project ideas 6l6s and octal pre-amp

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menger66
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project ideas 6l6s and octal pre-amp

Post by menger66 »

I have a old movie projector amp chassis ive stripped and am prepping to build something into, Amp used 6l6 powertubes and 6sq7 and 6sl7 pre-amp tubes, what amps should i check out clips for build ideas? thanks mark
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M Fowler
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Re: project ideas 6l6s and octal pre-amp

Post by M Fowler »

Ampeg B15N but for guitar use 6SL7, 6SN7, 6L6, 6L6, 5U4 very bluesy but powerful even at 25w.

Fender 5b6 6SC7, 6SL7, 6L6, 6L6, 5U4 very good for jazz, blues, I actually rock out with mine because it takes pedals so well about 25w.

Mark
menger66
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Re: project ideas 6l6s and octal pre-amp

Post by menger66 »

I was just looking at the 5b6, but was thinking about using a 12ax7 pi im sure thats been done? Thanks mark
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M Fowler
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Re: project ideas 6l6s and octal pre-amp

Post by M Fowler »

Yeah you could use a 12AX7 in the PI or 12AT7.

This Weber 5C3P is very close to the 5b6 you can use for reference.
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menger66
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Re: project ideas 6l6s and octal pre-amp

Post by menger66 »

That's cool thanks mark, Im gonna give it some thought i'm leaning towards using the octals just for something new i have not tried before, The chassis setup perfectly for PTP build and it looks like to much fun not to give it a try, The PT is massive and im gonna try some 6550 in it for kicks :D mark
billc
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Re: project ideas 6l6s and octal pre-amp

Post by billc »

I recently built something similar from an old PA amp, went with a Gibson GA-20 (6SJ7, 6SL7, 2x 6V6, 5Y3) as that is the sort of tone I want...a 40's/50's jazz/blues sound and it does that very well. Anyway I used a 6SL7 for the PI and it works great, also stuck with point-to point wiring and really enjoyed the challenge of making that work, did add one terminal strip along the way...
have a tube socket left and was going to wire it as a GA-20 mic channel but after reading this thread think I'll try a 6SC7 like an old Bassman or Pro, have some NOS ones and they are in a metal can so that will help with hum and noise...will also try running the triodes in parallel
Last edited by billc on Sat May 03, 2014 6:43 pm, edited 3 times in total.
passfan
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Re: project ideas 6l6s and octal pre-amp

Post by passfan »

I've built both the Rocket and the Express using octals. Hard to imagine they could sound even better.
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menger66
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Re: project ideas 6l6s and octal pre-amp

Post by menger66 »

I have extra holes in my chassis and could use 3 pre-amp tubes for just about any old TV front fenders, Its seems like those amps are pretty much the same basic design with extra inputs and thats not really a feature i care about. I guess i need to spend a couple hours listening to clips, including some gibson amps, My chassis has a tube socket thats sunk into the chassis maybe it's to help with pre-amp noise im not sure chassis is 6 x 16 x 1 7/8, here's a pix mark
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billc
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Re: project ideas 6l6s and octal pre-amp

Post by billc »

If you end up liking the 6SJ7 pentode sound using one is relatively easy and the metal can is a BIG help in keeping noise and hum down...though FWIW pin 1 connects to the can and needs to be grounded, this is not noted on many schematics.
I did some reading and listening myself tonight and am going to go ahead and add a 6SC7 channel to my GA-20 build, will try wiring it like a 5C3 or 5C5...hope it works out, if so having an amp that does the early '50's Fender AND Gibson tone would be very cool (and may try to set the channels up so they can be mixed too) FWIW some of the Supro's from that era are very similar to Gibson designs like the GA-20 and GA-30
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M Fowler
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Re: project ideas 6l6s and octal pre-amp

Post by M Fowler »

For true PTP the smaller the chassis the better no long wire runs. But if your going to use an eyelet or turret board that larger chassis is good.

Just my 2 cents. :)
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