setup a quad of 6V6's to slightly exceed 50W.

TM
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Re: 4- 6V6 output tranny

Post by Cliff Schecht »

Yah I guess it depends on the application. I don't expect much past 20W from a pair of 6V6's but you can push them past this, plus you can factor in the extra harmonics adding additional REAL output power. Maybe you're right, but I don't ask that much from my old stock 6V6's (especially the ones from WW2!).
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Re: 4- 6V6 output tranny

Post by C Moore »

ToneMerc wrote:
Cliff Schecht wrote:I like 8k-10k for 6V6's so I'd go with 4k-6k. What ToneMerc said is spot on, I'd go find a 50W Fender job and use it. Look at a Magnetics Components 50W output transformer for Bassman's and the like with multiple output taps and M6 laminate upgrades.

That MCI 60W 4-8-16 with the M6 steel was one of the two trannies that I had on hand for my build. In the end it was toss up and chose the 50W Marshall iron with the M6 steel. It turned out well enough that I'm going to go to that well again for my next quad 6V6 build.

TM
I just installed one of these in a 1968 Bassman.....its OT was dead. We also subbed in an original OT from another 1967 date code Bassman. The response seemed identical....especially in the low end. Keeping in mind.....human audio recall (which is probably poor), as fast as we could switch an OT, and leaving all the knobs set the same.....
So, switching an original OT with the M6 multi tap from MC, we could hear/feel no appreciable difference. The price is more than fair, and I was PLEASED to see the effort MC took in packing the tranny. They have been a nice outfit to deal with.
Best
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dreric
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Re: 4- 6V6 output tranny

Post by dreric »

Please forgive my ignorance.............

I'm reading that the range of acceptability would be 2.5K to 10K for a quad of 6V6.

One one end there's the marshal @ 8K

http://www.classictone.net/40-18039.html

and the other end the fender @ 4.2 K

http://www.classictone.net/40-18000.html

What is the sonic impact of higher impedance versus lower impedance in the OT?

Thanks

Eric
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Re: 4- 6V6 output tranny

Post by Roe »

higher Z will usually sound a little thiner and have less clean headroom
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ToneMerc
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Re: 4- 6V6 output tranny

Post by ToneMerc »

dreric wrote:Please forgive my ignorance.............

I'm reading that the range of acceptability would be 2.5K to 10K for a quad of 6V6.

Eric
Eric, not exactly. I'm about 100% sure that Cliff's reference(8-10K) was pertaining to a pair, not a quad of 6V6's.

Roe, is correct.

The JTM45 with KT66 at an 8K or 9K load was the best sounding mistakes ever made. However many still prefer the 6.6K combination and I prefer the 8K load only if the run at around 450 volts or so, as I find 400V with the 8K load is way too thin for me.

Again, there's many load options between 3.4K and 4.4K that you can grab right off the shelf.

http://www.classictone.net/40-18001.html M6 laminations, 4-8-16

TM
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Re: 4- 6V6 output tranny

Post by Reeltarded »

The JTM with 66s @ 9k is that angry sounding thing? The ones that sound good, an make you wonder what all the fuss is about with the others?
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Re: 4- 6V6 output tranny

Post by Roe »

most original jtm45s are 8k and around 450v, some are 6k6 though
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