I really thought I had reached end-game with this design until I was contacted by Jerome in France to show me his take with his 'minimalist' frames....
I was immediately struck by the simplicity & compactness of this design and set about to duplicate it.
To summarise the relevant speaker stands I had been through in my journey:
The original brief was to hang the clamshell woofer arrangement by the magnets hammock style, the rational being to reduce the vibrations getting into the frame & floor. It was quite effective in this regard.
I lived with this arrangement for years. Then when I replaced the Open Baffle top speakers for boxed bookshelf, I lowered the crossover point from 250hz to 60hz. I recently decided to couple to the floor using rigid stands. I used a 'cradle frame' arrangement for this which was an adaptation of my original wooden cradle frame:
but still using the metal scaffold arrangement:
This brought my wooden floor into play and became seismic with low bass frequencies, so much so I had to rebalance the bass volume by a couple of notches.
To create Jerome's design, I had to lose the metal frame completely and use the clamshell assembly itself as a stand to support the bookshelf speakers. I just needed to keeps the woofers stable on the floor below the chassis with a couple of footers, and incorporate a shelf above the chassis to mount the bookshelves to. I did this using some 40mm hardwood kitchen worktop cut to shape and bolted to the original holes in the chassis:
.....and final result:
Bass with this method was not as seismic as with the metal frames so I could increase bass by a notch. I think the balance with the floor is more controlled now. For those of you that may be concerned about vibrations getting through to the bookshelves, they are decoupled using these anti-vibration bobbins:
Luckily, the base of the Focal Shapes have M6 threaded inserts which these will fit right into.
The stand is very stable, but with all the floor coupled stand arrangements using the UM18's, the bases need to be stuck to the floor or they tend to wander. I just used some double sided carpet tape and this seems to be effective.
Very pleased with this final design which is stable, cheap & easy to make, plus pleasing on the eye. Thanks Jerome!
