Tag Archives: BBC Microphones

BBC Engineering Training Manual. MICROPHONES. (1951)

I was born on January 20th 1951 at St Mary’s Hospital for Women and Children in the centre of Manchester,  just across the road from the Palace Theatre. Less than a mile away, at the BBC Studios in Piccadilly, engineers were avidly thumbing through their copies of the very latest BBC ENGINEERING TRAINING MANUAL . MICROPHONES!

BBC Training Manual 1951

My copy arrived yesterday! (courtesy of eBay). It is in nearly new condition and sadly it’s unmarked pages have all the ‘vibe’ of a book that has never been read!

In recent years I have often regaled students with my reflections on how much audio technology has changed during my lifetime. Reading through this book really brings it home! It is a window into a long-gone world of engineers in brown lab coats and announcers at the microphone in evening dress. For me, as a child, it was the world of ‘Listen with Mother’ and ‘Children’s Hour’ and seeing the valves glowing in the back of the mahogany veneered wireless set on a shelf next to the fireplace in our living room.

My earliest memory of a microphone was standing on a box in front of a huge Marconi AXBT ribbon mic having won a prize in a BBC Children’s Hour competition at the age of 7 or 8. (It looked just like a giant ice cream cone!) I was presented with a silver propelling pencil by the producer Trevor Hill. I said ‘Thank You’ in the general direction of the mighty Marconi, and was escorted back to my seat.

BBC Children's Hour Competition Prize 1958


Anyhow, back to the book. 

What is most striking is how slender this volume is (114 pages). Most of it is taken up with detailed information about the propagation of sound and the physics involved in microphone design and construction. Much of this is still useful knowledge. However, only 7 different microphones are described in detail and most of these had already been in service since the mid 1930’s.

Here, (to give you a flavour of this informative little book) are some of the illustrations.BBC Marconi Ribbon Mic

In the BBC Studio of 1951 the Marconi AXBT Ribbon Microphone (first introduced in 1935) was the principal tool for drama, announcement and music. Broadcasting  was in Mono. With a frequency range from 20Hz-16 kHz, this figure of eight device was very often the only mic used!  One useful piece of advice offered to the engineer, in order to avoid ‘an excessive bass response’ (caused by proximity effect), is that ‘The microphone should never be used at a distance less than approximately two feet.’


BBC STC4017C

From 1938 to 1953 the STC 4017C was the main BBC outside broadcast microphone. Built like a tank, with a solid copper body and an aluminium diaphragm, it was a very robust dynamic. Although, in theory omnidirectional, it did exhibit some frontal directionality at higher frequencies.


BBC STC4021

The STC4021 , nicknamed the ‘Apple and Biscuit’, was a high quality dynamic mic which, due to its spherical shape, was truly omnidirectional. It was mounted vertically and was used for a variety of purposes including ’round table’ discussions and interviews. It was also used as a talkback mic.


BBC EMI Moving Coil

Developed by Holman and Blumlein working for the Columbia Gramophone Company (later E.M.I.) , it was used extensively by the newly formed BBC Television service at Alexandra Palace from 1936.The unusual thing about this microphone is the fact that it’s diaphragm is made of thin balsa wood enclosed between two sheets of aluminium foil! Interestingly, the description in the book ends with something of a warning……..  ‘the instrument is less suitable when high quality is a major consideration’  !!!!!


BBC Marconi Condenser Mic

BBC Marconi Condenser Element

The Marconi Condenser Microphone with built-in amplifier was a large and extremely rare beast, introduced experimentally in the mid-1930’s.  Even at the BBC it was not commonly used. Early condensers were prone to suffer with crackling caused by moisture.When it was employed it was mostly to be found at concerts.


BBC Brush Crystal Mic

BBC Brush Sound Cell

I have never seen a BBC studio picture with one of these. Not sure what it’s duties might have been. Perhaps, included in the manual simply because it is an example of a crystal mic? These were quite common at the time as PA and announcement mics. Also quite popular with amateur tape recordists.


BBC Marconi Lip MicBBC Marconi Lip Mic Back view

The Marconi Lip Ribbon Microphone (designed by the BBC in 1937) is a noise cancelling device which was used for sporting commentaries and broadcasting in noisy environments. It was designed for very close speaking with the ribbon protected from the impact of the speaker’s breath by the enclosing magnet. (see pics above)  One of the most important features of this microphone is the mouth-guard, which is pressed up against the speaker’s jaws, thus maintaining a constant distance between the mouth and the ribbon. This ensures against changes in frequency response, and volume, caused by fluctuations in distance. A variation of this microphone is still made today for the BBC by Coles (formerly STC).

