[mike s]

On Saturday, June 11, 2011 11:04:53 AM UTC+1, Phil Allison wrote:
"Iain Churchus"
"Phil Allison"
In 1951 in the UK, there were no FM broadcasts, no stereo and the just
about the only records available were 78rpm and pickups were crude to say
the least.

just about the only records available were 78rpm and pickups were crude
to say the least.

Not quite, Phil

10" LPs had been available in the UK since 1951,


** So did the chicken or the egg come first ?

In any case, the performance of the early LEAK and QUAD hi-fi amps were
orders of magnitude ahead of the signal sources available to non
professionals in the early 1950s and for much longer.

In fact, the same amps are not out of place in a modern domestic system -
if fully restored to their past glory.

THD figures of 0.05% and s/n ratios of - 97 dB are still excellent and
better than most sources.

Did Harold and Peter fully realise how far ahead of the game they were ??



.... Phil

I have copies of just about every Wireless World magazine from 1934 to 1952.. It's quite apparent that there was a great deal of interest in, and debate of high quality broadcasting and recording was significant at this time - despite a rather significant war.

High quality recordings and magnetic pickups were available -

http://en.wikipedia.org/wiki/Decca_Records#ffrr

Recording and broadcasting often used very high quality ribbon microphones and amplifiers. And of course the UK and US not having tape recorders until after the war (captured from Germany and Japan), the distortion resulting from copied recordings was absent.

AM broadcasts were often very wide bandwidth and during the day were apparently very good. Leak, Quad and others produced high quality AM tuners. Hobbyists also built high performance receivers -

http://mike.wepoco.com/Home/wireless...odial-ac-super

Some also used tuners for the FM TV audio - where is was available.

Something that was known then, and sometimes seems to be forgotten today is that how an amplifier behaves between 100Hz and 10kHz is crucial. The very low and very high frequencies add to the sensation but if you don't get the range that the human ear is really best at - delivered with the highest fidelity (humans tend not to be able to detect less than a couple of percent of THD) then give up!