BBC L2 (STC4104 A) Lip Ribbon Microphone Circa 1955

When this BBC L2 (STC4104 A) first arrived, I thought that I might lavish some TLC on it’s battle-scarred wooden case to make it look a bit smarter. However, the more I look at it, the more I think that I shall leave it just as it is. This microphone has clearly been around the block a few times and has history. The two stickers on the lid are REPAIR and TESTED labels from the BBC Equipment Department in the mid 1980’s. By then it had already been in service for 30 years!

I always feel a bit sad when I see a vintage microphone advertised on a selling site as being “Unopened in original box”, or simply “NOS”. No history, just old. Certainly not the case for this BBC L2 (STC4104 A). Opening the lid of the box reveals a microphone which has had a lot of use!

Most high quality microphones spend their lives cosseted, and looked after by skilled engineers, in the well regulated environment of a recording or broadcasting studio. This BBC L2 lip ribbon microphone has spent its life on the road with journalists, commentators and broadcasting crew. What is really amazing is that it is still in great working condition, along with its original 3 position Equaliser.

The only down side to this piece of kit is that the microphone, equaliser, and case have a combined weight of 13lbs! Most of this is the equaliser. Later models dispensed with the EQ. Instead the MED BASS roll-off was built into the microphone. However, it is pretty clear from the big splodge of red paint, that even with this mic, MED BASS was the preferred setting.

History Lesson

The BBC designed the L2 in 1951 as an updated version of the L1 which had been in service since 1937. It arrived just in time to play a starring role in the televised Coronation of Elizabeth II, when it was used to capture the famous commentary by Richard Dimbleby in Westminster Abbey. Dimbleby was known as the “Voice of the Nation”, and so on this occasion the L2 was perhaps the “Ear of the Nation”, into which he delivered his stately measured tones. It was the first mass-televised event in Britain. Shops selling televisions ran out of stock as people bought them for the first time!

(Watch from 3.30m)

The BBC L2 (STC4104 A) also made it possible to clearly broadcast commentary from even the noisiest of environments.

This microphone has an extraordinary ability to cancel out and reject unwanted surrounding sounds. It is particularly insensitive at the sides of the mic in the dead zones of the ribbon.

Here is Kenneth Wolstenholme at the 1966 Football World Cup.

CLICK LINK below to hear the end of the match !

https://www.bbc.co.uk/sport/av/football/27005797

CLICK HERE to hear my STC4104 A in action!

CLICK HERE to hear the STC4104 A delivering a VOCAL. (Great new look for any singer!)

Technical Information

In previous posts I have occasionally (often) moaned about the difficulty of finding information about various vintage microphones. In the case of the L2 lip ribbon microphone, because it was designed by the BBC, there is a wealth of documentation available. Rather than writing a lengthy technical description myself, I would recommend reading the BBC Monograph which appears below. This explains the design and usage of this classic microphone in great detail.

P.S.  Today a version of the BBC L2 (STC4104) lip ribbon microphone is still made by Coles and is widely used by journalists and commentators all over the world.

bbc_monograph_07Download

STC4105A CARDIOID DYNAMIC MICROPHONE (1955- around 1970)

Released in 1955, the STC4105 is a small, black, unobtrusive, dynamic PA microphone, boasting a cardioid polar pattern and a brand new design of plastic diaphragm. Previous STC dynamics were made with aluminium diaphragms which were much more susceptible to changes in temperature and more easily damaged. The 4105 was also the first true cardioid, single diaphragm, dynamic produced by STC. Previous models such as the 4035 were essentially omnidirectional, but with some directionality at high frequencies.

Here below is the original STC4105A brochure with a full description and technical specification.

stc4105-tech-specDownload

BBC or NOT BBC?  

