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This project is a modification of a hybrid ESL speaker shown on my DIY ESL website here:
I'm replacing the original perf-metal ESL panel with a segmented wire-stator ESL panel with selectable wide and narrow dispersion modes. My old perf-metal flat panels give incredible slam and imaging at their focal point but their miniscule "head-in-a-vise" sweet spot isn't much good for entertaining guests. So this project is a way to have it both ways:
Each stator uses a vertical array of (132) copper coated .035 diameter TIG welding rods glued onto a black plastic egg crate support (florescent light diffuser).
The conductors are physically segmented into (11) discrete groups of (12) rods, and electrically segmented into (6) discrete groups (center group + 5 outer group pairs).
In narrow dispersion mode, all wire groups are directly coupled to the amps/transformers; driving the diaphragm uniformly across its entire surface and the panel radiates a planar wave front giving a tightly focused sweet spot for best imaging and slam.
In wide mode, dispersion is achieved the same way Peter Walker did it in the Quad ESL 63; using electrically segmented conductors receiving sequentially delayed signals via a resistor/capacitor delay network. But where the Quad 63 used concentric rings of conductors in a delay line, driving the diaphragm from the center outward, as a point source radiating a spherical wave front, my panels use vertical wire groups driving the diaphragm from the centerline outward, as a line source radiating a cylindrical wave front.
I plan to use a pair of Soviet military rotary switches to select between narrow and wide dispersion (switch would jump across the resistors). However, the switches have not yet arrived from Belarus so for the time being the panels are wired for wide dispersion mode only.
I have just completed the panels and installed them but I will have to wait until next week to start tuning, as I spend the weekends with my GF. However, I did play the panels for a few minutes this morning just to make sure there were no arcing problems.
At first play I can tell that, unlike my old non-segmented flat panels, these new panels have NO pronounced sweet spot. Right now they sound bass heavy, as the EQ'ing is still setup for my old non-segmented panels which are very bright.
I will update again next week after some tuning and tweaking.
For now, here are the build pics:
Mating front and rear stators with diaphragm and copper foil charge ring installed:
Completed panels:
I'm replacing the original perf-metal ESL panel with a segmented wire-stator ESL panel with selectable wide and narrow dispersion modes. My old perf-metal flat panels give incredible slam and imaging at their focal point but their miniscule "head-in-a-vise" sweet spot isn't much good for entertaining guests. So this project is a way to have it both ways:
Each stator uses a vertical array of (132) copper coated .035 diameter TIG welding rods glued onto a black plastic egg crate support (florescent light diffuser).
The conductors are physically segmented into (11) discrete groups of (12) rods, and electrically segmented into (6) discrete groups (center group + 5 outer group pairs).
In narrow dispersion mode, all wire groups are directly coupled to the amps/transformers; driving the diaphragm uniformly across its entire surface and the panel radiates a planar wave front giving a tightly focused sweet spot for best imaging and slam.
In wide mode, dispersion is achieved the same way Peter Walker did it in the Quad ESL 63; using electrically segmented conductors receiving sequentially delayed signals via a resistor/capacitor delay network. But where the Quad 63 used concentric rings of conductors in a delay line, driving the diaphragm from the center outward, as a point source radiating a spherical wave front, my panels use vertical wire groups driving the diaphragm from the centerline outward, as a line source radiating a cylindrical wave front.
I plan to use a pair of Soviet military rotary switches to select between narrow and wide dispersion (switch would jump across the resistors). However, the switches have not yet arrived from Belarus so for the time being the panels are wired for wide dispersion mode only.
I have just completed the panels and installed them but I will have to wait until next week to start tuning, as I spend the weekends with my GF. However, I did play the panels for a few minutes this morning just to make sure there were no arcing problems.
At first play I can tell that, unlike my old non-segmented flat panels, these new panels have NO pronounced sweet spot. Right now they sound bass heavy, as the EQ'ing is still setup for my old non-segmented panels which are very bright.
I will update again next week after some tuning and tweaking.
For now, here are the build pics:
Mating front and rear stators with diaphragm and copper foil charge ring installed:
Completed panels:
Attached Files
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