Cellulose, carbon and alu domes, different size and 44.5mm coil. Time to make same moving coil diaphragms ;-)
Optimum dome height ~8mm@44.5mm diameter for OS means HF roll-off frequency, also mismatch between phase plug curvature and diaphragms forms different roll-off e.g. differences between 18sound diaphragms and STX.
Optimum dome height ~8mm@44.5mm diameter for OS means HF roll-off frequency, also mismatch between phase plug curvature and diaphragms forms different roll-off e.g. differences between 18sound diaphragms and STX.
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Thanks to all the DIY guys behind the actual design itself.......
Thanks to forum member jzagaja and Autotech for helping with the prototypes and getting the fiberglass models produced. And then I decided 'to go for broke' to get one made that anyone can afford.
The mass production SEOS™-12 is finally ready for pre-orders!
Plastic SEOS-12 Pre-Order DIY Sound Group
Thanks to forum member jzagaja and Autotech for helping with the prototypes and getting the fiberglass models produced. And then I decided 'to go for broke' to get one made that anyone can afford.
The mass production SEOS™-12 is finally ready for pre-orders!
Plastic SEOS-12 Pre-Order DIY Sound Group
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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Nice set up you have there. Can you give some specifics on the drivers in the VOT boxes and the crossover? Are you using the original Iwatas that does not have metal reinforment in the driver flange area? I am wondering about long term stability of the horn hanging off the drivers like you have. Do you think they will hold up over time and not develope fractures in the stressed areas?I've been using the JBL 2446h CDs with aftermarket aluminum diaphragms (Radian I believe) with very good results. However I do look forward to trying the Truextent diaphragms in the near future.
Thanks,
David
PS I'm still wondering about Altec drivers used in Iwatas. Anybody have any experiences with this combo?
Hello David,
Those are the original IWATAs that did not have the metal reinforcement ring. They were weak. In fact one of mine broke. The waveguide pulled completely free of the MDF mounting ring. When I made the repair I added fiberglass to build up the transition from MDF flange to waveguide. The fix worked and I don't think there is much of a chance that they will come apart again.
The driver in the VOTT box is a GPA 416C. GPA makes a very nice product. Their 416C driver in a stock Altec 828 cabinet is usable (with boost) to 40Hz. The crossover is active and is set at 650Hz / 18dB per octave. I use Dirac Live running in a Datasat RS20i Processor to smooth the response. Bass Management extends the bottom end to 20Hz. I'm very happy with the results.
What xover was used for this measurement? Or is it only the MR section of the 4590?
Cheers for that info. Not the way I'd use the 4590 myself: I much preferred a a steep active xover at 6k5. Notwithstanding my preferences, most people would have something more there than what you have, so not too much should be made of the comparison between it and the radian, based on that.
