Linkwitz W-Frame OB woofer

Giri

Member
2018-06-10 3:36 pm
Linkwitz W-Frame OB woofer design question:

  1. Am I correct in understanding that in this design the two woofer voice coils are closer to each other than any other configuration, and the overall distance of the woofer voice coils from that of the mid/tweeter is low because of the low profile? This enables the woofer to be crosses much higher in comparison and also makes for a better point source in a multi-way configuration?
  2. How high can such a design go? Eg: can 3 inch mids also be productively used in this configuration?
  3. If the polarity is reversed, the "FRONT" and "BACK" will swap places and it now operates similar to Nelson Pass's slot loaded woofer. Which of these configurations is preferable?
  4. What are the disadvantages of this design in comparison to other OB designs like the H-frame or U-frame or the I-frame flat baffle?
  5. What are the the general design guidelines/rules of thumbs for such designs? I understand the quarter wavelength rule but I'm also interested in the area of cross-section, volume, depth width etc. of the front and rear slots
 

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1 Coils being close to each other doesn't mean anything in this case!
2 a 3" mid as dipole is too small, a closed box could wrok but with high distortion in low end
3 Net effect is the same or SL and Pass. The purpose is to press air in the slot and in this case other woofer must have reverse phase
4 No disavantages if range stays blow say 500Hz where slot cavity has resonance
5 Maths and simulation are difficult. One question is what happens when this sits on the floor? Better to make a proto and take measurements around it.

Check these similar ones
Prototyping a Dipole Bass System
Gainphile: S19 4-Way Dipole Radiator
 

Giri

Member
2018-06-10 3:36 pm
1 Coils being close to each other doesn't mean anything in this case!
2 a 3" mid as dipole is too small, a closed box could wrok but with high distortion in low end
3 Net effect is the same or SL and Pass. The purpose is to press air in the slot and in this case other woofer must have reverse phase
4 No disavantages if range stays blow say 500Hz where slot cavity has resonance
5 Maths and simulation are difficult. One question is what happens when this sits on the floor? Better to make a proto and take measurements around it.

Check these similar ones
Prototyping a Dipole Bass System
Gainphile: S19 4-Way Dipole Radiator

I will check out the links. Thank you!