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[ARSCLIST] message from Rod Stephens
Rod is having mail-server issues and is unable to post to the ARSC List. He
asked me to post this to button up this thread.
>From Rod:
Hello All,
I hope that this will finally be posted; I've tried a number of times, but
hasn't come up. I hope it's just a matter of changing servers. I wish
Peter and myself good luck.
Peter and I have been having an off list conversation about the 1953 (got
the year right this time) Coronation of Queen Elizabeth and his attempt to
create a stereo version from the multiple audio sources recorded at that
time. I asked his permission to share it, since his insight into the
process has historical significance.
Rod Stephens
> -------- Original Message --------
> Subject: RE: Coronation Recordings [3]
> Date: Thu, 27 Oct 2005 15:39:36 +0100
> From: Copeland, Peter <Peter.Copeland@xxxxx>
> To: Rod Stephens <savecal@xxxxxxxxxxxxx>
>
>
> Due to more mismanagement of my time, I'm now back in the British Library
Sound Archive two days after reading and replying to your message! If you
really think ARSC members will appreciate it, I have no objection to your
posting it; I have now "slept on what I wrote", and can find no objections.
The only new can of worms is that I know EMI (or whatever it's called this
week) have published the Coronation recording on CD, probably a double
album. So far I haven't managed to pick up a copy.
>
> Best wishes, Peter
-----Original Message-----
From: Rod Stephens [mailto:savecal@xxxxxxxxxxxxx]
Sent: 25 October 2005 18:39
To: Copeland, Peter
Subject: Re: Coronation Recordings [3]
> Copeland, Peter wrote:
>
> Dear Rod,
>
> After the lapse of nearly a month and a few seconds' further work on my
project, I can say the following about how the Coronation was recorded.
>
> E.M.I made their own professional tape recorders. The Coronation was
right across the changeover between their BTR1 and BTR2 machines.
>
> The only experience I have of a BRT1 was when I started working for an
outfit called The Christian Broadcasting Commission in Liss (near the county
borders of Hampshire, Sussex and Surrey). That organisation had been given
some tons (literally) of recording and other audio equipment, which the BBC
had found redundant.
>
> There's no doubt that when everything worked well, the BTR1 could get
the most out of contemporary recording tape. But it was a pig to set up,
because (a) it was an oxide-out machine, and (b) because the preset
screwdriver adjustments for setting the H.F (say), altered the gain at 1kHz,
so you needed an oscillator which could switch between two frequency bands,
and switch it once a second or so, to get the response flat!
>
> This may have been okay for the senior engineers at EMI Studios; but
everyone else was pleased when the BTR2 came along. I'm prepared to admit it
may have been *over*engineered! But its advantage for radio work was that
if any one valve (U.S. "bottle") started failing, you were given switches to
find out which one it was. And I had to pass a "simulated emergency" test at
the BBC when I did my first engineering exam there in 1961.
>
> I would guess that when EMI recorded from their landline, they would
have used two pairs of BTRs, one from each landline. By 1953 the CCIR
characteristics for audio tape (at 15ips and 30ips) were in use everywhere
in Europe (except the UK Decca Record Company, who had to "talk to" US
Decca).
>
> At Westminster Abbey, the BBC would have been on-site (in the vestry)
using OBA/8 amplifiers. This was a wonderful Outside Broadcast Amplifier,
with one gain-block about a foot each way and nineteen inches wide, and a
very sophisticated "main gain" control (a stud fader) which also altered the
feedback. So the thing could handle dynamic ranges of anything between
zero-level and about -95dB with respect to the Post Office landline level,
which was 0.775v RMS into 600 ohms. I used to own an OBA/8, but have just
donated mine to the official BBC museum!
>
> The OBA/8 was preceded by any number of passive mixers called MX/18s,
which put series stud-resistances into passive mike cables, and actual
practical mixing (in this case little more than changing from one mike to
another) would be done on the MX/18s.
>
> There were four pots on each MX/18, and I would guess the Coronation
would have needed about six or seven MX/18s for all the mikes, two feeding
two OBA/8s. Two mikes would have been rigged at each location, each fed to
an MX/18 by different cables (no multicore in those days).
>
> Also everything downstream was in duplicate. There would be two "music
lines" (high fidelity analogue phone lines) and two "control lines"
(telephone lines so that the location engineers and the Broadcasting House
staff could keep in contact). The OBA/8 had switches so that if a fault
developed in either the music line or the control line (on an ordinary
broadcast), they could be swopped.
>
> But this wasn't an ordinary broadcast! The sound was also fed to the
infant BBC Television Service (through something called a Trap Valve
Amplifier), a zero-gain device which would effectively insulate the audio
kit from anything television might do!
>
> All the mikes would have been passive. (There was nothing in those
days which had a "head amplifier".)
>
> Most outside broadcasts were done with omnidirectional moving-coils, and
most of these were British-made versions of American mikes. (We called one
"the apple-and-biscuit" or the S. T. & C 4021, whereas I believe you call
the same mike "the high-ball"). It is just possible the BBC-designed AXBT
ribbon mike would have been used for the orchestral sound. This was a
development of the original RCA ribbon made by Marconi in England, and it
had just been re-engineered with higher-energy magnets. The resulting
combination of the mike (called an "AXBT") and the OBA/8 had the best
power-bandwidth product of any audio system at that time.
>
> I consider it extremely unlikely that any "cutters" were used, not
even for current-affairs work. But here is a diversion: I went to the BBC
External Services at Bush House when I joined, and disc recording still
accounted for about half the recording work there, because you could *see*
the sound on the disc, and pick bits out! It is always possible that
something like the Malay Service would have used discs for the Coronation.
Remember, Malaysia was part of the British Empire at that time!
>
> But to answer your implied question : E.M.I transferred from tape to
disc using Scully lathes, with either Westen Electric 2A cutterheads or with
the weird RCA head with its sacrificial overloading system (to compensate
the non-linearity in the armature). The BBC transferred the tape using its
dreadful Type D machines, which had been developed rather hurredly for the
1951 Festival of Britain. (The American Presto machines were much better,
but they were never mentioned in cases of national pride). I actually used
the Coronation recordings to research my IRSC paper on the BBC's
equalisation practices!
>
> As for 50Hz mains hum, I doubt it would ever happen. 10125Hz from
television linescan maybe; but 50Hz hum would be almost impossible with that
kit.
>
> Best wishes,
>
> Peter
>
> peter.copeland@xxxxxxxxxx
>
>
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Rod Stephens (Stephens' Audio Video Enterprises) <savecal@xxxxxxxxxxxxx>