Phase Plug design for MW65xx

That surround looks twice as big as the old, is it or is that a photo misnomer?

Nicely done!!

Recent Danny Richie video where he describes the midwoofers @6:25:

"We did an 8 ohm and a 16 ohm version and the 8 ohm version you see here in the NX Studio Monitor, and we went all out with the design on it; polymer chassis, lightweight paper cone, copper shorting rings in the motor structure, all copper coated motor structure, I mean we did everything on this thing, venting through the front, solid aluminum pole piece copper coated *, the works, and the result was one of the best sounding woofers there is on the market to this day."

* I looked the driver up on his website and, yes he did mean solid aluminum phase plug attached to pole piece
https://gr-research.com/product/m-165nq/

https://www.youtube.com/watch?v=7h72KXd8Q3c

A little more descriptive here:

https://data.wescomponents.com/Speakers/Peerless/850467.pdf

VR3 wrote: »

I think we talked about it before but most drivers with a plug are very deep cones. The Polk cones are not very deep in comparison which is why I think you see mixed results.

I do remember someone presenting that "opinion" without any in depth rationalization, in a thread that got nuked by admin due to lack of civility. Doesn't have any bearing on the elimination of the resonant cavity under the dust cap, the greater cooling of the voice coil resulting in less power compression, or the reduction in distortion due to reduction of change in inductance and impedance with displacement of the coil.

I presented information above somewhere that the highs tend to be produced near the center of the cone, ie. near the phase plug. The cone tends to act as a waveguide in this case. The phase plug tends to make the driver behave more as a point source of sound for the highs, which is desireable. But does this look all that much different from the depth of the Polk MWs?

VR3 wrote: »

To refine my view point. A plug shaped like the original dust cap would most likely be better received by the collective

Maybe based upon keeping the looks more traditional, especially if it was black.

But I would hate to lose the benefit I got in my 7Bs where the harmonics are much better dispersed to the point where I can listen just fine way off axis.

VR3 wrote: »

If I recall Ray liked them in the traditional models but not the sda?

Either way, this hobby is all about fun and if you like it that's all that matters!

I just think it's more invasive than most folks want to go

Ray didn't test in anything other than his SDA CRS+, but the driver that he supplied Rob with had a sagging suspension and off centered voice coil. Rob didn't modify the existing driver, it was ones that Ray had in storage somewhere and they weren't listened to prior to Rob's modification.

I miss his posts.