Tag Archives: Talking Pictures

American Microphone Company D9A/ D9AT ‘Skyscraper’ (1938- circa 1958)

American D9AT Where's Wally

Where’s Wally/Waldo?

When the American D9A was launched in 1938 it was notable because of its fashionable Art Deco ‘look’ inspired by the skyscraper skyline of New York and other great American cities. Indeed the side elevation of the mic appears to directly reference Manhattan’s famous Chrysler Building constructed in 1930.

American D9 Side View Chrysler Building

This was the age of Jazz, and Rock’n’Roll was just around the corner. Microphones increasingly appeared centre stage in photographs and on screen as part of the performer’s visual image. Over the following couple of decades the American Microphone Company kept ahead of the game producing a number of stunning designs which appeared in movies and featured in commercials.

Katharine Hepburn, Spencer Tracy, Van Johnson, and Angela Lansbury in State of the Union (1948)Katharine Hepburn, Spencer Tracy, Van Johnson, and Angela Lansbury in State of the Union (1948)

The transducer design of the American D9 is also interesting and unusual.

The D9A /D9AT is often incorrectly identified as a ribbon microphone! This matter can simply be resolved by undoing 4 screws!!American D9AT Interior Front viewAmerican D9AT Rear inside viewAmerican D9AT Interior side view

Does this look like a ribbon motor??!!  In the advertising blurb below it is described as being ‘a pressure-velocity combination microphone’ which may have led some folks to think that the ‘velocity’ element must be a ribbon (like the Western Electric/Altec 639). However, the 2 elements are clearly both dynamic. One pressure element (omni) sealed at the back, and one velocity element (Fig of 8) open at the back. The signals from these 2 elements are combined to produce a cardioid directional response. I can’t off hand think of another microphone that is configured in this way using 2 separate dynamic elements.American Microphone Company D9 Advert

Although I can accept most of the description given above, the notion that the DA9 has ‘qualities of ruggedness’ is somewhat farfetched. Sadly, the bodywork appears to be cast in a cheap zinc alloy which is brittle and easily damaged. The yoke is also made of the same material. These days it is hard to find one without bent, cracked or broken ribs.American D9AT Damage to bodywork

Some years ago I was working on a theatre show in which an over-excited actor, (playing the part of Jerry Lee Lewis) unintentionally launched my treasured Electro-Voice EV664 right across the stage. It landed 30 feet away with a sickening thud. Apart from a slightly damaged switch the mic was unmarked and still worked perfectly! That is rugged! I wouldn’t want to try that with my D9AT. This is definitely not a mic to drop by accident. As well as the fragile body the chrome plating is remarkably thin. Even though my D9AT is from the tail end of production in the mid 50’s much of the chrome has worn away. Nevertheless it is still a stylish looking object.American Microphone Company D9AT

BUT………….. More importantly what does it sound like?  CLICK HERE for Voice Recording

The American Microphone Company D9A / D9AT was not designed as a high quality studio instrument. It was recommended for P.A. and installation use. In 1938 most dynamic P.A. mics were feedback-prone omnis. American’s dual element cardioid with its promise of higher gain before feedback could therefore be seen as an exciting new development. However, the following year Shure launched their game changing Unidyne 55 featuring a single cardioid capsule. The new single capsule design was soon adopted by most manufacturers as it was clearly cheaper to make and capable of producing excellent results. American carried on manufacturing the D9A/ D9AT for another 15-20 years. In 1955 the company was bought by Elgin-Neomatic,Inc. whose main business was watch making. At the time Elgin had the notion that they would develop miniature parts for microphones but this idea soon faded. My D9AT featured here is from the Elgin period.Badge ELGIN American Microphone Company D9AT

Around 1960 American was sold again to General Cement Company Rockford, Il (AKA G.C.Electronics). Several years later the company was finally bought by Electro-Voice who soon retired the brand.

