"Brian Gaff" wrote in message
...


Are we saying then, that some mono recordings are cut in stereo and that
the engineering is such that they can get the balance badly wrong?

In the UK at least, cutting facilities used a separate mono cutter head..
Both EMI and Decca had lathes fitted permanenty with mono cutters
on which replacement masters for mono material, and also mono singles
were cut.

I suppose this could occur where stereo and mono tracks are being cut on
the same disc. However it gets even worse as it was of course a regular
practice in the bad old days to 'synthesize the stero using echo, delays,
phase and tone changes.


This is a very old can of worms, that you are now re-opening,
Brian:-)

In the 70's due to requirements of the Trades Descriptions Act,
or somesuch, the great minds of the record industry in the UK
decided that, with the exception of important classical archive
recordings, they would release no futher mono material. This
was also of course a great money saver, as it removed the
necessity for duplicity at the pressing plants with two presses
being required for simultaneous pressing of mono and stereo
versions of the same LP.

As you mention, there were some pretty awful efforts at
"electronic stereo" particularly on pop records, the simplest
of which was to switch in BP (bass phase) so that all material
below 100 Hz was common and stayed in the centre and then
equalise the left channel to boost the HF from about 5k upwards
and the right channel to boost the low mids and LF. There
are many variation of this basic ideas, and all of which
sounded pretty hideous.


However, there were other approaches that were
much more accepable, and when switched mono
dropped back into the centre giving total compatibility
with the original mono signal.

There was considerable demand from third party clients
for this work, and the studios where I worked had a
suite specifically set up to cater for it. The method itself
was kept secret:-))

No one claimed or even suggested it was genuine stereo,
but it certainly gave the spatial effect that many people
seemed to want, with the advantage of compatibility if
you wished to listen mono. In digital, the same result
can be achieved more easily but using the same
principles.

I have some "before and after" samples, to which I will
post a link, a) if there is an interest, b) if I can find them.

Regards
Iain