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Vintage threads from the first ten years

previous: Pat F What are doped speakers? ... -- 8/17/1999 1:51 PM

Re: AC-30 Ghost notes - still....

8/17/1999 2:30 PM
SpeedRacer	Re: AC-30 Ghost notes - still.... "Dope" refers to doping the cones.. All cones are dipped, but many cones also have a rubbery doping compound applied to them (look at the outer perimeter of a Vintage 30 for instance - it's that dark stuff). A cone is a transmission line (signal starts at the coil and propagates to the edge..) and sometimes the nodes in the cone need a little something extra to dampen them (ridges go a long way but..) so you can dope the cone to trim the response. One rumor I heard a lot was that Matchless removed the doping on the V30 speakers they used. I don't know if that's true or not..

8/17/1999 2:30 PM

SpeedRacer

Re: AC-30 Ghost notes - still....

"Dope" refers to doping the cones.. All cones are dipped, but many cones also have a rubbery doping compound applied to them (look at the outer perimeter of a Vintage 30 for instance - it's that dark stuff). A cone is a transmission line (signal starts at the coil and propagates to the edge..) and sometimes the nodes in the cone need a little something extra to dampen them (ridges go a long way but..) so you can dope the cone to trim the response. One rumor I heard a lot was that Matchless *removed* the doping on the V30 speakers they used. I don't know if that's true or not..