I have often seen it claimed, online (mostly in web forums and on selling sites), that the STC4105 was used by the BBC.  So far, I have found no detailed evidence to support that claim! The National Science and Media Museum here in the UK have one in their collection, which I am told came from the BBC, and the catalogue simply says “Used as hand-held reporter’s microphone”. However, as far as I can ascertain, the STC4105 does not appear in any BBC R&D technical report or in any BBC Training Manual. I can also find no photograph of it in a BBC studio or on an outside broadcast. Indeed, I can find very few period photographs of it in action anywhere! I had been hoping to unearth a wealth of pictures of it on stage with the rising stars of rock ’n’ roll, but sadly all I could find were a few images of British politicians of the 1960’s pictured at conferences. I think that the sad truth about the STC4105 is that although it had a good deal to recommend it, it was not a popular choice of microphone for either broadcasting or PA.

Pictured below.

Labour Party Leader Hugh Gaitskell,  

Labour Prime Minister Harold Wilson and

Conservative Prime Minister Edward Heath. (Loving the look of boredom on the faces of the 3 guys on the left!  Is the bloke in the corner asleep?) Interesting to note that Heath is not addressing the mics and would probably have been better off with a pair of 4035s!

Pricing could have been a factor influencing the popularity of the STC4105.  In 1962 a Reslo RB/L (as used by The Beatles and The Rolling Stones) cost £9.12s. A Grampian DP4 (also popular with young performers) cost £8.0.  On the other hand the STC4105A cost £22.10!  In today’s money that would be more than £500.

So what does the STC4105A sound like? 

CLICK HERE for a Voice Test followed by Kalimba and Rainstick!

Conclusion 

The early 1960’s saw the arrival of exciting, and technically superior models from Germany, Austria and the USA. The days of the STC dynamic microphones, with their limited frequency response, and somewhat out of date styling, were numbered.

However, reading this warning from the brochure;

I can’t help wondering if the fortunes of the 4105 might have been different if   STC had followed their own advice and simply manufactured the mic with a ‘simple windshield’……….Perhaps a wire mesh ball with foam inside?  After all the frequency response is not that different to the Shure SM58, which came 10 years later!

STC 4035 Omnidirectional Dynamic (Circa 1953)

Designed in the early 1950’s and used extensively by the BBC, the STC4035 replaced the STC4017C which had been in service since 1938. Throughout the 50’s and 60’s the 4035, along with its Bakelite cousin the STC4032, were amongst the BBC’s primary outside broadcasting microphones. Apart from the casing and switching on the 4032 these two microphones were identical. Although both models had the same very effective wind resistant fine mesh grill, in the event of very high wind or rain the 4001.A. windshield could be added.

The 4035 was much lighter and smaller than the old 4017, and although it was essentially omnidirectional there was some directionality at high frequencies.

Here is a full description and technical specification.

stc4035-brochureDownload

Below is a pricelist from the late 50’s.

N.B. In today’s money £18.10.0 would be around £520.00.

At the BBC the 4035 was used for a very wide range of tasks.

Big Ben

In the mid 50’s an STC4035 with a modified connector/mounting attachment was installed directly beneath ‘Big Ben’ in the Elizabeth Tower at Westminster. This was connected to BBC Broadcasting House and used to broadcast ‘live’ the world famous clock chimes of this huge, iconic bell. My Dad (along with the rest of the British population) always used to set his watch by the BBC chimes.

Horse Racing

In order to capture the exciting thunder of horses’ hooves and all the thrills and spills of the race, BBC Manchester Radio OBs used to place a 4035 in every jump for the Grand National.

Wimbledon.

1962. Interesting arrangement of two STC4035s with windshields.
(Photo IET Archives)

They were also used as general effects mics at many other sporting, and outdoor events, very often used to pick up atmosphere and the sound of the crowd.

Perfect for Political Speeches

British Prime Minister Harold Macmillan in 1957 (Photo BBC)

STC Dual stand.

ITV arrived in the mid-1950’s and also found plenty of use for the mighty 4035!

1967 Coltishall Airshow AngliaTV:  STC 4035 in a Grampian Parabolic Reflector. (Photo Dave Taylor).

I love the look of dedicated concentration, trying to focus the dish on high speed aircraft using only headphones!

The 4035 connection socket is the same as most STC microphones and requires the 4069A plug (which is still widely available).  Interesting to see the screw heads in this picture. These can be undone to separate the upper and lower halves of the microphone for repair. Normally they are covered with hard wax.

