Jazzman MkIII Hybrid ESL

[Jazzman53]

Hi all,

I've pretty much retired from speaker building but I want to share my last and final ESL project. I don't know how I would top this one anyway-- It's the finest speaker I've ever built.

I still maintain my how-to ESL website, and I get a lot of satisfaction from helping others build their dream speakers. The labor is horrendous (no sane person would attempt it) but the results are amazing and the journey can be life changing.

Description:
The MkIII is a flat panel, wire-stator, hybrid ESL with electronically tailored dispersion and dipolar bass from an Eminence KappaLite 3012LF woofer on a modified-H open baffle (OB).

The speakers + subs are 6-channel stereo with a DSP crossover.

An KappaLite woofer isn't typically used on an OB due to it's low-Qts (0.32)/stiff suspension-- but it doesn't need to go low with the subs in play, and it blends superbly with the ultra-fast electrostat, which is the priority. It's spectacular mid-bass punch is just icing on the cake.

The stators are 90-wire arrays, symmetrically segmented in 15 discrete six-wire groups to function as a line source projecting a cylindrical wavefront. This arrangement gives wider and smoother-trending dispersion than a curved panel ESL, or even most conventional speakers.

The details of how the stators' electrical segmentation tailors the dispersion are given on my website below, along with several build videos.

Enjoy!
Charlie

Jazzman's DIY ESL Page (permission previously granted to post my website here)
Jazzman MkIII Intro Video
Stator build video
Panel assembly video
MkIII Prototype playing

Below: The Jazzman MkIII ESL and matching Ripol subwoofer



Below: Back view showing the amp-interface assembly and Eminence 3012LF woofer.


Below: Sketch showing the wire lacing and segmentation layouts.


Below: Stator in its assembly jig with the oak support lattice glued down over the wires.


Below: Completed 90-wire stator.


Below: Frame assembly glue-up


Below: Front stator being bonded onto the diaphragm, on the bike tube tensioning jig.


Below: The amp-interface assembly (HV bias supply & tandem step-up transformers).


Below: Jazzman MkIII speaker with its magnetic grill covers on.