BBC Training Manual 1951012BBC Training Manual 1951013

Foot Note.

In 1953 BBC Television broadcast live the Coronation of Queen Elizabeth II. Amongst the most notable features of this historic broadcast was the commentary delivered by Richard Dimbleby inside Westminster Abbey. The microphone used on this occasion was the latest Marconi L.2 Lip Ribbon mic. The perfect choice! The closeness of the speaker to the microphone, and the rich tone of Dimbleby’s voice, served to give the listening audience an intimate, sense of the grandeur of the occasion. The isolating characteristics of the lip microphone also served to focus attention on his voice. Dimbleby was the undoubted master of this technique of close-mic’d delivery which became a hall-mark of British State occasions.

Richard Dimbleby at the Coronation of Elizabeth II 1953

Richard Dimbleby with the Marconi L.2 Lip Ribbon microphone in the specially constructed commentary box in the Triforium of Westminster Abbey


 

In Conclusion

Within a decade of this manual the BBC microphone cupboard would be rapidly filling with exciting new models from the likes of AKG, Sennheiser and Neumann. In the following years alongside the growth of television and multi-track recording came a whole range of microphones designed for different purposes. Stereo mics, shotgun mics, lavaliers, parabolic, contact, binaural, ambisonic…………….. A whole new world!


Here are some useful links for more information.

http://www.coutant.org/bbc/index.html   (Some great photos of the Marconi Ribbon Mic)

http://www.coutant.org/marconi/    (Pictures and information on this extremely rare condenser mic)

https://martinmitchellsmicrophones.wordpress.com/2013/06/21/stc-4017c-dead-or-alive/

 

Grampian DP4 (circa 1963) A trip down memory lane!

It was the mid 1960’s and I was a teenager at school in Manchester. Only 30 miles from Liverpool. Before the age of discos. It was a fantastic time for live music. The Mersey boom was at its height and the pubs and clubs were rocking to the latest beat groups. (It is worth noting that none of the music clubs such as The Cavern in Liverpool, or The Twisted Wheel in Manchester, were licensed to sell alcohol. Nevertheless on a Saturday night their subterranean vaults were crammed with teenagers who had often queued for hours to see their favourite bands!)

In the 5th form some of my school mates formed a group. I used to lig along to their rehearsals in the school music room. They had a couple of Vox AC30 guitar amps and an old Selmer which was used for PA. I can remember the singer turning up one day with a very shiny new microphone. All black enamel and chrome, like the headlamp on a classic British motorcycle.Grampian DP4  Removed from it’s bright blue box the mic was duly plugged into the Selmer amp. The lads then launched into their version of Buddy Holly’s ‘Peggy Sue’. The assembled hangers-on (including myself) thought it sounded amazing!

I was therefore overjoyed a few weeks ago when a friend kindly gave me this bright blue box. I recognised it straight away!Grampian DP4 Box

Grampian DP4 with clip

Just below the chrome bezel there is a ribbed rubber ring designed to prevent the mic rolling off flat surfaces. Brilliant feature!

If you buy a DP4 make sure it comes with the 2 pin mic connector as these are as rare as hen's teeth!

If you buy a DP4 make sure it comes with the 2 pin mic connector as these are as rare as hen’s teeth!

Grampian DP4 Label

Here in the UK although the Grampian DP4 enjoyed a good deal of popularity as a PA microphone, and also with amateur tape recording enthusiasts, it was never really thought of as a top quality professional instrument. Sennheiser had launched it’s superb MD21 in 1953 and followed it in 1960 with the MD421.  Around the same time AKG gave us the D19 and the D24. The poor old Grampian was not quite in the same league. However, for a while the DP4 was used by the BBC for outside broadcasts and by their Wildlife Department in conjunction with the Grampian Parabolic Reflector. (As seen on the front cover of this issue of Tape Recording Magazine from 1969 )

tape-recording-uk-1969-04

A few weeks ago on TV I saw an old film clip featuring an impossibly young David Attenborough in the middle of the jungle somewhere clutching a Grampian Parabolic reflector with a DP4 mounted on it.

In the end Grampian Microphones were no match for the German. Austrian and American competition. As the 1960’s rolled on bands got louder, PAs got bigger, stage monitors were introduced and the omni-directional dynamic microphone fell out of use. Cardioids simply had more gain before feed back! By the mid-1970s the Grampian DP4 had disappeared from the stage and eventually the company went out of business.

So what does it sound like? 

 CLICK HERE for a short vocal trip down memory lane!

