Hi all,, I'm looking into an overseas Bell & Howell projector, with amp & speaker, & the speaker output of the amp has 4 prongs, 2 vertical, 2 horizontal. Is the Cinch Jones adapter what I will need to convert it to a modern day +/- 1/4"?Thanks all, & be well.
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There was a similar adapter for the Quad II amplifier, I think for the RCA socket.
I would ohm it out first, but you could rewire the original socket, if necessary.
Or drill a hole for a phone jack somewhere close by, and wire it in parallel.
I would ohm it out first, but you could rewire the original socket, if necessary.
Or drill a hole for a phone jack somewhere close by, and wire it in parallel.
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A modern day speaker out would be a Speakon connector. Press-fit (AVR Amp) for a cheaper version.
1/4" jacks are obsolete by modern days. I remember seeing them on "Community" speaker cabs 30 years ago.
First check how many of those connector pins are actually used.
There must be a reason they used FOUR of them; wouldn´t be surprised AT ALL for two being actual speaker out and other two for something necessary, maybe some kind of Mute, field coil , preamp standby, etc.
Please state exact model and search for its schematic or user manual.
"Obsolete"? 😕
A zillion current amps and cabinets keep them very much alive and in fact would be perfect in that projector and its accompanying speaker.
Thnx all,,, it's a Great Britain Bell & Howell model 631 amp. Obsolescence? It's a simple P.A. being modded for guitar,,, I can't find the schematic nor the B&H database I once frequented.
Peace all~
Peace all~
Ok, open the chassis and check how many pins are wired and where their wiresn go.
A picture could help.
A picture could help.
Speakons may be the happening connector today, but there are still TOOOOOONS of 1/4" connectors in use for speakers.
On some later models Bell and Howell used .206" diameter phone plugs. Also seen them used for aviation headsets. However not quite compatable with the smaller size patch bays.
I do not recall ever seeing any Jones plugs or similar. (Jones was bought by Cinch so if you want to pretend to be old you call them Jones! Also the original plugs used the same spacing as U.S. AC outlets!)
I do not recall ever seeing any Jones plugs or similar. (Jones was bought by Cinch so if you want to pretend to be old you call them Jones! Also the original plugs used the same spacing as U.S. AC outlets!)
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is this the unit in question Bell & Howell 16mm Projector Model 631 << Trans Asian American Film & Cinema
Yeah, that's it, but not from that seller. All it is is the little red chassis beneath the camera,, none of the other stuff,,, but I want a schematic so my tech can do his magic!! I used to have a site saved with EVERY B&H chassis made... it's hiding somewhere on my phone, but I've given up looking, but even with my superb searching skills, I got a whole lotta nuthin'...
Be well, Kenny
Be well, Kenny
Me too.
As in 99% of Musical Instrument amplifiers and cabinets except those >150 or 200W, or PA cabinets (which fit the first parameter, of course) which are the remaining 1%
Based on field observations.
And I have NOT seen Hi Fi or Home Video or Car Audio equipment using Speakons either.
The problem here is current (Amperes). I don't know 1/4 jack current specs, but with current hungry power amps needing more than say 6A, they won't last long.
There is always the problem of shorting the amps when inserting jacks powered on.
There is always the problem of shorting the amps when inserting jacks powered on.
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True, I HATE Plugs as connectors.
But that does not change the fact that they are the most used connector in the MI world , by far.
As of high current specs, for decades 100W into 4 or 8 ohm was the practical limit, whatever you could get from 4 6L6/EL34 power tubes, think Fender Twin, Marshall Plexi, Sunn, Hiwatt, Orange, Ampeg V4 and practically everybody else.
SS amps changed the landscape, of course, modern Class D ones even more, and these brought the Speakon to wide use in high power units, but Musicians are VERY conservative to put it mildly so we will have the 6.35mm plug/jack well into the future.
FWIW some used specially reinforced jacks to cope while maintaining the old standard.
I´ll show you my own 🙂
Center is the typical generic jack you can buy anywhere over the counter, I show a Stereo one because that was the inspiration for mine, notice thin metal used for contacts. And the cheap ones just use nickel plated iron 😱
Right is the current most popular, the "Marshall/British/Cinch type" , again thin metal although good ones are made of plated phosphor bronze.
Left is mine.
Custom made (I had to order 1000), *double positive contact*, notice both are same length and grab tip from both sides, and to boot made out of triple thickness spring temper phosphor bronze.
I have to instruct users about them because it´s hard to insert plug and even harder to pull it away (I had a problem of high power Bass cabinets "spitting" the plug out 😱 )
Also notice enlarged terminal holes to admit thicker wire.
But that does not change the fact that they are the most used connector in the MI world , by far.
As of high current specs, for decades 100W into 4 or 8 ohm was the practical limit, whatever you could get from 4 6L6/EL34 power tubes, think Fender Twin, Marshall Plexi, Sunn, Hiwatt, Orange, Ampeg V4 and practically everybody else.
SS amps changed the landscape, of course, modern Class D ones even more, and these brought the Speakon to wide use in high power units, but Musicians are VERY conservative to put it mildly so we will have the 6.35mm plug/jack well into the future.
FWIW some used specially reinforced jacks to cope while maintaining the old standard.
I´ll show you my own 🙂
Center is the typical generic jack you can buy anywhere over the counter, I show a Stereo one because that was the inspiration for mine, notice thin metal used for contacts. And the cheap ones just use nickel plated iron 😱
Right is the current most popular, the "Marshall/British/Cinch type" , again thin metal although good ones are made of plated phosphor bronze.
Left is mine.
Custom made (I had to order 1000), *double positive contact*, notice both are same length and grab tip from both sides, and to boot made out of triple thickness spring temper phosphor bronze.
I have to instruct users about them because it´s hard to insert plug and even harder to pull it away (I had a problem of high power Bass cabinets "spitting" the plug out 😱 )
Also notice enlarged terminal holes to admit thicker wire.
Attachments
The amp in *this* thread seems to be a UL84 team (same as EL84, say 18 Watts). Many thousands of 10W-50W amps of all impedances have run 1/4" jacks. Aside from dirt and cheap springing, they work fine.
The connections in a SwitchCraft 1/4" are really closer to a US type 15A plug than say a USB 0.5A rating. And even headbanger musicians do not hold FULL power ALL night long.
The 1/4" is the obvious change for an amp in this class.
EDIT.... Early Ampeg SVT (300W) have EXT SP at 150W 4 Ohms, so 6 Amps. The Fender 400ps has *three* 1/4" jacks at 145W 4r each (again 6A).
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