On 28/06/2012, Tom Fine wrote:

> Hi Don:
> This makes sense. I re-listened to the Beecham example on headphones
> and I agree there is some stereophony to it, and the perspective you
> suggest matches the sound quality I hear. My bet is, two relatively
> close-spaced mics, probably not omnidirectional in the modern sense,
> so you are getting a somewhat "binaural" effect but not what we think
> of as modern stereophony of a symphony orchestra.
Blumlein's whole approach was to use a crossed pair of directional mics.

This can be extended to four mics for Ambisonics.

I'm not sure I would describe spaced omnis as more "modern" than
crossed-pair. They are alternative techniques. The Decca Tree is a kind
of compromise between the two.

I have had people insist that it is impossible for spaced omnis to give
"true stereo". 

> It actually sounds quite good on headphones because the groove noise
> on the sides is easier to ignore. There are depth and height cues
> around the orchestra, which is a mark of stereophony. To my ears, the
> Bell Labs experiments produced symphonic stereophony more in the
> modern sense, but Blumlein definitely achieved something akin to what
> was called "binaural" in the early days of 2-track duped tapes.
> I wonder, did Blumlein monitor with "earphones" and did the Bell Labs
> guys have two monitor speakers? I've seen photos of the Bell Labs guys
> with "earphones" but I'm wondering if they also had speakers as their
> final reference?
> By the way, speaking of monitoring symphonic recordings, in all photos
> I've seen of Mercury, RCA, Columbia and Capitol/EMI American recording
> sessions from the "golden era," monitoring was always done with
> speakers, in a room isolated from the sounds of the recording venue.
> Mercury and I think Everest monitored in 3-channel, right off the
> 3-track tape/film. Photos I've seen of RCA and Columbia and Capitol
> show 2 speakers, so I assume their recording boards allowed for a
> 2-channel monitor mix. I think Mercury was unique in using a truck as
> the "machine room" rather than just a transport vehicle.
Didn't the BBC use trucks for outside broadcasts from early on?

Don Cox
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