In article , Dave Plowman (News)
wrote:
In article , Phil
Allison wrote:
** The beginnings of hi-fi audio occurred in the 1930s, in relation to
film sound. The need for decent sound quality in cinemas spurred the
development of large single ended & push pull amplifiers using triodes
plus two way, horn loaded speaker systems using 15 inch woofers (often
with field coil magnets) and multi-cell tweeters.

Not sure that is the full story. Optical sound tracks had a restricted
bandwidth and high distortion. Far poorer than possible with even 78 rpm
records.

But it may well have been the main reason for the design of powerful
power amps and speakers.

Reading old issues of WW from the mid 1930's onwards gives me the strong
impression that domestic 'hifi' in the UK initially grew mainly out of the
earlier interest in having 'better' radios (and radiogrammes). Armstrong
seem to have been an exemplar for this by starting off selling 'chassis'
sets aimed at enthusiasts wanting better radio listening and then adapting
to go with the changes as the market developed into 'stereo systems' by
about 1970.

This may be why collectiors of old radios seem often unaware of Armstrong.
They didn't make complete sets in cabinets ready to go. The user had to
sort out a cabinet, and often also the loudspeaker, for themself. In
addition, many chassis lacked the maker's name, or may have been OEM
branded for someone else!

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html