Weird amp with cool looking speaker. What to do? (Pic Heavy)

[tribi9]

I bought this amp as it looked too cool to pass on. The amp is only passing a faint signal when used with a guitar. (According to the guy that sold me)

I haven't tested it myself as the first thing I did when I brought it home was to snip the AC cord.

The amp has a weird output with really thick wire coming out of one of the tubes but Im not sure what it is.

So my question.. Has anybody seen one of these? Should I turn it into a guitar amp or should I just try to restore it?

Also look at the speaker... Would this be a Jensen P12P from 1936?

[IMG:800:600]http://i114.photobucket.com/albums/n271 ... C02575.jpg[/img]

[IMG:800:600]http://i114.photobucket.com/albums/n271 ... C02574.jpg[/img]

[IMG:800:600]http://i114.photobucket.com/albums/n271 ... C02569.jpg[/img]

[IMG:800:600]http://i114.photobucket.com/albums/n271 ... C02570.jpg[/img]

[IMG:800:600]http://i114.photobucket.com/albums/n271 ... C02573.jpg[/img]

[IMG:800:600]http://i114.photobucket.com/albums/n271 ... C02578.jpg[/img]

[IMG:800:600]http://i114.photobucket.com/albums/n271 ... C02579.jpg[/img]

[IMG:800:600]http://i114.photobucket.com/albums/n271 ... C02586.jpg[/img]

[IMG:800:600]http://i114.photobucket.com/albums/n271 ... C02587.jpg[/img]

[Structo]

That's pretty cool.
I take it is a film projector amp?

Strange the speaker has a jack on it.

Is that a field coil speaker? ( no permanent magnet?)
Looks like maybe the field coil or OT was removed from the side of it.

Do you have a model number on the amp?

What are the tubes in it?

I see that Schematic Heaven doesn't list any Bell and Howell amps.

[tribi9]

Yes it is a film projector amp but there's no model # anywhere on it.

The tubes are two 6L6, one 6L7 and a 5Z4.

It looks like the magnet on the speaker is attached. It just looks like a regular alnico speaker under the cap.

The guts and all the parts inside look in pristine condition.

The only #'s anywhere are the ones on the back of the amp chassis 08951A.

According to the guy that sold it to me the speaker sounded good through an audio system but when they plugged in a guitar they just got a faint signal.

[billyz]

The Jensen is actually very good. P12 P , Alnico pretty heavy duty 25 w. But it looks like 16ohms, which is why it might sound weak in an 8 ohm amp worse even on a 4 ohm.

[tribi9]

See in this pic...


[IMG:800:600]http://i114.photobucket.com/albums/n271 ... C02574.jpg[/img]

The wire I'm talking about connects to pins 1 and 7 of the 5Z4 rectifier. Then pin 1 connects to the "To Filmosound Amplifier" and pin 7 connects to pin 6 of the 6L7.

[tribi9]

I found that that it is only a power amp. with no pre amp. this amp was designed to boost the projector audio for large audience presentations.

The speaker should be from 1956 actually.

[tribi9]

What would be a good pre-amp to use/build for this? Is there something with good cleans that would work? Something that has a layout preferably.

Cheers.

[selloutrr]

any early gibson of fender preamp should be great for this build.

[tribi9]

Any idea of any links to any fenderesque preamp schems then?n Or do you pretty much just build a regular fender amp minus the OT and the power tubes?

And Structo the PI is a 6SL7 not 6L7 as I wrote before.

[rfgordon]

If that speaker, dated 36th week of 1956, works well, it's probably worth some nice cash in that pristine condition.

It could find a nice home in an amp whose speaker was done in by the flood in Nashville, for example.

[tribi9]

Yes the speaker works well. I'm keeping it tho'

[aclempoppi]

Hi there, have you tried a line level pre amp signal from any guitar amp? I would guess the power amp is set up for a conservative- hi fi output. Art

[azatplayer]

What plate voltage are you getting with it?

[JD0x0]

no ones gonna say it

DUMBLE PREAMP!

Im guessing this amp was designed with clean output in mind, making it perfect for a dumble because they are preamp distortion amps

[tribi9]

Aclempoppi and azatplayer, I havent hooked it up yet but I will get back tonight. Im putting a 3 prong AC cord later on today.

JD is there anywhere you can point where I can get an schematic or layout of a dumble preamp section? Is there something already split or do I have to figure it out and remove the power section from an existing schematic?