BTR-2 (EMI) 1952

In the early days of magnetic recording, steel tape was used in studios, machines such as the blattnerphone’s (1930) and the Marconi-Stille (1933 – 1937) where used however were very large and dangerous to operate in 1947/8 the EMI BTR-1 was introduced, a reversed engineered Magnetophone which offered superior results, 4 years later, the EMI BTR-2 was released in 1952. The BTR-2 was a large step forwards over the BTR-1, the electronics allowed for improved frequency response, longer run time and with the introduction of a relay system, remote control which in the professional world was very important. These machines played a big part in recording studios, BBC and international studios as being one of the first professional machines available to offer outstanding results, Ampex, leevers Rich, Ferrograph and other manufactures were also available at the time, Ampex being the other company to reverse engineer the Magnetophon to create the 200A.

These machines were revered in the BBC as being the Rolls Royce of recorders, they were easy to edit on, in fact the BBC development department modified these recorder to the RD4/4 when Stereo came around and transistors where becoming common, the transports of these machines after 20 years of service showed little wear.

Important features over the BTR-1 was that these machines where completely modular, including the deck, the motors where improved and moved from the bottom of the recorder and housed in the tape transport unit, thinks like the front panel can be removed by unplugging 3 plugs rather than unsoldering many wires, as standard, the BTR-2 is twin speed ( 15-30 or 7.1/5-15IPS), auto follow system would mean as one machine stopped, the next started, it also has a large VU or PPM meter ( depending on configuration) which would monitor the input or output unlike the BTR-1 which only monitors input.

This particular machine is quite unique, after speaking with an engineer from Abbey Road studios, I have discovered that this is an “in house” EMI studio recorder as it has their REDD.18 replay unit ( used thought EMI internationally), but it also has EMI’s tape feeder arms designed to keep tape pancakes smooth, currently, the only studio known to have these on them is Abbey Road, the seller of this recorder ( as well as a second) claimed his father brought them from “ the sale of the century” when Abbey road sold off many of their machines, later on I have discovered the BTR-2 machines Abbey road and EMI archives currently have are not those of their studio but BBC variants and it is possible these two machines actually came from Abbey Road Studios, my investigations are on-going.

The BBC had their own requests for the design of these machines, as far as I am aware, EMI accommodated the rotary 4 pole power switch ( instead of the toggle switch), which allowed 2 separate phases to be switched, the recorders electronics and spooling motors where on one, the capstan and NEON where on another, they also included a second switch for “local or remote” selection, making the front controls inactive whilst in remote mode. Apart from the two rotary switches, the “monitor gain” was replaced with a half moon “rep fader” and the record level replaced with “rec gain” which instead of being a smooth rotary control, was stepped and both controls used the Painton fader mechanism. The BBC variant had one other modification, the ability to use 7 inch reels, a switch was added which placed a large dropper resistor over the play function spooling motors to reduce the talk, this didn’t have an effect when in spooling mode, the standard machine didn’t have such a feature.

Though the BTR-2 was an international success in the studio market, very few of these survive today, manly down to their huge size and being mono ( though the BBC converted them to Stereo), by the 80’s, these machines found themselves in tips around the world as Studer, Ampex, Scully, Otari, Tascam and many more flooded the market with superior stereo machines. Although EMI did develop the BTR-3 recorders intended to handle 1-4 tracks ( stereo was only made), they were in very small numbers, thought to be used in house only, the BTR-4 came along but was not very popular, another machine which was intended to record 4 tracks, this machine was never made either.

It has to be said, the BTR-2 is a personal favourite of mine, with a number of these machines in different formats in my workshop. Though I have discovered issues with transformers going short between the heater and HT windings, after a good service and a lot of capacitor replacements, these machines function very well. Machines I have include basic models which used a VU meter and had no PPM module or PA module, ones with black faced BBC PPM’s ( scale 1-7), white faced EMI PPM’s ( Scale -40 to 15dB), transportable 2 box units and what’s thought to be a prototype BBC modified machine with a black faced front control panel.

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