TAD woofer questions -- overhung vs. underhung

[louped garouv]

do all of the TAD 160** (1601a, 1601b, 1602, 1603, etc.) woofers employ the same philosophy with respect to being under- or over- hung?



VOICE COIL The TL-1601a employs an edgewise-wound long-travel type voice coil. Since the coil stays completely within the magnetic gap even during peak excursions, bass output is powerful, and distortion low, at all input levels. And since the coil makes more effective use of the flux within the magnetic gap, it provides high conversion efficiency. The voice coil bobbin and adhesive materials have high heat resistance.



VOICE COIL The voice coil is relatively short so that it remains within the magnetic gap even during peak excursions. But its long travel distance results in reduced distortion at high input levels. The coil we use is ribbon wire, wound edgewise on a bobbin with heat-resistant adhesive. Making more effective use of the flux, it assures increased acoustic conversion efficiency and safe operation even when faced with 300 watts max. input.



VOICE COIL A high maximum input of 500 watts is achieved through the use of an edgewise-wound, long-travel voice coil. Making more use of the flux within the magnetic gap, this voice coil provides higher transducing efficiency. Moreover, high linearity is maintained over a long distance for lower distortion. Both the voice-coil bobbin and the adhesive are made of a highly heat-resistant material to permit high maximum input.

[Guido]

Here we go.
As TAD does not tell us about the pole plate thickness and winding length (Except with the 1801) we need to do some calcs ourself.

1801
With the VC diameter, Maxwell and Tesla figures we can calculate that the pole plate is 8mm.
Winding length is 23mm according spec.
So Xmax = (23mm - 8mm) / 2 = 7.5mm
Bingo, Xmax is 7.5mm according to spec.
Clearly an overhung design

1602
With the VC diameter, Maxwell and Tesla figures we can calculate that the pole plate is 7mm.
Xmax spec is 5.5mm according spec.
Winding length = 2x5.5+7 = 18mm
Very similar to an 2235 and clearly overhung.

1601a
With the VC diameter, Maxwell and Tesla figures we can calculate that the pole plate is 7mm.
Xmax spec is 8mm according spec.
Winding length = 2x8+7 = 23mm
Clearly overhung.

1601b
With the VC diameter, Maxwell and Tesla figures we can calculate that the pole plate is 7mm.
Xmax spec is 8mm according spec.
Winding length = 2x8+7 = 23mm
Clearly overhung.

I would love to see an 1602 with 23mm winding length !!

[louped garouv]

thanks!

speaking of Tesla....

that man did some wild and wonderful things not too far from me....
they say he could make lightning.... well almost....

i need to read up on Mr. Tesla....


http://www.pbs.org/tesla/ll/index.html

Arriving at Colorado Springs in May 1899, Tesla went to inspect the acreage. It was some miles out in the prairie. He told reporters that he intended to send a radio signal from Pikes Peak to Paris, but furnished no details.

In the midst of Colorado's own incredible electrical displays, Tesla would sit taking measurements. He soon found the earth to be "literally alive with electrical vibrations." Tesla came to think that when lightning struck the ground it set up powerful waves that moved from one side of the earth to the other. If the earth was indeed a great conductor, Tesla hypothesized that he could transmit unlimited amounts of power to any place on earth with virtually no loss. But to test this theory, he would have to become the first man to create electrical effects on the scale of lightning.

The laboratory that rose from the prairie floor was both wired and weird, a contraption with a roof that rolled back to prevent it from catching fire, and a wooden tower that soared up eighty feet. Above it was a 142-foot metal mast supporting a large copper ball. Inside the strange wooden structure, technicians began to assemble an enormous Tesla coil, specially designed to send powerful electrical impulses into the earth.

On the evening of the experiment, each piece of equipment was first carefully checked. Then Tesla alerted his mechanic, Czito, to open the switch for only one second. The secondary coil began to sparkle and crack and an eerie blue corona formed in the air around it. Satisfied with the result, Tesla ordered Czito to close the switch until told to cease. Huge arcs of blue electricity snaked up and down the center coil. Bolts of man-made lightning more than a hundred feet in length shot out from the mast atop the station. Tesla's experiment burned out the dynamo at the El Paso Electric Company and the entire city lost power. The power station manager was livid, and insisted that Tesla pay for and repair the damage.

For nine months Tesla conducted experiments at Colorado Springs. Though he kept a day-to-day diary that was rich in detail, the results of his experiments are not clear. One question has never been definitively answered: Did Tesla actually transmit wireless power at Pikes Peak?


There are some reports that he did transmit a signal several miles powerful enough to illuminate vacuum tubes planted in the ground. But this can be attributed to conductive properties in the ground at Colorado Springs.

apparently he made up quite the circuit too
:)

http://www.teslasociety.com/teslarec.pdf