Film projector amp build

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PaulWD
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Film projector amp build

Post by PaulWD »

Hi all

Inspired by this:

https://guitar.com/guides/diy-workshop/ ... on-part-1/

And a similar uncle Doug video a while ago I decided to have a crack at converting an old projector amp. I have a few kicking around.

Circuit used was an ampeg j12 without the trem. I've done a few 5e3 and model 26 fender builds and was looking for something different. Lineup is 6sl7 as pre and pi and a pair of cathode biased 6v6.
Ampeg_J12B.pdf
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I forgot to take a before pic, but it was the same as the guitar.com link above.

Sounds cleaner than a 5e3 with more headroom. I'm crap at both playing and describing sounds so I'll just bring it along to the next gearfest whenever.

The only bastard is that all projectors I've come across are 110v. I'm using an external 200va stepdown trafo.
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Re: Film projector amp build

Post by MikeC »

Very good - nice example of "point to point" wiring!
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Re: Film projector amp build

Post by Slowy »

MikeC wrote: Mon Feb 01, 2021 6:59 pm Very good - nice example of "point to point" wiring!
Looks like the insides of my Jansen 4-12
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Re: Film projector amp build

Post by MikeC »

Slowy wrote: Tue Feb 02, 2021 8:12 am
MikeC wrote: Mon Feb 01, 2021 6:59 pm Very good - nice example of "point to point" wiring!
Looks like the insides of my Jansen 4-12
Point to point always looks messy.
Last edited by MikeC on Sun Jun 20, 2021 7:15 pm, edited 2 times in total.
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Re: Film projector amp build

Post by doompalm »

Oh man, that's awesome. I love those projector amps.

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Re: Film projector amp build

Post by StrummersOfThunder »

Yesssss very cool. 10 international cool points awarded immediately.

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Re: Film projector amp build

Post by Reg18 »

He still has this amp, I played it a while back and really loved it! The only catch was the step down transformer thing. He doesn’t want a lot for it though so if your interested I’d highly recommend the tones of it if you want a review. Not that you can hear it much on this video but I used it for this fuzz demo (I guess fair to say it takes pedals well though)


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Re: Film projector amp build

Post by Molly »

MikeC wrote: Tue Feb 02, 2021 8:39 am
Slowy wrote: Tue Feb 02, 2021 8:12 am
MikeC wrote: Mon Feb 01, 2021 6:59 pm Very good - nice example of "point to point" wiring!
Looks like the insides of my Jansen 4-12
Point to point always looks messy.
Dunno. Sometimes it's a thing of beauty. I had a Tamerlane Hogee Ba Ba that was incredibly. The maker had even done that swirl-engraving on the chassis even though nobody would ever see it.

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Re: Film projector amp build

Post by Reg18 »

Molly wrote: Sun Jun 20, 2021 8:30 pm
MikeC wrote: Tue Feb 02, 2021 8:39 am
Slowy wrote: Tue Feb 02, 2021 8:12 am

Looks like the insides of my Jansen 4-12
Point to point always looks messy.
Dunno. Sometimes it's a thing of beauty. I had a Tamerlane Hogee Ba Ba that was incredibly. The maker had even done that swirl-engraving on the chassis even though nobody would ever see it.
There’s a company called Reeves Audio doing pedals that look like a surgeon put together! I aspire to get one of mine even close one day!
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Re: Film projector amp build

Post by MikeC »

Yes that pedal is very neat but it's very hard to achieve such neatness with a more complex circuit.
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Re: Film projector amp build

Post by Reg18 »

MikeC wrote: Mon Jun 21, 2021 9:44 am Yes that pedal is very neat but it's very hard to achieve such neatness with a more complex circuit.
Well I can’t get a boost pedal looking even close! And that has one pot to wire, let alone an amp with 10 or more pots!

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Re: Film projector amp build

Post by GrantB »

Molly wrote: Sun Jun 20, 2021 8:30 pm
Dunno. Sometimes it's a thing of beauty. I had a Tamerlane Hogee Ba Ba that was incredibly. The maker had even done that swirl-engraving on the chassis even though nobody would ever see it.
Wonder where that ended up? I got that from a shed in Otahuhu...the dude had this pile of what I'd call early boutique gear. Cool speakers, amps etc. He was a blues nut, trying to get the tone in his head out....
"Man is the most insane species. He worships an invisible god and destroys a visible nature. Unaware that this nature he's destroying is this god he's worshipping." - Hubert Reeves

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Re: Film projector amp build

Post by Molly »

GrantB wrote: Mon Jun 21, 2021 3:00 pm
Molly wrote: Sun Jun 20, 2021 8:30 pm
Dunno. Sometimes it's a thing of beauty. I had a Tamerlane Hogee Ba Ba that was incredibly. The maker had even done that swirl-engraving on the chassis even though nobody would ever see it.
Wonder where that ended up? I got that from a shed in Otahuhu...the dude had this pile of what I'd call early boutique gear. Cool speakers, amps etc. He was a blues nut, trying to get the tone in his head out....
Went to Jim and he flipped it.

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