|Radford Studio S.90
Note: a new Radford Forum is now on-line as well as a resurrection of the Radford brand
A modern reinterpretation of this Classic TL is also under development.
information from a Radford Leaflet
|"A floor-mounting loudspeaker of suitable height without a stand for optimim listening satisfaction. Uses same units as the MONITOR and AUDITORIUM loudspeakers. Bass driver is rear-loaded with an open end acoustic transmission line which extends the flat response down to 30Hz. A loudspeaker with the highest possible performance for medium to large rooms. Provides a clean response over the whole audio frequency band from below to above audibility. Frequency range: 30 Hz - 25kHz. Power handling capacity: 50 watts. Size: 45.5" x 17" x 15" (115 x 43 x 38 cm). Weight: 98 lbs (44.5 kg)."|
<clik images for larger plans with dimensions>
The BD25 is a nominal 10" bass driver with specification probably very close to the Kef B139.
Radford FN11/FN12 Crossover
The Radford S.90 was the 1st commercial loudspeaker based on Bailey's papers. My understanding is that there is a direct relationship from Bailey's work to the Radford to the IMFs.
This is a story i recently ran across... i can't speak for its accuracy, but it rings true. Radford may not have reached the US, but a lot of them made it to Canada.
"Bud Fried was advised by Decca to look into transmission lines. They sent him to Radford who were working on them and intended to import them into the USA when they were in production. Year after year Radforn postponed production. One year Bud had announced the transmission line speakers after Radford had promised to deliver - they didn't. So he sat down with John Wright and they decided they had no choice but to produce their own lines. They started with a KEF concerto kit built into a transmission line. With further work on the drivers and crossover, this evolved into the original IMF Monitor."