Eiron wrote:

What enclosures and room do you have?
B139s need an enormous box to get decent bass.

The enclosures are the remains of the home-brews I acquired many years ago.
They're based on the KefKit3 - Concerto drivers, crossover and baffle, build
yer own boxes. About 14" deep, 2' wide, 3' high. I once calculated the
volume to be 135L. They also have a series of slots cut in the back (by the
original builder), which I think is probably a bad thing. The main speakers
are Kef Q Compacts, so the mid and top drivers in the old boxes are now
unused - they're just big reflex bass cabs, probably with added slotty mush.

The room is concrete all round apart from the ceiling, about 6x4.5m, but
with a plasterboard-walled kitchen in one corner. L-shaped in other words,
with the kitchen door permanently open. Thin carpet on the floor, big thick
rug on top, comfy couch, venetian blinds on the wide window behind. I have
plans for heavy curtains and would like to find something to put behind my
oil paintings to try and damp the walls somehow. They're quite big
paintings - 1m x 0.8m, and there's about 18mm of space behind the canvas due
to the woody things it's fitted to. They strike me as a handy place to put
some clever sound deadening panels, but I have no idea what to go for.

The long term plan for the bass speakers, when I can be arsed to get around
to it, is to rebox them in IB enclosures of around 40L, but as isobarics (I
have a second pair of drivers in a cupboard somewhere). The isobaric set up
doubles the power in the coil for a given volume and cone area, so the 40L
shouldn't be a restriction (roughly equivalent to a single driver in an 80L
cab).

Since the system is tri-amped, I shouldn't have any trouble with impedance
differences between bass and mid/top (just adjust the volume control on the
bass amp, then forget about it). I'm hoping for a cleaner, tighter bass
sound, and the ability to stay controlled at higher volumes.


--
Wally
www.wally.myby.co.uk
You're unique - just like everybody else.