So……. What does it sound like?  CLICK HERE for audio clip.

Conclusion

If there was a competition for the world’s most boring looking, least stylish microphone, the STC4035 would definitely be in the running, with its dull grey/black finish and uninteresting shape. Also, unfortunately, unlike the ‘Apple and Biscuit’ STC4021 or ‘The Stick’ STC4037, the poor old 4035 doesn’t even have an amusing nickname! However, good looks aren’t everything and if you are simply looking for a robust ‘workhorse’ microphone with a reputation for being completely reliable, even in the most adverse conditions, then the STC4035 is definitely worth considering!

Electro-Voice RE20 Cardioid Dynamic 1968- present day.

Picking up the RE20 for the first time the expression ‘built like a tank’ immediately springs to mind. Weighing in at 1lb 10oz everything about this microphone is heavy and solid. Able to operate in conditions of extreme temperature and humidity the RE20 can also handle pretty much unlimited SPL. If I was commissioned to record an erupting volcano, or maybe a nuclear explosion from close quarters this is the microphone I would choose! In addition it also has a wide, flat frequency response, uniform cardioid polar pattern and excellent transient response all of which allows the RE20 to compete with the very best of studio condensers.    

Here below is the manufacturer’s Technical Data and Service Sheet for the RE20 

re20_engineering_data_sheetDownload

pl20-and-re20-serviceDownload

Short History Lesson.

At the tail end of the 1950’s Lou Burroughs, co-founder of Electro-Voice announced that the company was to move away from the manufacture of condensers and ribbons and concentrate on producing dynamic microphones. He believed that condensers and ribbons were too fragile and temperamental and that dynamic microphones were superior in every way. He declared ‘These are the microphones of the future’.

Throughout the 1960’s Electro-Voice developed a series of quality dynamic microphones based on their famous Variable-D design, starting with the EV664 ‘The Buchanan Hammer’ and culminating in 1968 in the now legendary RE20. The advertising clip below for the EV666 illustrates how the Variable-D design uses phase cancellation to reduce unwanted pickup from the rear of the microphone and thereby ‘create a uniform cardioid pattern at all frequencies.’ The most obvious practical advantage is that ‘proximity effect’ is pretty much eliminated. This allows the user to address the microphone from very close quarters without any unnatural rise in bass frequencies.

Right from the start the RE20 proved to be an enormous hit with radio stations, recording studios, PA companies and performers. The RE20 was used for lead vocal on two albums by Stevie Wonder, ‘Talking Book’ in 1972 and ‘Innervisions’ 1973. Producer Robert Margouleff said that the RE20 helped achieve a “close, intimate sound”.  Tracks such as ‘Superstition’ and ‘You Are the Sunshine of My Life’ are outstanding classics of popular music.

Impervious to Popping.

Another important feature of the RE20 worth mentioning here is the internal ‘pop’ filter. Every entrance to this mic is protected by a barrier of thick foam.  I can think of no other microphone like it! For singers, actors and broadcasters who are prone to ‘popping’ or sibilance the RE20 is the solution to the problem. Even from a distance of ½ an inch it is almost impossible to make it ‘pop’!

Here is me being silly just to illustrate the point. 

Soooo…. In Conclusion.

Apart from close up recordings of plosive tongue twisters what else is the RE20 good for? Over the years it has been used for many things. Apart from broadcasting and vocals it has gained a considerable reputation on kick drum, guitar (electric and acoustic) bass (electric and upright) and brass instruments of all shapes and sizes. To be honest it is one of those very rare microphones that will sound great on almost anything!

CLICK HERE for recording with Tenor and Baritone Sax and Kick

Sennheiser MD408 N Super-Cardioid Dynamic Gooseneck Microphone. 1960’s/70’s

Originally designed for speech and vocals the Sennheiser MD408 N is a solid, reliable, workhorse microphone which is useful for many tasks. It performs well on guitar cabs, delivering a rich beefy sound with plenty of midrange punch. The flexible gooseneck makes it particularly easy to position. It is also useful on snare and a variety of percussion. Once again the gooseneck is very handy for manoeuvring in awkward spaces. Being a super-cardioid it also has excellent feedback rejection.

