Something different

Dedicated to those large boxes at one end of the room
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jack
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#1 Something different

Post by jack »

I'm researching my wife's great grandfather who, amongst many other things, made radios in the late 20s and early 30s and was one of the original BBC shareholders.

Just got a copy of an advert in the "The Northern Radio & Cycle Supplies" (Darlington) catalogue from 1930-1931 - see enclosed.

GBP 6.10 in 1932 was nearly 3 weeks wages and is the equivalent to about GBP 1,000 now (depending on how you calculate it).

So things don't change.

Ho, hum...
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Lamplugh Speaker.jpg
Vivitur ingenio, caetera mortis erunt
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IslandPink
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#2

Post by IslandPink »

Wow - a moving iron speaker .... perhaps it's time for the idea to be resurrected :D
....perhaps not, it's hard to see it working well at HF, with the mass of the metal on the coil .
"Once you find out ... the Circumstances ; then you can go out"
chris661
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#3

Post by chris661 »

The PA world is seeing some moving magnet designs in subwoofers. With the voicecoil immobilised, you can bolt a proper heatsink to it, and really stick some power through.
Of course, to get around the large moving mass of the magnet, they use really big cones to get efficiency back up. We're talking 30" and up. Impressive, but not commonplace just yet.

Chris
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