EnABLed speaker baffle

[Davet]

It is of no consequence as to what Bud's son actually thought. Bud's son was the catalyst that inspired Bud to develop enABL. The difference between Tuxedocivic and Bud is that one chose to dismiss his son's impression, and the other opted to try to understand why the child thought what he did.

Bud may not have scientifically proved what the child heard, but has been able to repeat the phenomena to such a degree that any number of adults sense that there are no speakers.

Very much like an apple falling was the inspiration for Newton.

[nicoch58]

we must think out of the box !with one eye on the past (1930)

use full range is a good start try in Openbaffle

[TheGimp]

Originally Posted by doubtingthomas

No, you are right, I'm on my third glass of wine but it still only gets us up to 2m/s.

You need to calculate slew rate to get the peak velocity, which is 2 * Pi * f * Vpk = 6283mm/s or 6.3 meters per second or roughly 22kph.

obviously the air is not flowing moving at 22kph, but there are rairifications and compressions instead of mass air movement.

Splash in a pond, and there are ripples, but the water does not flow with them.

[doubtingthomas]

I know, mine was an average but thanks for nailing it down precisely.

[doubtingthomas]

Originally Posted by BudP

Imagine it is 1972, in LA and you walk into Henry Radio at Walt Jr's phoned insistence and he shows you a pair of Ohm F Demo's he has conned Marty into sending him. He lifts the cover off of one unit and your eyes fasten on the odd looking slits in the paper, at the bottom of the long inverted cone and you think to your self "well, that's wrong". You foolishly mention this to Walt and he says "can you do any better?"

And so you purchase a pair for $600 and proceed to apply these pattern blocks that arose in your minds eye, immediately after you had the thought about how wrong what they had done was (this being a normal event for a graduate of the Art Institute of Chicago). A month later you have a pair of Ohm F's that emit a spherical wave front, rather than a frequency stepped, cylindrical one and you could tell this only because the sound does not change no matter your position around the speaker. You fiddle about with other direct radiator drivers and find some fairly dramatic improvements in quality (remember, this is still the 70's and most speakers were not very well designed in comparison to what is available today). You look for test equipment that might show you something and find nothing you can possibly access or afford.

5 years later your 7 year old son rips the input plug from the heavily uprated SAE, Germanium transistor Mark 3A amplifier. The wire wound resistor network protecting the transistors evaporates, as do the transistors and the filter capacitor emits heavy smoke. The Ohm F crumples and you and your son are deaf for a few hours, while he cries in a wild and crazed fashion. Eventually mom calms him and asks what that was all about. Son says" I wanted to let the music people out!!!!" and begins crying again. Eventually you learn he thinks he has killed them all by imploding them in an "inplosion".

Upon reflection over this period of time, you realize that your own childhood had a number of instructive pursuits that likely as not provided fodder for this madness. And, you go on a hunt for the obvious explanation for why the spots of paint have made a big enough difference that someone so young and innocent of malice could have become convinced there were live people inside of the speaker cone. Surely there must be an explanation available....

The only mention of anything that even remotely seems to bear upon this effect, upon a non pistonic driver (do read Lincoln Walsh's papers), might be a single chapter from Baranek's "Acoustics", where he admits that the piston models that the rest of the book is devoted to, don't really explain what he shows in graphic format within that chapter. And so you begin to think about the problem....

There, you have it.

Cute, schmaltz v/s science.

[doubtingthomas]

A further thought is, that most people being the way they are a sugar coated lie will allways win over an unpalitable truth, that's why we are surrounded by fruitloopery.