Some microphones were destined to appear with the stars, glittering centre stage with Elvis or Tina Turner or David Bowie. Others however, never quite made it to the limelight. Back in the 60’s and 70’s the MD408 N was often used as a humble studio talkback mic. Even so, when it comes to dull publicity photos the shot below takes a lot of beating!

Sennheiser MD408N Klien Tuchel Connector and standard 3/8 inch stand adapter.

The MD408 also has a silent on/off switch which is very handy if it is used for talkback or as a lectern mic. The neat square plastic actuator has sadly gone missing on mine but you can see it in the publicity photo.

CLICK HERE to listen to the MD408 on rock’n’roll Guitar at a live show.

Conclusion

Whilst it may not have the kudos and charisma of the more famous Sennheiser Models such as the MD421 and MD441 it is nevertheless a recommended addition to any collection.

Tannoy Microphone Circa 1950.

Background.

The Tulsemere Manufacturing Company was founded in London in 1926 by Guy R. Fountain. In 1928 the name was changed to Tannoy. Rectifiers used in the company’s amplifiers utilised an alloy made from lead and tantalum. The name is simply a contraction of TANtalum/allOY.

 In the UK throughout the 1930’s Tannoy built up a considerable reputation for the design, manufacture and installation of industrial public address systems. Tannoy systems appeared in department stores, factories, offices, public buildings, academic institutions and sports grounds. In fact, just about anywhere that public announcements needed to be made- indoors or outdoors. There were even mobile systems fitted to vans!  

During World War 2, Tannoy manufactured installations for the British Army, Navy and Royal Air Force. Orders and day to day communications would be announced over ‘the Tannoy’.

By the end of WW2 the Tannoy brand was pretty much synonymous with any PA system. In 1946 the word ‘Tannoy’ passed into the Oxford English Dictionary as a noun meaning ‘public address system’. This usage is still current in the UK today.

As can be seen on the microphone featured here, Tannoy were not shy when it came to emblazoning the company name on their products. Judging from the tasteful antique bronze and grey paint finish, this gooseneck announcement microphone may well have been mounted on a mahogany desk in a Town Hall or other municipal building.

At first glance I assumed that this specimen, which has no model or serial number on it, was simply a dynamic paging mic in a fancy-looking case. However, when plugged in I was very surprised to hear how good it sounded! I carefully removed the grill and inside this is what I found……………

……. A well-made and neatly constructed, end addressed, ribbon motor. The back of the ribbon is enclosed by the magnet and the rear section of the casing. This produces a pretty much cardioid, directional polar pattern. It is similar in design to the STC4113 featured in a previous post.

So what does it sound like?   Because, here in the UK we continue to be under COVID-19 lockdown restrictions I still can’t get close to any proper musicians. I have therefore put together a slightly eccentric audio ‘collage’ of ‘percussion’ from around my desk to illustrate some of the impressive qualities of this distinctive Tannoy microphone. Marvel at the slightly sinister sound of 2 small terracotta plant pots being rubbed together and check out the creaky floor board! The finest details and complex textures of a variety of sounds are effortlessly reproduced as well as delivering natural speech with a high level of intelligibility.  

 CLICK HERE TO LISTEN.  

Conclusion.

This is definitely a microphone to keep. Apart from vocals and percussion, I have a feeling that it will work well on a whole range of instruments. Ribbons are always great for beefing up guitars! Can’t wait to get back to gigs and try it out!

P.S.  

Here below are a couple of photos of another Tannoy microphone sent to me by Stewart Tavener at http://xaudia.com/. This mic appears to share the same casing and ribbon motor as mine but has a switch and hinged stand mount.

