OT for quad EL84 amp

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flintrock
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OT for quad EL84 amp

Post by flintrock »

Hey all. I am converting an old Magnavox chassis to a guitar amp. It uses 4 el84's, and 2 12ax7's. It was a stereo amp with two Output trannies, which have been removed for a single OT. I'd like to wire it up to Orange specs, maybe an AD30 or similair . What specs would I be looking for or is there one you would recommend?
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martin manning
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Re: OT for quad EL84 amp

Post by martin manning »

You could parallel the two original OT's and mismatch the secondary to run 4x EL84.
Last edited by martin manning on Wed Jan 01, 2014 7:12 pm, edited 2 times in total.
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The New Steve H
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Re: OT for quad EL84 amp

Post by The New Steve H »

I don't know the first thing about Orange amps, but I just made a 4-EL84 amp that sounds fantastic, and I used a Classictone 40-18064.
Relax. It's SUPPOSED to smoke a little.
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M Fowler
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Re: OT for quad EL84 amp

Post by M Fowler »

For 4 EL84's most likely Orange used 4k primary OT.
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Re: OT for quad EL84 amp

Post by flintrock »

That's a great deal on that Classic Tone! Just might be the ticket. Its a 6.6k.
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M Fowler
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Re: OT for quad EL84 amp

Post by M Fowler »

That is the Trainwreck Express transformer I would get something else.
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martin manning
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Re: OT for quad EL84 amp

Post by martin manning »

I agree with Mark it'd be better with a 4k Zaa... Classic Tone 18-049 (AC30 OT) $76.
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M Fowler
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Re: OT for quad EL84 amp

Post by M Fowler »

I agree with Martin that AC30 is great.

The 40-18020 HRD 40W is 4k2.
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martin manning
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Re: OT for quad EL84 amp

Post by martin manning »

M Fowler wrote:The 40-18020 HRD 40W is 4k2.
And cheap, too!
flintrock
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Re: OT for quad EL84 amp

Post by flintrock »

Thanks guys, I'll get the AC30 one.
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flintrock
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Re: OT for quad EL84 amp

Post by flintrock »

Too bad the HRD model has no 16 ohm tap...all my cabs are 16. It's a much nicer price.
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M Fowler
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Re: OT for quad EL84 amp

Post by M Fowler »

If your cabs are 212 you could wire them to see 8 ohms.
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Cantplay
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Re: OT for quad EL84 amp

Post by Cantplay »

No you can't.

If its a 212 at 16 ohms its 2 8 ohm drivers.

Parallel gives you 4, series gives you 16.

Unless you mean wire 2 cabs parallel.

John
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M Fowler
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Re: OT for quad EL84 amp

Post by M Fowler »

Cantplay wrote:No you can't.

If its a 212 at 16 ohms its 2 8 ohm drivers.

Parallel gives you 4, series gives you 16.

Unless you mean wire 2 cabs parallel.

John
Yeah your correct my bad I was thinking one could wire it for 16 ohms.

Probably why I never buy 16 ohms speakers if I can help it.

http://www.eminence.com/support/wiring-diagrams/ :)

If he has two 8 ohm speakers then he should run them parallel for 8 ohm load not 16.
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cbass
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Re: OT for quad EL84 amp

Post by cbass »

I think mark meant 4 ohms in parallel
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