Thanks, Martin Usher!

What you said makes more sense than anything I've seen so far!

Back in the late 50s when I was involved in early computers (air-
conditioned rooms filled to capacity with hundreds of valves 
{tubes}!) my boss, Cyril Hardy  was a friend of Briggs, the founder 
of Wharfdale. This was at a time when I spent the week earning my 
bread, and the weekends being a general dogsbody at Michael Thomas's. 
My boss had built an amplifier using only triodes with PX4 outputs.  
The sound was magnificent using his 1930s Rice-Kellogg bass speakers 
and Wharfdale mids and tweeters.  I believe (though I'm not certain)  
Briggs invented the idea of separate speakers and crossovers.

Anyway, great article Martin!

Best!

Peter Redstone
http://www.ctg.net/redstone