Omnidirectional Dynamic Vocal Microphones

Up until the late 1960’s, cardioid, omnidirectional and figure of eight dynamic microphones were all commonly found in use on public address systems. Singers were able to choose whichever pattern suited their particular style of delivery. Figure of eight ribbon mics, for instance, were enormously popular with the jazz singers and ‘crooners’ of the 40’s and 50’s because of their smooth response and rich proximity effect which enhanced the low end of the voice. Omni was preferred by singers who required a more ‘open’ sound and the ability to move around without altering tone. Unfortunately, with the development of high power PA systems and the introduction of wedge monitoring in the late 60’s, only cardioid microphones had the required rejection characteristics to deliver a suitable amount of gain before feedback. Consequently, within a few years figure of eight and omni all but vanished from the stage and were pretty much banished to the studio!

I recently acquired a number of vintage omnidirectional dynamic mics from the tail end of the last century. Although the primary purpose of these mics was originally news gathering, my attention was drawn to the following excerpt from the AKG Engineering Data sheet for the D130. It perfectly describes the numerous benefits that an omnidirectional microphone offers the vocal performer.

AKG D130 Data Sheet.

A wide-range instrument, the D-130E offers “open”, natural reproduction of speech and music -without harshness, popping or bass emphasis. Moreover, the D-130E ‘s omnidirectional pattern and consequent absence of proximity effect enable the microphone to retain this natural quality -regardless of the relative position or distance of performers working into it. Together with its handling comfort and attractive styling, these same characteristics also lend the D-130E to a variety of hand-held on-camera applications in the studio -especially to pop-free coverage of vocalists who do not desire proximity effect.

Many singers (especially male vocalists) have an uncomfortable relationship with cardioid microphones because of their inclination towards ‘boomy’ bass and unpleasant popping plosives. I have also worked with performers who are in the habit of pulling away from the mic when delivering the loud bits leaving their voices sounding suddenly thin and weedy (N.B. Proximity effect works in both directions i.e. moving away reduces bass). With omni the bass remains constant with the desired reduction in volume.

And another thing………

For performers whose vocal style involves ‘cupping’ the back of a cardioid dynamic, maybe an omni would be a better choice? It comes ready ‘cupped’!

 

 

 

 

 

 

 

So…….. Here’s a thought…….

With the rise of in-ear monitoring many performers and bands are dispensing with their cumbersome (and feedback prone) on-stage wedges. So it would seem to me that for cardioid averse vocalists, perhaps now would be a good time to consider bringing back the considerable benefits of the

Omnidirectional Dynamic Vocal Microphone.

AKG C451E (Circa 1970) A Classic from The Golden Age of AKG

Today AKG is little more than a brand name owned by a multi-national corporation. Like a tired old rock star it rests on the laurels of its former glory whilst still churning out a few old favourites.

However, if we go back to the late 1960’s and into the 70’s AKG was a powerhouse of innovative design and high-tech engineering. Major achievements include the D200 series which took dynamic microphone design to a peak which even today sees few competitors. This period also saw the legendary C12 condenser evolve into the C414 which continues to be a favourite in studios across the world.

In 1969 AKG launched its newly developed Condenser Microphone System (CMS) using audio frequency circuitry with Field Effect Transistors. This was a fully modular microphone system based around the C451E, the inherent features of which were claimed to be;

• Low noise level,
• Extremely high reliability and
• Life-long sta­bility.                                                                                                    

A selection of interchangeable capsules and extension tubes could be purchased along with a variety of accessories covering a wide range of recording and live sound applications. The CMS proved to be enormously popular with broadcasters, TV companies and studios throughout the 1970’s and beyond, and can be seen on many BBC music programmes of the period.

These contemporary AKG brochures/guides explain the features of the CMS in detail.

AKG C451 CMS Technical Specifications

Technical Info AKG CMS microphones.

My C451E

Judging from the old style of logo and the lack of an externally stamped serial number on my newly purchased C451E (see top 2 pics), I think that it must be a fairly early example. It is in perfect condition and even the case is hardly marked. As always it was a bargain!

So What Does it Sound Like?    

Sadly, like many, many other people I am stuck at home at the moment practicing social distancing, and so recording music with my beautiful new C451E will have to wait until the current COVID-19 pandemic dies down and we can all get back to work!

