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Old 3rd August 2004, 05:21 PM   #1
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Default Does anyone know this english amp ?

Hello,

here is some pictures of an amp I found in my garage ...
Apparently it's made in England, but I can't find any brand on it.
I'd really like to use it as a guitar amp but I don't know if it's possible, plus it's a 110 volt and it's 220 volt in my country.
So what do you think ?

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Old 3rd August 2004, 06:34 PM   #2
EC8010 is offline EC8010  United Kingdom
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That escutcheon with "Made in England" may be a red herring, and not original. British amplifiers tended to use either the more common Mullard valves (EL84, EL34) or GEC valves (KT series). Further, that mains connector is very strange. However, Belling-Lee (the fuseholder) is a British manufacturer, so I suppose it might have been British made for the American market...

Unfortunately, it looks rather cheaply made (small output transformer), so it's unlikely that the mains transformer has primaries that can be connected for 220V. Autotransformers are available for stepping 220V down to 110V. Other than that, I don't see why you shouldn't be able to try it as a guitar amplifier.
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Old 3rd August 2004, 06:54 PM   #3
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thank you for reply EC8010

I don't think this amp was made for american market because they use 60hz and it looks like this one has 50 c/s written on the back so it's definitely for european market.
And the main connector IS strange , if only a had a datasheet to figure out ...

Is a new transformer going to be enough to use the amp on the 220v or should I change something else ?

Do you have any clue about the impedance I should use the speaker ?
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Old 3rd August 2004, 08:48 PM   #4
EC8010 is offline EC8010  United Kingdom
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Valve amplifiers were typically made to match 4 Ohm loudspeakers (typically poorer quality) or 15 Ohm loudspeakers (superior quality). You won't damage the amplifier by using an incorrect loudspeaker, merely lose output power and increase distortion.

If I were you, I'd try the amplifier out on a variac set to 120V volts before spending any money on it. And I'd bring the voltage up to 120V quite slowly (a couple of minutes, or so). Realistically, any old valve amplifier is likely to be full of dodgy capacitors, resistors that have drifted in value, dry joints etc, etc. See if you can find someone local to help you on this.

I wondered if that mains connector was German, but I thought their mains was 220V. Good point about the 50Hz. Doesn't preclude it from working on 60Hz, mind.
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Old 4th August 2004, 07:55 AM   #5
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I'm fairly sure that the amp is from an old Bell and Howell cine projector. The 110 volt supply is because their earlier projectors were powered through and adjustable stepdown transformer. I think this was to allow adjustment for variation in mains voltages (the transformer had a voltmeter with green and red zones).
From what I remember, the amp is reasonably powerful but there's not much bass or top end. Mind you, I only ever heard it working with old cine films.
Interesting find though. I think it was one of the first 'filmosound' models.
I spent many happy afternoons at primary school watching films about geography and 'new technology' on one of these. (I think I saw my first ever sex education film on it as well!!)
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Old 4th August 2004, 08:01 AM   #6
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If you are going to use it for anything, you will need to make some modifications. The slot in the can on the right hand side of the first picture is to allow light from the optical sound stripe to shine on the valve (some sort of light dependent resistor)
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Old 4th August 2004, 08:54 AM   #7
dnsey is offline dnsey  United Kingdom
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I agree, it certainly looks like a B&H amp: the peculiar connectors were used for many years.
I believe the output is nominally 10W, but they sound a lot louder.
You could use the mic input for your guitar, with a bit of attenuation if necessary.
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Old 4th August 2004, 06:47 PM   #8
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The amplifier was probably built at Mitcheldean Gloucestershire Uk in about 1955. The factory used to make Bell and Howell projectors then started making those new fangled xerographic copiers. See http://www.schimmel.freeserve.co.uk/cine/
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Old 4th August 2004, 08:57 PM   #9
v-man is offline v-man  United Kingdom
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hello from sunny wales, uk.
i had one of these little amps hanging around in my work shop for years, and i guessed by the unusual layout that it had come from a projector set up.
anyway,onto the subject of being able to use it for a guitar.
when you take the bottom off, you will find that it is pretty crampt for space to work on it, or modify its original circuitry.also, its full of rather nasty, leaky and space hugging capacitors and other wierd but useless bits that will have definately seen better days.
anyway,i had a customer who turned out to be a harmonica player.
he asked if i could recomend a suitable amp, and knowing a bit about the type of amplification harmonica players go for, i sugested the early fender delux circuit[ 5c3] he trusted my judgment on this, and asked if i would go ahead. so my first task was to find a doner chassis that i could build the prototype in. all of a sudden that little amp was looking interesting for the first time in a long while.
anyway, to cut a long story short, i stripped out the intereior,kept the output transformer, and tube bases pots, etc,and built in the fender circuit all hard wired.i used the two secondary tappings in a paticular configuration switched, so that the amp would run clean on one position,and on the other would saturate earlier on the other. what can i say,the customer loved it.i did too.
needless to say he kept the prototype version. it just go`s to show
sometimes even the most unlikely piece of vintage audio can once again have a new lease of life.

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Old 4th August 2004, 10:31 PM   #10
dhaen is offline dhaen  Europe
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Thumbs up Great stuff!

It's really impressive to see all this "local" knowledge appearing on the forum
It really does help credit us as a serious information resource, as well as helping out the original poster.
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