Author Topic: Isobaric speaker  (Read 201 times)

funkyjazzjunky

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Isobaric speaker
« on: September 01, 2017, 09:37:17 AM »
Any of you ever play using an isobaric speaker?

VMG

David Houck

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Re: Isobaric speaker
« Reply #1 on: September 01, 2017, 01:12:20 PM »

pauldo

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Re: Isobaric speaker
« Reply #2 on: September 01, 2017, 04:34:09 PM »
How very interesting.
1984 Distillate Zebrawood

peoplechipper

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Re: Isobaric speaker
« Reply #3 on: September 02, 2017, 12:29:56 AM »
huh, learned something new today...

sonicus

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Re: Isobaric speaker
« Reply #4 on: September 02, 2017, 08:04:15 AM »
I sincerely would like to audition one of these :)

funkyjazzjunky

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Re: Isobaric speaker
« Reply #5 on: September 02, 2017, 09:46:16 AM »
Used to have an isobaric sub-woofer in a car.  I think a bass cabinet would sound awesome if designed properly.

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lbpesq

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Re: Isobaric speaker
« Reply #6 on: September 02, 2017, 12:24:56 PM »

"OBC212 positions two front-facing speakers, one behind the other. The space between the front speaker’s magnet and the rear speaker’s cone is airtight, ensuring that both speakers vibrate in conjunction with one another, thus keeping them in phase."

I never heard of these before.  From the description, it sounds as if the rear speaker is acting like a turbo charger with both the front magnet and the rear speaker working the front cone.

Bill, tgo
« Last Edit: September 02, 2017, 12:27:13 PM by lbpesq »

xlrogue6

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Re: Isobaric speaker
« Reply #7 on: September 02, 2017, 12:35:41 PM »
Ampeg built them in the early 90's. The SVR212 in the link is the only one I've seen, heavy and unwieldy, decent but unremarkable sound. The 215 version would require a crew to move, I'm guessing. http://www.guitarcenter.com/Used/Ampeg/SVR212-Bass-Cabinet.gc


ETA: Unlike the Orange, the Ampeg used one front facing and one rear facing driver, as the GC pics show. IIRC, the drivers were out of phase so the reflected back wave from the rear driver wouldn't cancel the front driver. Obviously this arrangement would make cabinet placement in relation to the back wall (and gods forbid you find yourself in a situation without one!) somewhat critical.
« Last Edit: September 02, 2017, 02:36:04 PM by xlrogue6 »

keith_h

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Re: Isobaric speaker
« Reply #8 on: September 02, 2017, 12:41:22 PM »
The Orange cabinets are ported from what I can tell so the sound from the back speaker would be coming out the port.  As near as I can tell the advantage of the isobaric design is the ability to use a smaller cabinet. There are some drawbacks with distortion but how noticeable it is I don't know. Another is although the physical cabinet dimensions are smaller they can weigh more than a larger cabinet with similar functional characteristics. Looking at some of the designs the most efficient and having the least distortion appears to be two speakers sealed face to face with one speaker sticking out of the cabinet. Not a very good design for live music.

I was unable to find any detailed spec's on the Orange cabinet and would be interested in knowing what the SPL rating and measurements are in addition to the frequency response curves. This would give me an idea of how they compared to other more traditional designs.