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Multi-Way Conventional loudspeakers with crossovers

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Old 29th July 2011, 03:01 AM   #101
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Quote:
Originally Posted by Salas View Post
You lower Fs by sqrtHz
Perhaps a bit misleading without the conditions.

A tightly coupled isobarik woofer has 1/2 Vas, same Fs, same Qt, 2x mass and BL vrs a single one of the woofers.

So (ignoring the volume of the isobarik chamber) if you put a compund driver in a box volume V, it has the same response as a single driver in a box of 2*V volume. So isobarik simply lets you use a box half as big (+ chamber) as you would need for a single woofer.

4 drivers (2 isobarik pairs) can be put in the volume you would use for 1.

Putting
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Old 29th July 2011, 03:25 AM   #102
Salas is offline Salas  Greece
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You are right. I had in memory something about targeting the same volume and using it for going lower scenario or I dug it up from simple mass loading. Ignore my earlier post. Bad memory. Compound just allows half a box is a straight rule.
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Old 29th July 2011, 02:03 PM   #103
chops is offline chops  United States
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Originally Posted by Salas View Post
The loss is you go 4 Ohm without any 2.83VSPL referenced increase.
But you also reduce the work load on the drivers by half, as well as lessen harmonic distortion, especially if one of the drivers is physically inverted from the other.
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Old 29th July 2011, 02:08 PM   #104
Salas is offline Salas  Greece
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Of course. Those are quality gains to consider as positives. Still there is a 3dbW loss in sensitivity that demands horsepower. The good thing is there are affordable high SPL pro woofers around that were not the norm in the 80s when some companies like Linn used the principle, plus class D. So this Isobarik thing becomes very viable again IMHO.
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Old 29th July 2011, 02:14 PM   #105
chops is offline chops  United States
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Originally Posted by Salas View Post
Of course. Those are quality gains to consider as positives. Still there is a 3dbW loss in sensitivity that demands horsepower. The good thing is there are affordable high SPL pro woofers around that were not the norm in the 80s when some companies like Linn used the principle, plus class D. So this Isobarik thing becomes very viable again IMHO.
Exactly, hence why I'm seriously considering incorporating an isobaric design in my next project.
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Old 29th July 2011, 02:25 PM   #106
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Will save much space, braces the cabinet, push pull back magnet linked anti resonance trick, not a bad dish. Its they had 87dB B139s in the 80s and they got 'em down to 4 Ohm on top of it, plus the amps were not up to the task.
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Old 29th July 2011, 07:33 PM   #107
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But you also reduce the work load on the drivers by half, as well as lessen harmonic distortion, especially if one of the drivers is physically inverted from the other.
Has anybody done distortion testing for an isobaric pair of woofers vs a single woofer (in double the size)?

I'm curious to see how the distortion actually changes.
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Old 29th July 2011, 07:42 PM   #108
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Not mwasurements, but worth reading.
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Old 27th November 2012, 12:12 AM   #109
JeffL is offline JeffL  Australia
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Anyone who has 2 identical woofer/midrange drivers , note Kef Blades .
Have tried same config with 2 Peerless 832873 . Sounded lower distortion .
Need another Peerless 830869 , so can do single Vs dual distortion tests .
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< KEF_Blade_3DCab Full Screen Image &mdash; Reviews and News from Audioholics >
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Old 27th November 2012, 04:18 AM   #110
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Originally Posted by Ceibal View Post
What I am looking for is a woofer/tweeter combo that will give me extreme detail while being natural and smooth. I thought maybe the Seas Excel would do that for the woofer, not sure about the tweeter. I am still considering the morel supreme 130. Is there a better tweeter I should consider? Also, what size woofer would be best? I was looking at the 7 inch.

What is the difference between paper and magnesium? Will one provide more bass response/ better detail?

For tweeters why not look at Hiquphon?
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