Filmosound projector amps ("Bernie" amps)?

[lustandfury]

Hi I'm new here and fairly new to the vintage tube amp game all together. I read some articles about using old film projector amps as guitar amps and ended up scoring 2 Filmosound amps...one running two EL84's and one running 3 6v6's. The EL84 is actually set up with a two 1/4" outputs for 8 and 16 ohms. And plugging straight into it sounded pretty sweet! The 6v6 needs some 1/4" outputs but all the tube light up and the guts look brand new.

Has anyone had any experience with these amps? I know that a lot of the circuits and a few of the tubes are not necessary to run the amp for guitar but that's about it. I wouldn't mind figuring out what I could take away from the guts since the chassis is small and really tightly packed!

I've read Bernie Raustig (up hear in Canada...Hamilton to be exact) gained quite a reputation for modding these amps and dropping them in a open back 1X10 cab. But I've also read that the mods were very minimal and like I said the EL84 sounds pretty sweet as is. Colin Cripps plays one and I've read the guys in The Tragically Hip do as well. Here's one that sold at a local music store here in Toronto:

http://www.capsulemusic.com/retail/detail.asp?ID=3225

How would you go about getting a schematic for the amp section? Would it have been in the user manual that came with the projector originally? Or is it something you have to figure out yourself? ANy help or guidence would be greatly appreciated!
Mike

[drewl]

Funny, I was just tweaking mine yesterday!
I have a late 50's Bell & Howell filmosound projector amp, 2 Cathode biased big bottle 6L6's with a 6SL7...and an awesome 16ohm alnico speaker, In a box that looks like an old radio! it's only a power amp, so you had to drive it with a preamp.
driving it with the line out of my hotplate sounded great!

I used to use the speaker with my 73 50w Marshall. Then a few years ago I stuffed a 12ax7 wired in parallel in it to use as a stand alone amp.

It used to oscillate when cranked and was a tad noisy which I chalked up to the samll size and induced hum. I had a 12AU7 in it, to cut back noise but it sounded a little weak.

So yesterday I was bored and started tinkering with it....turns out I had positive feedback going on!
So I removed the feedback, put in a 12AX7, and damn if it doesn't sound awesome!

[lustandfury]

So did your amp not have all of the extra wiring and tubes for running the projector sound functions? Mine definitely has some tubes that I believe are not needed. And it is already set up as a fully functioning standalone with 12AX7's. Do you have any pics of yours?

[drewl]

I'll have to look for pics.
Mine is a straight up power amp to be used with projectors.
I would never had known except a coworker back in the 80's told me he saw them in the army when they had meetings etc.
It even had an internal 16ohm power resistor wired to the output jack so you could use it to drive another power amp and not fry the output tranny.

[lustandfury]

That sounds like a Garnet Herzog. Have you heard of them? It sounds like that same idea. Basically a fender champ with a load resister on the output so you can plug it directly into your amps input. I recently bought an original one off of a guy here in Toronto and it makes the best distortion unit you could ever imagine! Just a huge tube distortion from light grind to ultra saturated distortion that has light Octavia sound to it.

I also found some schematics on the web for Bell & Howell projector amps but the amp I have uses el84's but the schematics for the particular model projector I got if from show 6V6's?

[Magnatone1960]

I've got a late 50's 6V6 based Filmosound that I've been working on to convert to a guitar amp.

Don't know if you've found this site yet but it's got a huge pdf file of schematics for those amps built before the 60's and I was able to find the one I have there.

http://www.film-tech.com/warehouse/manuals/AMPS.pdf

[lustandfury]

Yeah I've seen that. The EL84 model seems to have been a rare model built in Canada to meet CSA standards so it is a different design then the 6v6 model it seems.

[drewl]

WOW!
Thanks for that site.....it's got schems of the amp I have.
Sure would've been nice to have that years ago when I was just learning all this tube amp crap!
It would have saved me alot of time trying to figure out the circuit.

As far as driving an amp with another amp: I used to drive my Bogen power amps with my '73 50w marshall.....sounded fantastic and loud as hell.
That was before I knew anything about tube amps so I had no load on the Marshall's output.....luckily I never blew it up!

[platonicbomb]

Hi there,

A friend sent me a link to your posts about your filmosound amps. I have several that I want to mod as guitar amps. Those rats nests are not easy to figure out. I'm trying to discern what sections of the wiring I can safely remove.

Also if you have insight into replacing the caps without having to find replacement cans, that would be great.

Anyone up for helping bring another filmo guitar amp into the world?

Thanks,

Moses

[Enzo]

Use the search feature here for "filmosound" and read the threads about them we already have.