[FEDEFEDE]

Hi,

http://s778.photobucket.com/albums/yy63/FEDEFEDE1/

The structure is non-magnetic stainless steel filled with sound absorbent
The tweeter is suspended with two opposing neodymium magnets to dampen the vibrations. you can move forward or backward to adjust the offset
The woofer's pendulum is damped with two magnets in attraction. The damping is adjustable with the steel cylinder. moving the magnet on the structure is possible to adjust the angle of the woofer
The plexiglass panel is 6mm, it is not in contact with the woofer and even with the floor. The panel does not vibrate also because its thickness is always within the thickness of the basket of the woofer (10mm)

The box of the high-pass crossover is separated, there is only one bridge to provide a counterweight to the steel structure.
The capacitors are Mundorf Silver / Gold and the resistors are Duellund.
The components are all on damping material.

... sounds good!

[Russell Dawkins]

A breath of fresh air.

Congratulations! Beautiful execution.

[Don_S]

Interesting and attractive design. Thank you for posting. Where did you get the inspiration?

And welcome to Audio Circle. 

[Hebrew Hammer]

no joking here.. there is truly something magical with not having a baffle... truly colorless playback..

and great use of plexi with the woofer!!!

you did a bang up job!!!

[mcgsxr]

Welcome to AC, and more specifically welcome to the Open Baffle Circle.

I must have missed the joke, that is one cool OB install!

Thanks for sharing.   

[Rudolf]

Very transparent construction. I like the driver suspension by magnets - really ingenious. Can you tell more about the considerations leading to the disk in front of the woofer?

[FEDEFEDE]

Thank you all for comments! 

My inspiration is the simplicity.

the disk in front of the woofer:

acts as mechanical low-pass
reduces the breakups
corrects the directive to make it similar to the directive of tweeter
provides a front loading for the supravox membrane (hereupon boosts the bass)

the disk was designed by a friend of another forum.

[Rudolf]

the disk in front of the woofer:

acts as mechanical low-pass
reduces the breakups
corrects the directive to make it similar to the directive of tweeter
provides a front loading for the supravox membrane (hereupon boosts the bass)

Those are bold statements. I can follow the low-pass and the front-loading argument. Are there any measurements or other proofs/impressions as to what extent the other goals have been reached?

Rudolf

[djn]

Those look magnificent.  Now I know what I can do with my Heils.  How do they sound???

[FEDEFEDE]

Rudolf sorry, but I'm not able to provide technical data on the mechanical low-pass, it was designed by a friend of another forum. I will not say things are not accurate.


What I can say is that this type of acoustic solutions (not electric) give very good results. It 's a way to study.

About reducing the break-up I can show you a SIMILAR thing:

http://www.caninialtoparlanti.it/nocrossover_.htm

Figure 5 and 10 (electric Crossover ) and Figure 6 and 9 (mechanical crossover)

About the directivity correction I think it's important the phenomenon of diffraction.

I am not able to say more.   

[Rudolf]

FEDEFEDE,
thanks for the link. I'll dive into it with babelfish 

[FEDEFEDE]

Have a good trip !!! 

[panomaniac]

Thanks for the link to the paper.  Google does a good job translating it.
Acoustic lenses have been around for a long time, of course, but this one looks interesting and certainly his plots are good.  Distortion plot looks too good to be true.

I've tried similar diffusers made from felt in front of fullrange speakers with some success.   It's something worth playing around with.

[Bob in St. Louis]

Most interesting. Very intriguing design I must say. Welcome to AC!

Bob