speaker degeneration

[nyazzip]

i should clarify- this post is in reference to guitar speakers and amps....
...so i have a 2x12 box i have been unhappy with...it is loaded with two 16 ohm speakers scavenged from a closed 4x4 laney speaker box circa 1985.
at one point in the mid '90s, this 4x4 cabinet was immersed during a chicago basement flood- the lowest 2 speakers got soaked, but not quite up to the motor assembly.
a few years ago i bought some black goo from PartsExpress and i proceeded to paint the entire speaker cones with it; it is a glossy black rubbery liquid. in retrospect i suppose it was intended for surrounds only.
anyway, these speakers have since always seemed like they sounded lifeless, yet harsh. to be fair, after the 4x12 and the rubberizing, i have only ever had them mounted in this newer homemade closed 2x12 box. they may actually sound ok in other applications. but i digress.
i have always kind of wanted to physically mess with speakers just to see what happens. i figured these flooded, rubberized '80s metal speakers are a good candidate, so....this evening i began my experiment by poking holes in the speaker cones, near the dustcap, with a straight pin. lots of holes. i set up a mic, and recorded the first wave of damage: hundreds of pinholes in each cone, radiating a half inch from the dustcap. (i neglected to record an "untouched" reference; at that point it wasn't going to be scientific...then i got into it).
next, i poked hundreds of more holes, again radiating out from the dustcaps. by the end of this barrage, about half of the speaker cone area radius was completely perforated. record. next, i continued to perforate the cones, out to the last of the "ribbing"...say about 4/5ths of the speaker cone area, now poked with thousands of holes.
on the last(but not yet final) experiment, i inserted dozens of straight pins into each speaker cone, and left them there....so they looked like the "pinhead" guy from that '80s horror flick. (http://s265.photobucket.com/albums/ii229/nyazzip/ )

so, what i discovered: mostly, i was shocked at the lack of impact that the pinhole perforations had on the speakers...i mean, i riddled these things with thousands of holes, (probably on average about 2mm spaced), and the actual sound of the speakers was negligable! wow! my general observations were:
1)the efficiency, or apparent volume, of the speakers appeared to decline a bit with the introduction of more holes.
2)the eq profile definitely changed as i perforated the speakers....honestly, i liked the sound better with the most pin holes: the sound was less resonant around the lower midrange frequencies, much like i would imagine acoustic stuffing or damping would do. the holes made it sound less "boxy" or "honkey".
...i wonder if poking all those holes in essence simulated an open backed cabinet?

3)lastly, the test with the dozens of voodoo pins sticking out, actually sounded GOOD! i expected most of the pins to go flying, and to rattle about horribly, but they didn't move! also, the pins seemed to lend a curious prescence bite, or metallic pick attack....but it was subtle. in fact the recording didn't really illustrate it well at all, but i could definitely hear it from where i was sitting.

tomorrow i think i will continue the speaker degeneration, and maybe break out the scissors, and start cutting them to ribbons....but in short, i guess what i learned is, if you have a small hole in a speaker cone, or even hundreds of pinholes, its really not a big deal, even at fairly robust listening volumes!

[Vince]

I hope you have applied for a patent!!! Cone Pins...what a concept.
And it will sell!! Vince