Personally when viewing the aesthetics, I marginally prefer the look of the second drawing with the splayed legs which attach to the timber which the down firing mid bass is mounted in. Nobody else seems to have a view on it. Maybe I am boring you all. The arrangement in the first drawing is easier ...

I can well believe that story Geoff. I have tried to preserve these high frequencies even though I can't hear them. NVA amplifiers have a low pass filter at the input with a corner frequency which is higher than most.

Interesting story Rex. Luckily (or unluckily) my heavily doped drivers are nof particularly sensitive. Unless a problem becomes audible I will be in blissful ignorance :grin: At the moment I don't have any audible problem when changing volume. Mostly because I can't change volume :lol: due to having...

Where have you been the last two years ?

Either design has a high centre of gravity, you need to ensure that it will remain inside the footprint of the speakers. The wider the spacing of the feet the more stable the speaker. Thanks Geoff. I did realise that. I could make the legs from solid round brass bar as I have a load of it. That wil...

This will illustrate the two options I have. I have reduced the size of the mid bass sphere to 30cm diameter. Both drawings are to scale. Option one with three legs connecting to three equidistant tabs which stick out from the 21mm ply dividing band. Legs shown are 1" round but not tapered. htt...

Geoff.R.G wrote: ↑Sun Jun 27, 2021 1:44 pm

karatestu wrote: ↑Sun Jun 27, 2021 1:14 pm The three legs would need to be perpendicular to the floor rather than splayed outwards.

Why? You could have splayed legs attached to the plywood rings.

Well they could be splayed but the speaker footprint might be getting a bit wide.

Wonfor14 wrote: ↑Sun Jun 27, 2021 12:58 pm I used this with a large SECA (Class A) but the main amp had is O/P connected to the PSU so the PSU tracked the amp, not dissimilar to Class G but A/G maybe mm. and it worked very well.

Does this psu have massive dynamics by any chance ?

Thought I better do some thorough volume calculations for the mid bass sphere as that is very important for bass response. For a sealed box there is some leeway unlike ported. Through experimenting I found the ideal volume for two of the doped 5.25 inchers to be 13 Litres minus the volume of driver ...