Meanwhile Stay safe!

P.S.   Went for a walk today and recorded this:-    https://www.youtube.com/watch?v=k5MHEL6ZPHI

 

Gaumont-Kalee Type 492 Ribbon Microphone (Circa 1950) A rare piece of British cinema history.

I bought this microphone out of curiosity! It caught my attention because I had never seen or heard of it before (shock, horror!).  It came in its original felt lined wooden box, of the kind normally reserved for valuable scientific instruments. The name Gaumont I recalled from the old UK cinema chain but beyond that I knew nothing.

Researching this microphone has proved to be a challenging task.

It would appear that the Gaumont-Kalee Type 492 was never on sale to the general public. It was marketed along with other Gaumont-Kalee equipment purely within the cinema industry. So far the only contemporary references I have found have been in trade journals such as British Kinematography and Cine Technician.

It was manufactured by British Acoustic Films Ltd (B.A.F.), which by 1947, along with Gaumont-Kalee, was one of the many companies which made up The Rank Organisation.

Specifically designed as a boom mounted microphone, the Gaumont-Kalee Type 492 was most likely used to record dialogue and music for the classic British movies made at The Rank Organisation’s studios in the 1950’s. By this time The Rank Organisation in Britain had become one of the biggest film companies in the world. They owned 5 major studios including Pinewood and Ealing and Denham. Rank also owned and controlled distribution for several hundred UK cinemas.

B.A.F., under the Gaumont-Kalee brand, produced a number of sound recorders for the cinema industry, both optical and magnetic. Below is an advert from Cine Technician March-April 1953. My assumption based on this is that the Type 492 ribbon mic (and the Type 493 condenser not covered here) were designed for use with these machines. A 1947 BBC technical report on The G-K Sound on Film Recorder also makes passing mention of 2 microphones being supplied with the machine.

The Gaumont-Kalee Portable Recording Equipment pictured here features 35mm or 17.5mm sprocketed magnetic film which could be run in sync with a professional movie camera. In post-production this enabled easy editing and transfer.

These days when we talk about portable sound recording equipment we are maybe thinking of something the size of a mobile phone. The ‘portable’ equipment described above would have filled the boot of a car and required fairly muscular crew to carry it! However, its mobility nevertheless extended the possibilities of location recording both for TV and film production. (Also worth mentioning that magnetic film made a considerable improvement to the available frequency response.)

From this advert it can be noted that other users included BBC Television, Universal, a number of Newsreel companies, San Angel Inn (Mexico) and Dear Film (Rome).

 

Technical Information on the Gaumont-Kalee Type 492

In the absence of any detailed manufacturer’s literature, below I have made some observations and speculation about the design of this mic.

Noise has always been the enemy of the motion picture sound recordist, whether it be camera and equipment noise, on-set noise, tape hiss, or electrical interference generated by lighting. Trying to obtain clarity, especially in dialogue, has always been something of a challenge. This was particularly true in the age before shotgun mics.

• In common with all figure of eight microphones the dead zones at the sides of the Type 492 could be directed to minimise unwanted mechanical noise from cameras and other equipment.
• The yellow wiring around the ribbon is cunningly arranged to form a humbucking loop, helping to reject electromagnetically induced–noise. This is very useful when operating in the vicinity of lighting equipment and large mains transformers radiating strong magnetic fields.
• In addition, the interior of the grill is lined with ultra-fine wire mesh which not only provides a certain amount of blast protection and back pressure for the ribbon but also creates an effective Faraday Cage.
• The interesting-looking baffle arrangement on either side of the ribbon has the effect of producing a boost to the high end frequency response. This may provide greater clarity to dialogue, especially when recording at a distance (in order to keep the boom mounted 492 out of the camera shot). It was also common practice at this time to boost signals going to magnetic tape at around 4kHz on the way in and cut by the same amount on playback. This returned the desired signal to flat and reduced unwanted tape hiss by several db.

