Ali Bastanis OB testing & results

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Ali Tait
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Re: Ali Bastanis OB testing & results

Post by Ali Tait » Fri Feb 07, 2020 5:38 pm

One thing I didn’t try was to see if there was any air being shifted out of the gap between the two drivers. Wherever it comes from, there’s plenty of it!
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IslandPink
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Re: Ali Bastanis OB testing & results

Post by IslandPink » Fri Feb 07, 2020 5:53 pm

Is the bass driver EQ done with FIR ( ie. no phase rotation ) or the conventional ( cheaper ! ) way ?
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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Re: Ali Bastanis OB testing & results

Post by chris661 » Fri Feb 07, 2020 6:26 pm

Given the amps, it's not FIR. You'll need my Powersoft T-series amps to do FIR processing.

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Re: Ali Bastanis OB testing & results

Post by Vangelo » Fri Feb 07, 2020 6:32 pm

Ali Tait wrote:
Fri Feb 07, 2020 5:38 pm
One thing I didn’t try was to see if there was any air being shifted out of the gap between the two drivers. Wherever it comes from, there’s plenty of it!
No....its completely dead. One guy on LencoHeaven called it 'a phantom baffle'!

Just to be clear.....the woofers are in phase accoustically, but out of phase electronically.

The concept is not totally original, as Celestion had something similar in the 80's with their SL6000 system.

......and if you think its unusual having the sound generated by the rear of the speaker, have a look at Reflector!

http://www.reflector.audio/

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Ali Tait
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Re: Ali Bastanis OB testing & results

Post by Ali Tait » Fri Feb 07, 2020 6:37 pm

Ah yes, forgotten about the Celestion subs- made for Quad stats were they not?
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Re: Ali Bastanis OB testing & results

Post by simon » Fri Feb 07, 2020 7:43 pm

Vangelo wrote:
Fri Feb 07, 2020 6:32 pm
Just to be clear.....the woofers are in phase accoustically, but out of phase electronically.
Can't quite get my head round this - what would be the practical difference? How is this done? Must be having end of the week brain fade.

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Re: Ali Bastanis OB testing & results

Post by pre65 » Fri Feb 07, 2020 7:51 pm

As the drivers face each other then they need to be electrically out of phase so they both move in the same direction in Isobarik function.

One forward and one backwards but both together.

Does that make sense ? :oops:
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Ali Tait
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Re: Ali Bastanis OB testing & results

Post by Ali Tait » Fri Feb 07, 2020 8:11 pm

Yep exactly that. One amp runs the L/R rear pair of drivers, the other the front pair, connected out of phase in relation to the rear pair.
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Re: Ali Bastanis OB testing & results

Post by simon » Fri Feb 07, 2020 9:57 pm

Riiiiiight, okay. I hadn't appreciated it was isobarik-like. This makes a lot more sense now.

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Ray P
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Re: Ali Bastanis OB testing & results

Post by Ray P » Fri Feb 07, 2020 10:01 pm

In extremis, maybe you could get rid of the frame entirely and mount the drive units on cables from ceiling/floor?

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