Dual, front and rear firing Acoustats

[tyu]

ML CLX bass panels is made with dual mylar layers .....Cool
thanks for the info

 

[Disco-Pete]

Disco Pete: Rob MacKinlay of ER Audio here in Australia was developing a dual layer stat panel along the principles of what you have jerry rigged with your Model 3 set up. He told me at the time it had great potential to strengthen the sound field of stats and give a positive result in the manner you are describing with yours. Not sure Rob proceeded with the concept though? It was a few years ago we discussed all of this ...

Cheers,

Steve.

I think what may be a factor is that the rear firing panels are powered separately.

 

[Disco-Pete]

Well, after extensive listening, I've come to the conclusion that in this particular experiment, the Monitor 3 by themselves is best. Not as dynamic but flatter, more linear sounding.

WrineX has brought me to my senses.

 

[anji12305]

It was a valiant effort. The Magneplanar mod community has made minor improvements by reinforcement of the frame holding the panels.

Sent from my Nexus 6 using Tapatalk

 

[Disco-Pete]

Hey, no complaints here.

 

[bolserst]

The Celestion 6000 sub woofer for the SL600 was a bipolar, back to back dipole arrangement, or was this an open isobaric dipole arrangement as Winrex describes?

The Celestion 6000 was a compound dipole, both dipole woofers firing acoustically in the same direction.
More details on the concept here (including a Celestion White Paper):
http://www.diyaudio.com/forums/multi-way/46111-legacy-whisper-bass-2.html#post3897099

…WrineX has brought me to my senses.

Yup, Wrinex described the situation correctly.
In case anybody is interested, Wrinex had started a thread where he was investigating stacking of multiple diaphragms in close proximity to each other. There was a spreadsheet posted that could be used to investigate the result of different number of diaphragms and spacings between the diaphragms.
http://www.diyaudio.com/forums/planars-exotics/272742-sandwich-esl-yummie-3.html#post4292045

Using that spreadsheet and estimating the distance between your two panels at around 300mm give the results shown in the attached pics. With the panels acoustically in phase you would get a 6dB bump in LF output, but midrange and higher is compromised with phase issues. Putting them out of phase results in substantial cancellation of output, which agrees with your comment back back in Post#3 “I tried them out of phase and that just sucks the life right out of the sound”

 

[Disco-Pete]

The Celestion 6000 was a compound dipole, both dipole woofers firing acoustically in the same direction.
More details on the concept here (including a Celestion White Paper):
http://www.diyaudio.com/forums/multi-way/46111-legacy-whisper-bass-2.html#post3897099



Yup, Wrinex described the situation correctly.
In case anybody is interested, Wrinex had started a thread where he was investigating stacking of multiple diaphragms in close proximity to each other. There was a spreadsheet posted that could be used to investigate the result of different number of diaphragms and spacings between the diaphragms.
http://www.diyaudio.com/forums/planars-exotics/272742-sandwich-esl-yummie-3.html#post4292045

Using that spreadsheet and estimating the distance between your two panels at around 300mm give the results shown in the attached pics. With the panels acoustically in phase you would get a 6dB bump in LF output, but midrange and higher is compromised with phase issues. Putting them out of phase results in substantial cancellation of output, which agrees with your comment back back in Post#3 “I tried them out of phase and that just sucks the life right out of the sound”

Thanks for that input. I think for my next experiment I may try a full isobaric trial. There's room behind the Monitor 3s to mount directly against them. I'm thinking to use foam gaskets firstly unbroken and then with gaps.

Hey, I have 9 panels!

 

[Disco-Pete]

Make that 12

 

[hhhh]

Was the isobaric electrostat project ever realized? I had the idea to try it myself and came here and this post is the only one I could find. I thought of putting the Acoustat panels almost touching each other with seals that could be applied to the sides with a band that could be tightened.

If it's sealed, it should act like an air piston and have improved bass. I don't think there would be destructive interference because the two panels would be rather closely coupled. An isobaric 1+1 arrangement may be better than a 2+2 by having all the bass and pinpoint imaging with no combing.