• The connector pictured above is a Reslo. This mic came with a 3 pin Amphenol. When I took the mic apart it became clear that this was a modification as it was chipped and had been filed to fit! Stewart Tavener at Xaudia informed me that the two 492s he had previously repaired had Reslo connectors. The Reslo fitted perfectly. Thanks Stewart!
• Unlike many of the ribbon microphones of the period which have impedances of 50 ohms or less, this Gaumont-Kalee Type 492 has an impedance of 300 ohms with a strong output signal which requires considerably less amplification than many of its contemporaries.

So what does the Gaumont-Kalee Type 492 sound like? CLICK HERE.

 In Conclusion.

Having emailed academic institutions, museums, collectors and fellow sound engineers all over the world, so far I have only tracked down a handful people who have come across the Type 492. The serial number on mine is 132 and I assume from the complete dearth of information that only a limited number were made. Sadly, much of the recording equipment from that period has long since gone in the bin along with company records, technical literature and drawings. Trying to unearth information about the Gaumont-Kalee Type 492 has highlighted to me the growing problem of vanishing history in the field of audio technology. Living links to the past are dying out and records are being lost. It is therefore important to preserve what we can before it is too late!

NEWS FLASH UPDATE  12 Nov.2019  

   have kindly unearthed this single page ad for the Gaumont- Kalee Type 492 and Type 493  in a May 1951 GB-Kalee product catalogue ‘Everything for the Cinema and Theatre’.  GB Kalee Type 492 Advert 1951

UPDATE 28th Nov.

Stroke of luck! Have just purchased this GB-Kalee Catalogue for 1950 on ebay and here on page 4 are the frequency response graphs for the Type 492 and 493!

Gaumont British-Kalee proudly projects it’s brand across the world! The British Empire is marked in pink. Within a couple of decades the Empire was gone along with GB-Kalee and most of British industry!  (N.B. Even by 1950 the map above was out of date. India got rid of us in 1947 !)

 

Useful Links.

https://www.gettyimages.co.uk/detail/news-photo/an-engineer-works-on-a-laboratory-set-up-to-develop-news-photo/90777079?adppopup=true   Taken at B.A.F. factory at Mitcheldean in Gloucestershire in 1953, on the workbench is a Gaumont-Kalee Type 492. The zeppelin shaped mic up in the air is the Type 493 condenser.

http://xaudiaelektrik.blogspot.com/2014/02/motm-gaumont-kalee-type-1492-ribbon-mic.html  It is interesting to note that the microphone featured here has a 1 inserted in front of the 492. Apart from having an impedance of 50 ohms, what the difference was I have no idea.

1962 BBC Training Manual

In the 1951 BBC Microphones training manual we saw that the corporation functioned with a small selection of British manufactured microphones, most of which had been in service since the 1930’s.  So when I saw this Manual from 1962 I was curious to see how ‘Auntie’ had moved on into the swinging sixties.

Old favourites continued in use.                                                                                         

The STC4021 ‘Apple and Biscuit’ first appeared in 1935 as did the famous Marconi A series ribbon microphone pictured on the page below. (The AXBT is the 4^th generation).  The STC4035 was a lighter, updated replacement for the old STC 4017, which had been phased out in the mid 50’s. The 4032 is identical to the 4035 but housed in a neat handheld Bakelite body making it suitable for outdoor use in all weathers. The 4037 was designed for TV and has a rather more modern look (slim lightweight body and matt black finish). However, the capsule is still pretty much the same as the good old ‘Apple and Biscuit’. STC’s dynamic models were the tried and tested backbone of general purpose and outside broadcasting. The noise-cancelling STC4104 lip ribbon mic was used for sports commentary and noisy events. This was an updated version of the older Marconi lip ribbon microphone. More recently manufactured by Coles, the 4104 continues in production to this day.

So what was new?

