On Sun, 07 Oct 2007 10:59:48 -0700, GoldIntermetallicEmbrittlement
g wrote:
On Sun, 07 Oct 2007 11:06:50 -0500, John Fields
wrote:
On Sat, 06 Oct 2007 23:44:23 +0100, Eeyore
wrote:
John Fields wrote:
Eeyore wrote:
marco9 wrote:
Hey guys new to the NG, but have been monitoring for a bit. I am in need of
a schematic for a two way floor monitor speaker cabinet....heres the
details.....maybe someone can help!!!
the box contains :
1 - 15 Inch 250W H325 woofer which is 8 Ohm
(Not sure of Brand)
1 - Peizo Tweeter (Horn) Fostex 025H30 also 8 Ohm
Piezo tweeter don't have Ohms
---
They don't?
Then how do they manage to do work?
They have Farads.
---
Farads doesn't make them work, what does is the poling of the
ceramic material, which then makes it piezoelectric.
He try to learn something:
http://www.americanpiezo.com/piezo_t...avior.html#top
http://www.pulsardevelopments.com/pr...l/piezoan.html
---
And I'm sure you're going to nitpick now on account of the real
component of work.
---
No need to, now that you've admitted that there _is_ a real,
resistive component to work. Not only that, a piezo transducer
exhibits an electrical (as well as mechanical) _impedance_ (as
opposed to merely a reactance) so there's also a real, resistive
component there.
---
I suspect that may be outside the OP's area of scientific
understanding though.
---
So what? Do you think that somehow minimizes your ignorance?
We used a 200 plus wafer stack for micro-machining, so the pre-load
pressure, as well as the work pressure feedback also causes a reactance.
They operated at 800V from 20 to 20,000, and the nano-machining centers
are used for race horse contact lenses, and the machines were bought/made
for Bausch and Lomb.
One could cut an optical grade surface on the face of a spinning lathe
spindle, or even turn a round shaft into a square shaft with one of these
FSTs (Fast Tool Servo) tool heads attached. Total traverse, less than 2
mm. Surface finish/quality accuracy, less than 2 microns.
---
Interesting.
Years ago, for the U.S. Navy, I designed and built a 40kHz projector
using a hollow spherical segment of PZT8 as the projector and a
couple of ENI 1kW power amps to drive it, underwater.
When we fired it up a visible, golf-ball sized area of cavitation
appeared at what was the focal point, the center of the sphere.
Pretty neat machine. :-)
I'll post pictures if anyone's interested.
--
JF