On 3/25/2014 9:38 AM, Tom Fine wrote:
> The Rupert Neve thinking came about because he had designed a new mic
> preamp and was with Geoff Emerick, who was testing it at Abbey Road.
> Neve said that Emerick told him that "something is oscillating,"
> although no one could hear anything. Sure enough, looking on a scope,
> there were oscillations at ultrasonic frequencies. What I wonder is,
> would a sharp-eared engineer listening at high SPLs typical of the 70s
> hear problems with lower harmonics of the oscillation, rather than
> detect the oscillation through skin/ear stuff. In a way, it really
> doesn't matter because sharp ears heard the problem, but it would be
> interesting to know if ultrasonic material is beneficial to enjoying
> music or if frequencies over 20k are mostly trouble and should thus be
> filtered (which is the long-time thinking in most audio circles).
I spoke with Geoff Emerick about this event; se said the piece of
equipment was a new console, that, rather than tell Rupert Neve
something was *osillatig* he said that he told Neve something :sounded
wrong" or peraps was *ringing*. Neve investigated and discovered that
some channels of the console did not have proper terminations on their
transormers and were, indeed, ringing. Now, an improperly-terminated
transformer can have all sorts of anomalies in the high frequencies,
some of which manifest themselves as frequency and phase errors in the
audible range. I'm not one to disparage Geoff Emerick's ears -- I have
the utmost respect for them. But his report of hearing "something wrong"
may have come from anomLies within the audible range, not above it.
Peace,
Paul
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