the pair of vintage Allison top of line AL130 i bought recently ! , the boxes good for shipping. ( u haul )
PIA sellers who will not ship ! "local pick up only " have had to hire a guy on CL nearby seller to go pay him ,get them. box them up ! i e mail him a prepaid shipping label!
to find working survivors you have to look all over USA !
Jack Dale
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Top contributor
this why the Allisons were / are magic !
SCORE !
found some bucket list Alllison Al130 speakers ! they were top of the Alllison line !
Back in the day , these speakers were a phenom smoking most other speakers in reviews !
even Consumers Reports scientists and engineers said it was the best speaker they had ever heard and made it a "best buy " ! LOL 
need some OEM midrange as someone put in some lame AR midrange when the original mid-drivers failed in the 1980s'! ( and the tweeters got damaged in shipping 
) sourced these fr the 2nd owner , orig owner recently replaced the woofers w/ orig NOS woofers!
sadly NO current speaker maker has the knowledge ,expertise, skills or ability to make the patented Allison Convex tweeters and midranges !
( they were notoriously difficult to make! )
sad that, as they were one of the MOST innovative and effective innovations EVER in speaker design.
even now, 50 years on nothing is superior or equal .
Roy allison said :
And re the push =pull woofers ,
( a classic VINTAGE design ! )
Allison said : "The Push-Pull Design used in the IC10 Speakers is used to reduce second harmonic distortion. The results are typically a 10dB -20dB reduction of distortion in the second harmonic."
they are electrically OUT of phase but acoustically IN phase !
some reviewer said
" Because of the system’s unusual woofer configuration, we were especially interested to check the low-frequency distortion. With a constant drive level of 2.25 volts (equivalent to a 90-dB SPL at 1 meter), the distortion was only 8 percent at 20 Hz, 2.5 percent at 40 Hz, and between 0.5 and 0.7 percent from 60 to 130 Hz. This is exceptional performance for a pair of 6-inch drivers and seems to confirm the merit of the push-pull design."
( they were testing the AL125 the AL 130 have 8 " woofers )
As for the rest of the speakers
AL series :here is ol' Roy himself explaining WHY the conVEX cones work
Lander: "You also designed the midranges and tweeters that your speakers used."
Allison: "Developing midrange and tweeter systems that were high enough in quality to complement the woofer we anticipated making was much more difficult. I worked out a configuration that I thought would produce extremely wide dispersion, which I deemed essential. I always wanted maximum dispersion of energy at all frequencies, and preferably the SAME amount of energy at all frequencies, and I set about to get it. That resulted in what was then a UNIQUE DESIGN for a tweeter-and-midrange configuration: what is essentially half a pulsating sphere. When you make it flexible—from paper—and clamp the outer edge to the mounting plate, then drive it at the midway point, the surface of this driver is going to be forced to change its radius of curvature so that there's a relatively large component of motion at right angles to the voice-coil as well as in line with the voice-coil motion."
Lander: "And this gave you the dispersion you were after. Do you still favor paper cones?"
Allison: " Yes, I do. Not for a woofer, where the material doesn't matter very much as long as it works like a piston.
At the other end of the spectrum, I don't want it to work like a piston, because even a small tweeter, if it's big enough to produce any reasonable amount of energy, is going to become DIRECTIONAL at very high frequencies.
So I have to use a very flexible material, and paper has a nice ratio of stiffness to sound-energy absorption when it flexes.
With the right configuration and density and stiffness, paper can behave in a UNIQUE way. It's aided in my design by the material used to clamp the outer edge to the mounting plate—a very thin layer of foam, which is pretty effective in absorbing any energy that wants to reflect back from the edge and cause nonuniform response.
I had emphasized dispersion in order to re-create as best I could the performance-hall ambience.
I don't want to put up with a sweet spot, and I'd rather have less dramatically precise imaging but a close simulation of what you hear in a concert hall in terms of envelopment. For that, you need reverberant energy broadcast at very wide angles from the loudspeakers, so the bulk of the energy has a chance to do multiple reflections before it reaches your ear. I think pinpoint imaging has to do with synthetically generated music, not acoustic music—except perhaps for a solo instrument or a solo voice, where you might want fairly sharp localization. For envelopment, you need widespread energy generation."
Lander: That could explain why your Allison Acoustics speakers met with what you admit was a mixed response. You've also speculated that their appearance, which I've always liked, put some people off.
Allison: "They looked unusual. People didn't expect speakers to look like that, and unconventional things can create suspicion."
Photo another pair of AL130 i bought sadly the former owner replaced the blown allison midrange w/ some bogus AR mid !
note that MOST modern speakers due to the severe limitations of concave cones and design have a NARROW sweet spot ! which makes placement and alignment critical they get more energy directed at a listener so can skate w/ lousy efficiency and low-powered receivers but the system only really sounds good in a limited seating area . but that is the current fashion ( or is it poor design ? cheaping out on materials , hardware ? )
Rising contributor
