GR Research Dipole Subwoofer

[Tubenstein]

Anyone has built the GR Research Subwoofer??

What is the ideal crossover point for this subwoofer with W frame??

SW-12-16FR

http://www.gr-research.com/pdf/obsub.pdf

Thanks!

 

[esl 63]

To little Area. only 10". Half the area of 15" woofer.
I use 3x15" per channel (6x15") woofers with approx same x-max 14,5 mm.
I would say you need 8 of them at least.

 

[esl 63]

One more thing... let the elements play in the SAME direction.
This will give you more 2nd harmonic distortion. But it will mask the higher harmonics (3d, 4th, 5th etc)
Sounds better this way.
Yes slightly higher THD, but remember your own ear is producing significant amount of 2nd harmonics. Up to 10% in the low frequency region. And the added 2nd harmoic is the least disturbing harmonic. Actually you prefer it after listening test...

 

[scottjoplin]

You don't need 8 using W frames.

Tubenstein, a subwoofer is usually crossed around 80Hz or so, in order that placement can't be heard

 

[Juhazi]

More about this dipole V or W dual (sub)woofer type

LX521 Description
Electro-acoustic models
W Frame Dipole question
Prototyping a Dipole Bass System

 

[Tubenstein]

You don't need 8 using W frames.

Tubenstein, a subwoofer is usually crossed around 80Hz or so, in order that placement can't be heard

The funny part is the Gradient dipole bass has 2 different versions, one crossover at 110Hz for the Quad ESL and the other at 200hz for most conventional loudspeakers.

GRADIENT NERO - Gradient Labs Oy

 

[scottjoplin]

Then they would need to be placed close to the mains or use delay to time align although it would still be possible to hear their location. The main advantage of subs is to able to place them anywhere to fight room modes.

 

[bentoronto]

You don't need 8 using W frames.

Tubenstein, a subwoofer is usually crossed around 80Hz or so, in order that placement can't be heard

Time now for you to reconsider repeating that old "fact" - that is based on lab tests.

On music with clean speakers and sharp XO, 130 Hz is just fine. That's a substantial benefit because then your mids don't have to struggle to get down to 80 Hz which requires much bigger drivers and cabs or OB panels.

That "80" figure is repeatedly disputed by folks who have tried higher. Try it yourself.

B.