Bell & Howell Filmosound 385 Projector Amp

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Bell & Howell Filmosound 385 Projector Amp

Postby (Dom) » Mon Aug 07, 2017 4:35 pm

I scored a complete Bell & Howell 385 Filmosound Specialist projector at the swap meet last weekend. Amazing 1950's build quality. Under the 16 mm projector it has an 18 watt tube amp with 2 6v6's, 2 12ax7's, a 5y3 & a 5879. The Schumacher transformer dates to late June of 1956. The original power cord is missing. I have to wire up a 3 wire cord and swap the output jacks to standard 1/4 inch then the fun task of slowly bringing it up to power. Everything looks completely mint inside, no visible leaks from the caps. It is a rats nest for sure but honestly, I've built pedals with waaay less space inside. I've never worked on tube amps so it will be slow, careful going. I saw one built with a tremolo circuit in place of the projector exciter.

I've been intrigued about these Filmosound conversions for several years. Blake Mills uses them if you are curious about the sound although his are not stock. I always thought it would be fitting to play one since I have a TV/Film degree. They sound great cranked, have a unique tone and have the touch sensitive tube dynamics I've searched for. Cleans up by lowering your volume or pick attack, like it should be. The redone ones are out of my price range along with everything else & I never thought I'd find one.
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Re: Bell & Howell Filmosound 385 Projector Amp

Postby (jps) » Mon Aug 07, 2017 5:57 pm

You need to play this through the projector! :mrgreen:



https://www.youtube.com/watch?v=uwhxc3OCBjc
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Re: Bell & Howell Filmosound 385 Projector Amp

Postby (Dom) » Mon Aug 07, 2017 8:39 pm

Ha ha! I actually did a couple shows playing guitar synth to silent movies in college...on a Rickenbacker!

I have considered one of those new projector phones to stick in the amp at shows as a joke.
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Re: Bell & Howell Filmosound 385 Projector Amp

Postby (jps) » Mon Aug 07, 2017 9:24 pm

Projector phone?
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Re: Bell & Howell Filmosound 385 Projector Amp

Postby (Dom) » Mon Aug 07, 2017 9:57 pm

Yup, we've gone from this beast to now being able to project images using a cell phone.
Image
The belly of the beast
Image
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Re: Bell & Howell Filmosound 385 Projector Amp

Postby (jps) » Tue Aug 08, 2017 1:15 am

Looks like your Photobucket account is closed or needs a major upgrading, or something.
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Re: Bell & Howell Filmosound 385 Projector Amp

Postby (Dom) » Thu Aug 10, 2017 1:47 am

jps wrote:Looks like your Photobucket account is closed or needs a major upgrading, or something.


No, it's merely Photobucket blatantly committing extortion...from free hosting to holding images hostage for a $400 ransom.
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Re: Bell & Howell Filmosound 385 Projector Amp

Postby (soundmasterg) » Mon Aug 14, 2017 8:03 pm

Dom wrote:I scored a complete Bell & Howell 385 Filmosound Specialist projector at the swap meet last weekend. Amazing 1950's build quality. Under the 16 mm projector it has an 18 watt tube amp with 2 6v6's, 2 12ax7's, a 5y3 & a 5879. The Schumacher transformer dates to late June of 1956. The original power cord is missing. I have to wire up a 3 wire cord and swap the output jacks to standard 1/4 inch then the fun task of slowly bringing it up to power. Everything looks completely mint inside, no visible leaks from the caps. It is a rats nest for sure but honestly, I've built pedals with waaay less space inside. I've never worked on tube amps so it will be slow, careful going. I saw one built with a tremolo circuit in place of the projector exciter.

I've been intrigued about these Filmosound conversions for several years. Blake Mills uses them if you are curious about the sound although his are not stock. I always thought it would be fitting to play one since I have a TV/Film degree. They sound great cranked, have a unique tone and have the touch sensitive tube dynamics I've searched for. Cleans up by lowering your volume or pick attack, like it should be. The redone ones are out of my price range along with everything else & I never thought I'd find one.


Sounds like a cool project! Please follow proper safety procedures! If you are working with a live amp, the rule is only one hand at a time, so that you don't get shocked. Its not a hard rule if you know what you are doing, but until you are completely aware, then it is a good rule to follow. Don't work on a live amp with any distractions around. Keep other's and your hands away until you are certain caps have been drained of their voltages. Observe the polarities with the electrolytic caps when you replace them or you will get exploding caps.

Make sure you wire up the 3 wire power cord properly. If in the USA, black goes from the wall to the fuse, then to the switch, then to the transformer. White goes to the other side of the transformer directly, and green goes to the chassis on it's own chassis bolt, secured with a keps nut, and leave a little slack on the green wire so that if the cord is pulled out, it is the last one to lose connection. Do not put the green wire to the chassis on a transformer bolt!

Replace all of the electrolytic caps, even if no visible signs of leakage. The paste in them fails over time, especially with non-use. Replace any selenium rectifiers with a silicon diode if there are any in the amp, test any of the coupling caps with operating voltages to see if they leak, or just replace them with modern caps such as Mallory 150. Clean the pots and jacks and sockets with Deoxit 5 or similar. Check and replace any resistors that are out of tolerance too.

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Re: Bell & Howell Filmosound 385 Projector Amp

Postby (jps) » Mon Aug 14, 2017 8:43 pm

soundmasterg wrote:Sounds like a cool project!...

Well, it should be, given this is a projector. :mrgreen:
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