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Starting on a new speaker shortly; one that combines my own quarter wave TL ideas, the ideas of Winslow Burhoe (ex of AR, Boston Acoustics, EPI among others) the Doc and Roy Allison into one speaker concept.

It is a semi-omni (sort of) that uses a little bit less of the rear wall and a bit more of the ceiling, to create the stereo soundfield.
I lashed one up a couple of weeks ago using my Flatback Banned speakers as the test beds and it worked so well I was gobsmacked at the results.

Pics will appear eventually.

Wow, another stevetheshadow speaker project

Sounds very interesting steve. Does it use your usual drivers or something new ? Crossover ?

karatestu wrote: ↑Sat Feb 17, 2018 11:13 am Wow, another stevetheshadow speaker project

Sounds very interesting steve. Does it use your usual drivers or something new ? Crossover ?

I have a spare set of Faital bass/mid and SB Acoustics tweeter, so it uses the usual driver complement. No point in reinventing the wheel, when you have a good driver combo.
Crossover should be just a capacitor, as I have doped both sets of bass/ mid units with Gorilla PVA glue.
It'll be a bit 'fifties retro looking as I have got a big sheet of maroon coloured rexine doing nothing and another piece of tygan speaker grille cloth that could be pressed into service, but I need to prototype it all first.

Direct driven doped woofers Gorilla glue, is that as good as using bison kit ?

Glad to see you got your amp grounding problems sorted over at AT. Are they back in the system again ?

Stu

Yes the valve amp is back in the system, but the NVA A20 ain't going anywhere.

karatestu wrote: ↑Sat Feb 17, 2018 12:00 pm Gorilla glue, is that as good as using bison kit ?

Probably not, but then, with Gorilla glue you don't end up high as a kite

Any pictures of how to dope the drivers? Or has it been on another thread.

The speaker prototype is finished.
Quarter wave line is mass-loaded by a 3" port, 2" deep and exits into a slot load in the base of the cabinet:

Main driver and HF fire at 120 degrees to each other.
Main driver is using the ceiling to bounce the sound downwards at the listener, whilst the tweeter fires on a gentle slope up to said listener. Main driver also uses the rear wall.

I'm well pleased with the sound quality.
As this speaker is working with some of the ideas of Winslow Burhoe, it is using the room in a slightly different way to the NVA Cube or Allison Six. The image hovers at about the same height as a standing person, which is something I was aiming for and have achieved with the design.

The design is very promising and sould scale up to use bigger drivers.
I'm looking forward to exploring thee capabilities of the room flooder.
The question with this small 6" drivered version. is - how big a room is it capable of flooding?

Transmission line damping reduced to next to nothing. Just a tiny amount at the narrow closed end and BAM!

Bit more testing with a wide range of programme.
The flooder does what it says on the tin - it floods the room. This is going to sound counter-intuitive, but by using the room effectively, the Burhoe influenced flooder appears to take the room out of the equation, you're just left with the performance.

Bass is even handed and free from boom whether one sits in the centre of the room or near corners or boundaries.