Odp: [sdiy] About that spherical impulse generator...

[Glen]

At 10:01 AM 1/10/04 , Roman wrote:

>Don't know if it was mentioned yet, but what about a big sparkle?
>Say 2 electrodes 1cm apart, huge capacitor for, say 1kV, and
>ignition impulse of several kV to break the air.
>It's small object generating very short pulse, so I reckon it should
>make omnidirectional Dirac audio response
>whadayathink?

That would also be an interesting thing to try. In fact, electrical
discharges are listed in all the literature as one possible source of
stimulus for impulse capture. One should be able to generate a pretty short
duration arc with such an arrangement.

However, I came up with the piezo sphere idea because I thought it would be
a safer alternative to a high voltage electrical arc.

"My, this explosives factory has excellent acoustics! You don't mind if I
set up my 'FlashPoint 2000' impulse capture device, and capture all the
reverberations, do you?"

Okay, that was a little exaggerated. I was more concerned about accidently
electrocuting myself. I might eventually get around to trying the
electrical discharge method, but it gets me into an area where I have
little design experience. I used to repair medical X-Ray equipment several
years ago. We worked with up to 150 kV, and over 300mA capacity. I never
did get shocked while working on any of the gear, but my boss did a few
times (he also fried my DVM once.) The reason I didn't get shocked was my
very respectful attitude toward high voltage. I'd like to keep my
high-voltage safety record spotless, so I thought of making the piezo
sphere.  :)

For those of you more familiar with HV design, I'd appreciate a little
design help. Just how much voltage would be required to flood a large room
with the sound of an electrical arc who's duration is less than a single
PCM sample period? (Let's say the sample rate in this case is 96 kHz, but
it could also be 44.1 kHz in other situations.)

Should I just modify a professional photographic flash system, and
discharge the high voltage directly through the air, instead of through the
xenon tube? (It's too bad I no longer have a large, studio-style, photo
flash to experiment with.)

Should I train "suicide-bomber" insects to fly into a large, bug zapper on
command?

Should I try remotely triggering a stun gun? ...or a piezoelectric
fireplace lighter?

What's the best way to get started, if I take the electrical discharge route?


thanks,
Glen Berry