Open-Baffle Subs – “Subwoofer Origami”

[otto88]

Did you guys see this?

A good overview of (I think) 11 dipole configuratuions

Subwoofer Origami

many ways to skin the cat

Thanks, John Reekie

 

[gainphile]

How could this be patented ie. 'ripole'. It's like a linkwitz w frame to me !

 

[capslock]

I believe this is not a full engineering patent but more an industrial design patent, similar to what Apple used against Samsung, claiming their phone looked too similar to an iphone.

 

[Elias]

How could this be patented ie. 'ripole'. It's like a linkwitz w frame to me !

Ripole has a side hole where the magnet sticks out, Linkwitz W frame doesn't have it. In patent talk they are completely different

 

[Rudolf]

How could this be patented ie. 'ripole'. It's like a linkwitz w frame to me !

It's not about whether YOU see a difference. It's about the patent officer seeing a difference.

Rudolf

 

[markus76]

How could this be patented ie. 'ripole'. It's like a linkwitz w frame to me !

They are similar but not the same. Axel Ridtahler (which is a very nice guy by the way) and Linkwitz were in contact when the Ripole came out. Send me a PM if you want to get in contact with Axel.

I do use 2 Ripole subs in a near field configuration.

 

[otto88]

IIRC, John the author suggested that a Ripole is:

- the most compact dipole subwoofer,
- with lowest Fs possible

Though the radiation pattern moves away from a dipole

marrkus, do you think yours have those attributes?

 

[markus76]

marrkus, do you think yours have those attributes?

Yes. You can't pack two 12" woofers any smaller.

 

[lolo]

Hi Markus, so the measurements were for a ripole, not dipole?

 

[markus76]

Hi Markus, so the measurements were for a ripole, not dipole?

Which measurements?

 

[lolo]

these?

Comparison of different near field and far field subwoofer configurations

 

[otto88]

Markus

How is the low end, vs other 12 inch * 2 dipoles?

 

[markus76]

these?

Comparison of different near field and far field subwoofer configurations

I've used H-frame dipoles in those measurements.

 

[markus76]

Markus

How is the low end, vs other 12 inch * 2 dipoles?

Well, there IS a low end This is with a 9dB boost at 24Hz and a 24dB high pass at 20Hz:

This is unsmoothed data and 1Hz frequency resolution

 

[otto88]

Nice - what are the woofers

 

[markus76]

Nice - what are the woofers

In which configuration, dipole or Ripole? The dipole is described at
http://www.diyaudio.com/forums/subwoofers/227322-visaton-ws25e-8-h-frame.html#post3322763

I promised Axel Ridtahler (inventor of the patented Ripole) not to disclose details about my construction. You would need to contact him directly at axel.ridtahler [at] kit.edu

 

[sumacSK]

Well, there IS a low end This is with a 9dB boost at 24Hz and a 24dB high pass at 20Hz:

This is unsmoothed data and 1Hz frequency resolution

Wow that is funtastic result for such a simple and inexpensive subwoofer config. Where do you cross those subs? Did you ever noticed "sounds coming from the back"? How much SPL at listening position can you produce with those two subs (visaton drivers in H frames)?
thanks

 

[markus76]

The frequency plot shows the Ripole. Didn't measure max. SPL for the H-frames.

 

[skorpion]

This FR is impressive, but remember SPL and low frequency response will be generated by cone area, cone movement and cone resonance. Now nothing is disclosed about the speaker units, so SPL dB is not known and 12" as judged what markus said himself is probably a SLS12 from Peerless. By itself it won't play excessivly high in a Ripole. But be a superb SUB. As Ripoles in fact are exellent OB SUBs with the right speakers.

/Erling

 

[john k...]

Well, there IS a low end This is with a 9dB boost at 24Hz and a 24dB high pass at 20Hz:

This is unsmoothed data and 1Hz frequency resolution

Curious, what was the measurement distance?