In Conclusion

Although the American Microphone Company D9A/AT may not win any prizes for its audio quality it nevertheless provides an interesting link in the development of directional microphones in the first half of the 20th century.

Electro-Voice DO56L Dynamic Shock Mount Omni circa 1980

Perfect for the socially distanced interview!Electro Voice DO56LElectro Voice DO56L OmniElectro Voice DO56L with original case

Following in the company’s long tradition the Electro-Voice DO56L is a triumph of innovative design and precision engineering. The 11 and a half inch 56L is the Long version of the DO56 and was intended as the perfect tool for TV news gathering or Talk Show Hosts. Even the dull ‘Silver tone beige’ finish was carefully chosen to be unobtrusive and none-reflective under TV lighting.

Electro-Voice advertising material from 1980 featured below explains in detail the design of this exceptional new microphone. The clever arrangement of the internal shock mounting is particularly impressive.

Electro Voice DO56L Literature. page1Electro Voice DO56L Literature. page2Electro Voice DO56L Literature. page 3

Phil Donahue Edit

Can’t beat a bit of subtle product placement/celebrity endorsement!

So What Does it Sound Like?  CLICK HERE for spoken word clip.

What else can it be used for?

Back in the 1950’s when AKG came up with the D12 they fondly imagined that they had designed a general purpose instrument and vocal mic. The marketing blurb featured photos of pretty girls warbling sweetly into the new microphone and indeed it was a great success with singers. Then along came the studio engineers who took a look at the tech spec and said, ‘Hey…. I bet with that frequency response curve and high SPL rating the D12 would sound great on bass drum’!  Within a few years it was on bass drums all over the world! In fact these days it is often referred to as the ‘legendary bass drum mic’ (no mention of vocals). So when I see marketing literature declaring a microphone to have a particular purpose I always find myself imagining (based on the tech spec) what else it might be good for.

Although the Electro-Voice DO56L was very much designed with demands of TV journalism in mind and a frequency response tailored to the human voice, I feel sure that it could also have a range of other uses. So let me see now……………

More Sound Clips to follow as soon as COVID-19 allows!

 

Martin Mitchell’s Music For 3 Saucepan Lids and Spatula ! Recorded by the Gaumont-Kalee Type 492. 😊

Inspired by washing up! I did this recording for a bit of amusement on a cold rainy Saturday morning (crazy sound engineer’s idea of having fun!) ……… but I really love the way this beautiful old ribbon mic reproduces the ring and detail of these sounds. I suspect that the 492 would also make a great drum overhead. Anyhow, enjoy!

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

Gaumont-Kalee Type 492 Side viewGaumont-Kalee Type 492 Side view2Gaumont-Kalee Type 492Gaumont-Kalee Type 492 Box

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.Gaumont-Kalee Portable Recording Equipment

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.Gaumont-Kalee Type 492 inside 1Gaumont-Kalee Type 492 inside 2
  • 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.Gaumont-Kalee Type 492 inside 3Gaumont-Kalee Type 492 inside 4
  • 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!

GB-Kalee 1950 Catalogue. Cover

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 !)

 


Gaumont-Kalee Catalogue Page 4

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.

Electro-Voice EV642, 643, & 644 Cardiline Microphones , (circa)1960

Ever since the advent of the ‘Talkies’ sound technicians have struggled to pick up speech in motion pictures with sufficient clarity. For many years the problem of getting the microphone close enough to the performers without it being in the camera shot was a constant challenge!  On the other hand if the mic was too far away the sound was often ruined by the pickup of unwanted surrounding noise.

Seeking to address this problem, in October 1959 Wayne A. Beaverson of Electro-Voice filed for a patent on a new type of directional microphone which could be successfully operated at a distance from the sound source.  At low frequencies this microphone exhibits the directional characteristics of a cardioid mic, with excellent rear rejection. As the frequency response rises it becomes a line mic with considerable attenuation of unwanted sound from the sides. Thus the new ‘Cardiline’ design provides excellent directivity right across its operating frequency range.