FM broadcasting by the BBC began in 1955 and the audio frequency response was thereby extended from 5 kHz up to 15 kHz. The new FM system was also considerably less susceptible to noise and interference than AM. Although the old favourite microphones from STC and Marconi were still fine for everyday transmission of speech, when it came to the broadcasting of high quality music, mics with improved high end response were now required. With this in mind the BBC Research Department designed 2 new ribbon microphones (pictured above). First came the PGS (Pressure Gradient with a Single magnet) and from this developed the 4038. Manufactured by STC these new microphones were considerably smaller and lighter than the old Marconi AXBT, and had an almost flat frequency response up to 15 kHz. This was around ½ an octave higher than the mighty AXBT. Now manufactured by Coles the 4038 continues in service to this day and is still recognised as one of the finest ribbon microphones available.

The photograph below is rather bizarre. In real life the STC4033 is around 3x bigger than the Reslo! The Reslo was small and convenient for use on TV (as mentioned in my previous blog post). The STC4033 is an unusual hybrid, similar in design to the classic Western Electric 639 ‘Birdcage’. It has an ‘Apple and Biscuit’ type omni dynamic element, and a ribbon element. This gives a choice of switchable polar patterns. Using the elements separately we have Omni or Figure of Eight and by combining the outputs of both we obtain Cardioid. Nevertheless, by 1962 the STC4033 was a somewhat antiquated design and no match for the more sophisticated competition coming out of Germany and Austria.

Enter AKG and Neumann……….

A number of high quality condenser microphones now appeared in the BBC microphone locker. The legendary AKG C12 quickly became a firm favourite for the broadcasting of concerts and was very often the only microphone used to capture a symphony orchestra in glorious Mono! The AKG C28, C29 and C30 were perfect for solo performers on live TV. The variable extension pieces made it easy for unobtrusive positioning.

The Neumann KM54 cardioid, and the multi-pattern KM56 were also popular choices for high quality broadcasting.

Other Microphones.

A number of other microphones are given a mention but not honoured with a photo. The Corporation was still very much dominated by BBC Radio and most of these microphones are from the rapidly evolving new world of BBC Television. TV presenters very often needed to keep their hands free and microphones ‘in shot’ needed to be small and unobtrusive.

The Placing of Microphones
The diagrams and explanations on the pages below provide an interesting insight into the lost world of recording and broadcasting in Mono.

The BBC philosophy for the broadcasting of classical music is best summed up in the opening sentence of the page below.  In the manual there is a clear distinction between music which requires the engineer to simply reproduce a ‘true balance’ created by the conductor and the performers (captured by one microphone), and more popular forms of music which require the engineer to create the balance from a number of microphones. Today this distinction has been all but lost.

 Modern Dance Bands

Setups for Dance Bands.

The section above on Modern Dance Bands contains no mention of the latest Beat Groups, Rock’n’Roll or Skiffle. BBC thinking was clearly lagging at least 5 years behind the latest trends in popular music. If you were a teenager in 1962 the ensembles mentioned above are the sort of music your Mum and Dad would have liked! Within a couple of years British teenagers were under the bedclothes every night with a transistor radio listening to their favourite music coming from pirate radio stations such a Radio Caroline and Radio London, illegally broadcasting from offshore. It wasn’t until 1967 that the BBC threw in the towel and set up Radio 1 to cater for a younger audience!

STEREOPHONY

The final chapter of the manual is devoted to describing the basic principles of ‘STEREOPHONY’. Even though stereophonic records had been around for several years, by 1962 stereo broadcasting was still in it’s infancy. Around this time there were a number of experimental BBC broadcasts. In our house I can remember my Dad following the instructions for a particular broadcast by setting up 2 radio sets tuned to different programmes, one carrying the left-hand channel and one carrying the right !! Unfortunately the 2 radios were very different sizes and so the effect was somewhat less than perfect! It was not until 1973 that Radios 1,2 and 4 finally broadcast in stereo.

In Conclusion.

Although a small amount of space is given to sound in the context of television, this manual is firmly focused on ‘High-Quality Sound Production and Reproduction’ for BBC Radio. Tape had pretty much replaced 78 rpm discs as the primary means of recording and storing programmes. FM broadcasting was a huge technical leap forward and the arrival of some new condenser microphones further improved the quality of the output. Nevertheless, in many respects, even by 1962 ‘Auntie’ still had one foot firmly in the 1930’s !