 

Grampian Brochures and Technical Information (These came in the box with my DP4.)

grampian-dp4-page-1grampian-dp4-page-2grampian-dp4-page-3grampian-dp4-page-4

grampian-dp4-instruction-sheet-page-1028grampian-dp4-instruction-sheet-page-2030

FUN WITH FIGURE-OF-EIGHT! Episode 1 Radio and Film.

RADIO

Back in the 1950s the iconic Marconi AX ribbon microphone was the main tool for BBC drama production.  Actors were familiar with its figure of eight characteristics, and would utilise the dead zones at the sides of the mic to great effect. Noisy page turns could be avoided by holding the script to the side of the mic. The impression of going off into the distance could be achieved by simply delivering the lines whilst slowly moving to the side of the microphone. Shouting from a distance could be managed in the same way. Actors were also very conscious users of proximity effect, moving closer or further from the microphone as the script required.

CLICK FOR SHORT VOICE DEMO.

Figure of Eight Marconi AX                                                             BBC Training Manual 1942

Bearing this in mind an elderly ex-BBC producer told me the following delightful tale about a well- known actor of the day.

Whenever a trainee or inexperienced engineer was spotted entering the control booth he would go through the same entertaining routine. On being asked to deliver some lines to test the mic, he would start speaking in a fairly quiet voice whilst very gradually moving his head round the side of the mic. All the while the hapless young knob- twiddler in the control booth would be increasing the gain on the input. When our actor judged that the gain was almost certainly up full he would deftly swing his head back to the front of the mic and inquire in rich, thespian tones, (as if addressing the back row of the gallery)                            ‘HOW’S THAT FOR LEVEL?!!’

 

FILM

In the early days of talking pictures, years before the invention of the shotgun microphone, considerable use was made of the directional characteristics of figure-of-eight ribbon microphones to minimise the pick- up of unwanted noise on the set.  Cameras and other noisy equipment could be positioned in the dead zones. This greatly improved the quality and intelligibility of the end product. It also made it possible (using more than one microphone) to balance the levels of different performer’s voices. This had not previously been possible using Omni-directional models.

Filming in locations with high levels of surrounding ambient noise, a figure-of-eight could be suspended horizontally above the actors’ heads. The back of the mic faced upwards (away from the sound sources) and the front faced downwards towards the actors. In this position the dead zone effectively attenuated 360 degrees of surrounding noise!

These days, when recording studios seem to be generally stuck in Cardioid mode, I thought it might make a pleasant change to revive some of these vintage figure-of-eight techniques. In the following episodes I shall take a look at more uses for this versatile but somewhat neglected polar pattern.

 

How did Lavalier Microphones get their name?

Potted History Lesson

Lavalier or Lavaliere or Lavalliere is a term used by the jewellery trade. It usually refers to a particular type of pendant, consisting of a large jewel hung on a chain around the wearer’s neck, that is said to have been popularised by either:-                                                                                                                                                    a) La  Duchesse de la Vallière (1644-1710), a mistress of King Louis XIV of France,                                                                                                                                                        or                                                                                                                                                             b) the French actress Eve Lavalliere  (1866-1929).

Hence, it is easy to see why the blossoming film and television industries, in the mid 20th century, came to borrow the term and apply it to a small personal microphone hung on a cord around the neck of the actor or presenter.

By the 1950’s American companies such as RCA , Electro-Voice, and Shure made a range of purpose built Lavalier microphones. In Europe, AKG and Sennheiser also manufactured a number of very successful models.

Eventually, with the proliferation of miniature condenser mics in the 80’s and 90’s, the old Lavalier microphone on a cord around the presenter’s neck gradually disappeared. Although the cord has long gone, and the new miniature mics are simply held in place with clips or micropore tape, they have still retained the name Lavalier, although these days it very often  sadly gets abbreviated to ‘Lav’.

End of Lesson

Here is a real gem of a Vintage Lavalier from the late 1960s the AKG D109

AKG D109 - The D109 was designed in the mid 1960’s to meet the demands of high quality speech reproduction on television and in film. It was beautifully made, with a sleek nickel plated brass body, and  ingeniously engineered so that it could be used in a number of different ways :-

  • With the Lavalier collar  removed it makes a very unobtrusive interview microphone. Even today there are few omni dynamic interview mics this small (less than 3 inches).AKG D109 Interview mode
  • With the collar in place it can be used as a classic Lavalier hung around the presenter’s neck.
  • It also has a clip on the back of the collar for fixing to clothing.
  • By raising the collar above the microphone grill the high frequency response can be increased to compensate for the mic being positioned on the performer’s chest below the chin.AKG D109 Lavalier
  • With the collar raised it can also be hidden under light-weight clothing.

TECHNICAL INFO

AKG D-109 Lavalier Dynamic 

CLICK HERE for Short voice clip.

