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Yes Rob -Thanks for the heads up on this stuff - Also picked up some Alpair 7’s for trying in the TL cab that I have then some 15" Hawthorne Augies plus silver Iris coax w/o the tweeters.
The Super Sevens though - a really rare opportunity in the UK
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Fantastic Andy.
Please keep on doing all this mad shit so we don’t have to 
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Progress, little may it be, so far…
Favouring the H2606 tweeter config so far, maybe leaning towards a simple closed box for the 285GMF that can be a fair bit smaller and sit close to the wall, and use the sub.
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are the woofers isobaric?
Nope - servo open baffle have yet to understand the wiring.
What does the servo do?
Google AI to the rescue
How Servo Open Baffle Works
Unlike traditional passive speakers, a servo system uses a feedback loop to ensure the speaker cone follows the electrical signal exactly.
- Sensing Coil: The woofer typically features a second, lightweight “sensing coil”. As the cone moves, this coil generates a signal that represents the actual physical motion of the driver.
- Error Correction: A dedicated servo amplifier compares this feedback to the original music signal. If the cone lags or overshoots due to inertia or room air resistance, the amplifier instantly applies a corrective signal to bring it back in line.
- Active Damping: The system can electrically “brake” the cone, stopping its movement almost instantly when the signal ends. This results in extremely fast settling times and highly detailed, “un-smeared” bass
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Wot e said
Well, the Bottlehead Kaiju is finished, whoop, whoop!
All voltages hit as required and a bit of foo added.
Played for about six hours on sacrificial speakers that lived to fight another day!
Now to plug it into the main system
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Very nice
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I wanted to try a simple 2-way with the 285GMF and tweeter, still in OB for now and a quick lash-up with the BMS 4524 and it sounds pretty darn good, better integration than the 3-way versions. Certainly a bit of fiddling around to be done (as there no L-Pad on this lash-up) and I’m just using the caps/inductors that I already have.
VituxCAD gives me the simulations below which seem to work well. I had discounted the 475PB as I could not get a good sim out of it in the 3-way or 2-way with 2nd order slopes but actually gives a nice response so I’ll give that a quick go first, as I plan to move those on to an interested party.
Also took the chance to use these direct with the Decware Zen (no MiniDSP) and I like what I’m hearing, only 2wpc but with these ~100dB 285GMF drivers there seems to be more than enough output for me.
The 4524 flattens out very nicely with just a single cap, as I experimented with before. The eventual acoustic crossover is around 1.5kHz on all of these. These waveguide tweeters all have a rising response to the low end due to the loading so seem to flatten out quite well with the higher crossover point and the 6dB/Octave single cap.
- 475PB 1st order ~5kHz (-4dB L-Pad)
- H2606 1st Order ~8kHz (-1.5 L-Pad)
- 4524 1st Order ~20kHz (0.5dB L-Pad)
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Chris - That’s great work -
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Today swapped out the 450mm dia phenolic resin horns on my recently acquired speakers for my own 3d printed effort - In the end it wasn’t too much of a chore.
These black horns are modelled to Iwata 330 design.
In other work I have 3d printed an adaptor and fitted a mark audio driver into my black TL cabinets
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That horn looks great Andy!
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Has the Mrs suggested it would look better in a glossy white yet 
She need not worry, the next effort is in cold white and very large 790 x 520
264 hours printing for each horn - Only two 2day prints away from a first horn.
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