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ISO - SP-1A or CB Int’l compressor

Cabover Bob

Sr. Member
Nov 17, 2020
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Picked up an AR-3500 and would like to find an original SP-1A. It was suggested to me that I might be able to use a CB Int’l speech compressor as an alternative. Suggestions and leads are greatly appreciated.

Todd
 
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I know of a few places selling copies of the SP1a. Lou Franklins CB Int speech compressor is totally different animal. Sp1a contains a compander and CB Int is a series of opamp stages with a feedback loop setup like a clipper. I have both and choose he SP1a for how clean it sounds.
I agree, years ago my bud Tracy, KE6OYE even etched his own version of Lou's board with a couple component changes and the SP1 still worked better.

Just hard to find now.
CPI built a Speech compressor called "Talk Power" that worked well, also hard to find now.

73
Jeff
c074ce356080738be9679557e91a22be.jpg
 
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I agree, years ago my bud Tracy, KE6OYE even etched his own version of Lou's board with a couple component changes and the SP1 still worked better.

Just hard to find now.
CPI built a Speech compressor called "Talk Power" that worked well, also hard to find now.

73
Jeff
View attachment 62345
Lesscomm sells his copy for a 300% markup. I etched my own minus the relay.
 
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Reactions: NZ8N
I know of a few places selling copies of the SP1a. Lou Franklins CB Int speech compressor is totally different animal. Sp1a contains a compander and CB Int is a series of opamp stages with a feedback loop setup like a clipper. I have both and choose he SP1a for how clean it sounds.
Any information on where to acquire one of these copies ?
 
Thank you for that……..
I only mentioned that because @KneeBiter said he would part with one. I haven't one goings into the 797 and the other one for a possible future project. If kneebiter can part with 2 I would say buy them because they're hard to find. I paid more than I should have for the 2 I got but will hopefully be worth it.
 

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