40 watt ef86 pre 6L6 x2 power MV - what is it?

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xtian
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40 watt ef86 pre 6L6 x2 power MV - what is it?

Post by xtian »

I think I found my next build. I had these elements in mind, and then I stumbled across the BadCat Stella, which nails the specs: EF86 preamp, TMB stack, master volume, 6L6 PP power amp.

I have the iron, I just need a schematic. Or two. What parts can I use? Thinking about a Fender Pro Amp power section, but what about an EF86 preamp? And what kind of MV?
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LeftyStrat
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Re: 40 watt ef86 pre 6L6 x2 power MV - what is it?

Post by LeftyStrat »

The tone stack is actually switchable between a treble and bass control, and a five way switch that selects different caps. Have a look at the Matchless DC30 for inspiration on the five way switch.

Funny that you mention this configuration. I've been searching through PT's I have to do something similar.

Only I've been thinking about having the classic 5f6 tone stack for the clean channel, and maybe have it drive an EF86 for the overdrive section.

Or take inspiration from ic-racer's Manzamp build and have the topology of the 5f6, but replace the tone stack with the Skyliner tone stack.

I was thinking of using the Dynaco A470 OT. Probably the 5F6 power amp, with the ability to run both EL34's and 6L6's

Another amp for inspiration would be the Matchless Clubman.
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Re: 40 watt ef86 pre 6L6 x2 power MV - what is it?

Post by xtian »

Clubman 35 looks like a winner. 12ax7 in parallel, into a EF86, MV, pair of EL34.

Also interesting is the Dr. Z Route 66. Very simple, Vox style pre. Will this get much gain? I mean crunch?

Also, simplified AC30 channel with EF86: http://www.trinityamps.com/ForumGallery ... AC30_4.jpg
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Reeltarded
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Re: 40 watt ef86 pre 6L6 x2 power MV - what is it?

Post by Reeltarded »

Lower that 1k2 in the PI until it is about to block.. heh.
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Re: 40 watt ef86 pre 6L6 x2 power MV - what is it?

Post by LeftyStrat »

xtian wrote:Clubman 35 looks like a winner. 12ax7 in parallel, into a EF86, MV, pair of EL34.

Also interesting is the Dr. Z Route 66. Very simple, Vox style pre. Will this get much gain? I mean crunch?

Also, simplified AC30 channel with EF86: http://www.trinityamps.com/ForumGallery ... AC30_4.jpg
I like Merlin's advice of rather than running the EF86 as a high gain input stage, and dealing with microphonics, lowering the plate resistor to 100k, and using gain stages to drive the pentode, using it as tone modifier rather than a gain multiplier.
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Re: 40 watt ef86 pre 6L6 x2 power MV - what is it?

Post by Reeltarded »

I think I agree with that, but it's just a notion.
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Re: 40 watt ef86 pre 6L6 x2 power MV - what is it?

Post by LeftyStrat »

Reeltarded wrote:I think I agree with that, but it's just a notion.
Dude. Selmer. Zodiac. Twin.

:D
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Re: 40 watt ef86 pre 6L6 x2 power MV - what is it?

Post by Reeltarded »

You and Shroom all over me with this Zodiac thing! It's a case for special pleading! Lovely amp. No chance of making one that sounds like that.
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Re: 40 watt ef86 pre 6L6 x2 power MV - what is it?

Post by xtian »

Tying in this thread which has the Zodiac schemo: http://ampgarage.com/forum/viewtopic.php?p=150423

Another similar thread: http://ampgarage.com/forum/viewtopic.php?p=225354

Also reviewed Merlin's pages on small-signal pentodes (pp. 40-58, Designing Tube Preamps second ed.).
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