Richard Allan "Bafflette" volume pot.

[hififan]

Hi,

I was given this Vintage Richard Allan "Bafflette" type C875.

It seems in good order except that the volume pot had come loose and someone has been twisting it and broken some of the posts.

I'd like to replace it and get the unit operational again. Can anyone advise me where I might find one or a suitable replacement.

Thanks

[paulsherwin]

That isn't a pot. It looks more like a switch. Does it just turn the speaker on and off?

[barrymagrec]

Multi position constant impedance attenuator.

[hififan]

Thanks for your speedy replies and for demonstrating my ignorance immediately.

So, what does it do? Is it a volume control or is it for variable impedance inputs.

The back cover states that it is a low impedance unit.

Same question applies, does anyone know where I can find a replacement?

Thanks

[paulsherwin]

Assuming Barry is right, it's basically a switched volume control. The idea is to present a constant load to the amplifier (probably about 3 ohms) while providing different levels of attenuation. This was important with valve amplifiers.

You don't need the switch at all to use it as a simple extension speaker. Just connect the signal to the speaker terminals.

Back in the 50s radios were expensive, and people would often only have one in the living room. It was quite common to add an extension speaker in the dining room so that people could listen to Two-way Family Favourites while eating their Sunday roasts.

[hififan]

Thanks Paul. I was hoping that I could just put it back as it was but I guess the simple thing is to just put the attenuator back in place and wire the speaker direct.

[barrymagrec]

These kind of extension speakers were quite common in the old days - we had a stentorian version, commonly used to provide radio in the kitchen when the main set was next door in the sitting room. The volume control was normally a 4 or five position switch, normally without detent and wired with some resistance coils to make an attempt at constant impedance.

You can see the remains of these resistors in the picture of the Richard Allan unit.

[paulsherwin]

Originally Posted by hififan

Thanks Paul. I was hoping that I could just put it back as it was but I guess the simple thing is to just put the attenuator back in place and wire the speaker direct.

There's no reason why you shouldn't simply rebuild the switch arrangement with some low value resistors. You just need to find out the required values, buy them and solder them in place. It may be more trouble than it's worth though.

[hififan]

Thanks again Paul but I think the rebuild would be a little beyond me. A couple of the posts are snapped off. I have already bypassed it. It is a pity. There was no toothed washer so I presume someone has twisted the knob and the whole unit has turned twisting up the wires and damaging it. Ultimately it is probably better as it is now just as an extension speaker.

[Diabolical Artificer]

I have some proper pots for this job, it's a volume control and 8 ohm load in one control, if you want one drop us a PM, yours for the postage.

Andy.

[RojDW48]

I had one of those for a while - very nice little thing. Mine was orientated vertically. The auctioneer must have described it from a photo alone - it was described as a radiogram.

[paulsherwin]

Corner units like that were very popular as home woodworking projects in the 50s. I have one, made by an uncle in his shed. It has a lamp in the top with a frosted glass cover. Sadly it sounds a bit grim, though I keep meaning to fit a better speaker at some stage.

[Herald1360]

Originally Posted by RojDW48

I had one of those for a while - very nice little thing. Mine was orientated vertically. The auctioneer must have described it from a photo alone - it was described as a radiogram.

Having the word "console" on the back may not have helped a cataloguer unfamiliar with old audio equipment......