HiFi Subjectivist ¦ Audio Forum ¦ NVA User Group

I think this idea is deserving of its own thread...

jimbob wrote: ↑Tue Jun 11, 2019 6:12 pm I’m thinking 355mm mdpe gas pipe. Wall thickness of approximately 20mm. Capped off at the bottom with 25mm plywood. A plywood insert at the top with a cut out for the bass driver. I haven’t decided on the length of the tube yet. A hole cut in the front for the tweeter and one in the side for the midrange.

I came up with a cylinder idea and doc poo pooed it. Said he had tried it and was awful.

Anyway cutting holes in cylinders is not easy.

jimbob wrote: ↑Tue Jun 11, 2019 5:33 pm Have you heard the bbcube to determine how that affects the midrange driver?

I haven't heard the BBC's only my version of it with mid in it's own box.

jimbob wrote: ↑Tue Jun 11, 2019 6:07 pm Also, how cube does the cube have to be? I’m pretty sure an upward firing driver would also work in a rectangular box too??

I tried the 12 inchers in a marantz cab and the bass was overblown on certain cd's with very low bass (Portishead, Jamiroquai etc). The driver was in the front baffle and right at the bottom. Cab was not so deep and quite high. Volume about 45L. I was going to try a clamshell isobaric arrangement with those cabs but never got round to it.

Soon as i made a cube of eighty odd litres it was fine. When i turned those into isobaric i simply divided the enclosure into two equal parts. So the drivers are no longer loaded by a cube but a cube cut in half. There are no problems with this arrangement, in fact they are amazing. Without a doubt the most pleasing speakers i have ever heard.

Interesting... if I can get the mdpe tube for a reasonable enough price then I will give it a go anyway, just to scratch the itch! I would really like to hear some isobaric speakers to see what the fuss is about

I've come to the conclusion that 2 bass drivers on the front baffle are better than isobarik configuration, but I await your findings with interest.

Dan, what is it that you prefer about two front baffle mounted speakers?

More of everything. 2 doped bass drivers in series. I love the way it sounds.

Currently, I'm using celestion Ditton speaker boxes, but I have a sneaking suspicion that deeper boxes would be better.

Do you prefer the presentation of point and squirt over semi omni regardless of the number of drivers?

I think some custom built boxes would give you improvements.

I've got Bay windows and high ceilings, both mitigate against omnidirectional.

Also, only I listen in a particular seat, so again omnis are mitigated