In message , Stewart
Pinkerton writes
IIRC, the driver was at the fireplace end, the chimney being used as a
B&W style tapered transmission line, rather than a horn. But it was a
long time ago, late '60s or early '70s I think.

Worked well with glass-fibre loft insulation stuffed up the chimney to
damp the resonances. A good location for a proper bass woofer if you
still happen to have the right chimney.

I've even got the ideal Goodmans Audiom 81 to use for it to keep it all
early-70s style! (As well as four Goodmans 301s for when I finally can
afford to buy a barn!)
--
Chris Morriss