1931-32 Cutting Edge Microphone Technology At The BBC. (inc The Voight Slack Diaphragm Condenser ! ?)

1932 Marconi-Reisz

In 1932 Marconi-Reisz carbon mics were still in regular use but their days were already numbered.

The other day I purchased a copy of the BBC Year Book 1933 from my usual supplier (ebay). The book covers the period from October 1931 to October 1932. Inside I found an absolutely fascinating chapter on the latest  developments  in microphones and associated technology heralding the move away from the old carbon mics and  the arrival of experimental condensers and the brand new Western Electric dynamic mic. It also describes an innovative new development in the form of equalisation circuitry for correcting anomalies in the frequency response of microphones. The birth of EQ as we know it today. Exciting times!

Here below I have scanned the whole chapter.

BBC Year Book 1933 Microphones p371BBC Year Book 1933 Microphones p372BBC Year Book 1933  Microphones  p375BBC Year Book 1933 Microphones p376BBC Year Book 1933 Microphones p379BBC Year Book 1933 Microphones p380BBC Year Book 1933 Microphones p381

Here is some more info about the slack diaphragm condenser

BBC Year Book 1933 Microphones p382

BBC Year Book 1933 Microphones p384

With the arrival of the iconic BBC-Marconi Type ‘A’  ribbon microphone in 1934 the somewhat unreliable condensers featured above were gradually phased out.

P.S.

The 1933 Year Book also celebrates the opening of the BBC’s fabulous new art deco London headquarters in 1932.

BBC 1933 Year Book inside front coverBBC 1933 Year Book inside back  cover

The Real King’s Speech!

Every time ‘The King’s Speech’ is re-run on TV I find myself foaming at the mouth and whining-on about the microphones…… or more specifically about the WRONG BBC microphones! This annoys the hell out of my family, and so I thought I would get it off my chest in a blog post!

Don’t misunderstand me, I love the film. Fabulous acting  etc  etc. BUT…………….. The spring mounted carbon microphones that appear throughout, and most irritatingly of all in that final speech, were phased out by the BBC around 1935!!!! Surely the producers knew that? Perhaps they thought the carbon mics looked cool, or more intimidating in the close-ups? Whatever the reason, they are quite simply WRONG!  By 1938 the STC4017C was used almost exclusively by the BBC for outside broadcasting. Indeed here is an uncomfortable looking George VI making a speech in 1938 with a typical array of STC4017s.

George VI 1938 with STC4017c

Also, there would certainly have been at least 2 microphones, as that was standard BBC practice at the time. The lower mic in the picture facing upwards at an angle is positioned to pick up the voice as the speaker looks down at his notes and moves off axis from the main pair. (Chamberlain can be seen with a similar setup declaring war on Germany)

I also found this fabulous Pathe News Reel from 1938.                                            This is what The King’s Speech should have looked (and sounded) like!

Ok rant over! Phew, that’s better!

STC4037A ‘The Stick’ ! (1955- late 1970s)

STC4037A

After years of lugging around the mighty (heavy & cumbersome) STC4017, BBC outside broadcasters must have been absolutely delighted, in the mid-1950s, by the arrival of the 4037! Designed specifically for the burgeoning new medium of television, the STC4037 was a triumph of British understatement! Even by modern standards it is light (260g) and well-balanced, and its slender, tapered, profile feels very comfortable in the hand. Also the black shrivel enamel finish is non-reflective under TV lighting. The 4037 was so beautifully minimal and unobtrusive (and black) that it soon became affectionately known as ‘The Stick’. ‘The Stick’ came in 2 sizes, the 21.3cm long version, the STC4037A, and the shorter 13.6cm STC4037C. The short version had slightly less bass response but was extremely unobtrusive, all but disappearing in the presenter’s hand.

A couple of TV clips from the 1960s featuring the STC4037  :-

Gwyn Thomas talks to Alan Whicker about the Chip Crisis

A great Liverpool band The Undertakers with 4037 on vocals 

The original box arrived a wee bit bruised and battered!

The original box arrived a wee bit bruised and battered!

STC4037A with 4069A connector and stand adapter

STC4069A connector and  PAS45/14 stand adapter

STC4037A Base of mic

3 pin connector on base of mic

STC4069A Connector

STC4069A Connector

 STC4037A Grill STC4037 Brochure 1961

Click Here For Short Sound Clip.

Meanwhile here is another couple of suggested uses!!

STC4037A the perfect kit overhead!

Crisp snare, nice fat toms, and smooth detailed cymbals, and so much bottom end that the kick mic was nearly redundant! Job done!

Here is a short live clip of this kit with the 4037 as pictured.

Also tasty on double bass!