Electro-Voice Patent for Unidirectional Microphone 1963

The success of the new microphone was such that in 1963 Electro-Voice received an Academy Awards “Oscar” for the development of the model 642 Cardiline, The award, in part, read “To Electro-Voice for a highly directional dynamic line microphone… capable of picking up sound in situations where a microphone cannot be placed close to the sound source and where unwanted sounds are to be discriminated against.”

Although the Academy Award went to the 642, the microphone drawn and described in the original patent application was in fact its close cousin the EV644. At this point you might be wondering about the 643?  Well ……… The 643 was pretty much the same as the 642 except in one significant detail ……… it was just over 7 feet long!  All three of these mics were of the Cardiline pattern but they were aimed (excuse the pun) at different areas of the market. As we know, the 642 was tailored very much for the film and TV industry and came with an elastic mount for attaching to a boom.

EV642 Advert 1963

EV643  Advert

Electro-Voice_643 Advert

electrovoice_643_2

Although extravagant claims are made for the mighty 643 in the advert above, I suspect that this mic was in fact quite awkward and unwieldy to use (even sighting along the barrel!!) It is certainly hard to find any fond recollections of it. I came across one report from some poor sod who once spent an afternoon standing on the roof of a football stadium trying to follow the ball round the field!! Anyone who has ever operated a theatre follow spot will appreciate just how ludicrous that must have been!

Which leaves the 644. (My latest eBay bargain!)

electro-voice-ev644

Designed for use on stage, in theatres, auditoriums and churches,  the EV644 Sound Spot came with a microphone stand mounting and was finished in classic Electro-Voice chrome. You could also buy it with a dull matt paint finish,(non-reflective under lighting), but why do that when the chrome version just looks so rock’n’roll cool !

Allied Catalogue 1960

List Price $110. A bargain at $64.68 ! (Not cheap in 1960!)

ev644-back-end ev644-body-and-stand-mountev644-end-grillev644-original-box-insideev644-original-box

CLICK HERE for Voice recording at a distance of 12ft

CLICK HERE for Glockenspiel Recording

In Conclusion

The 1963 patent shown above acknowledges a number of earlier inventions relating to directional microphones. In particular the patents of Harry Olson dating back to 1939. However, the earlier inventions, (mostly involving complex arrangements of multiple tubes of differing lengths), were awkward and cumbersome. In contrast, Beaverson’s Cardiline microphone, using a single multi-path tube feeding a single cardioid capsule, was an uncomplicated work of genius. It was both effective and easy to use.

To this day the elements of Beaverson’s patent can to be seen in shotgun microphones all over the world.

Below are the Techincal Specification Sheets for all 3 microphones.

Electro-Voice 642 Spec Sheet

Electro-Voice 643 Tech Spec.

Electro-Voice 644 Tech Spec

A Rare Siemens (?)/ Telefunken (?)/ Klangfilm (?) Ribbon Microphone. (circa 1931)

The Facts

  1. It is a cardioid ribbon microphone.
  2.  Weighs over 10lbs.
  3. The microphone was aquired many years ago in America by the previous owner, the film editor David Hawkins (known for his work on the films of Jean Renoir and also The Collector.)
  4. It carries no manufacturer’s identification marks……….. however
  5. The lower half of the microphone is identical to the Siemens SM3, (aka Telefunken  ELA M25b and ELA M201/1 and as Klangfilm ELM24) as specified in Siemens (UK Reg) Ribbon Patent 1931
  6. On the front there is a simple brass plate declaring it to be a ‘Microphone Type R’ and a ‘Serial No 1028’

An Interesting Comparison

1930’s Siemens SM3 technical illustration

Same view of lower half of my Siemens (?) Appears to be identical, even down to the painted letter N indicating the polarity of the magnet.

My Theory

In the history of microphone technology Harry Olson of RCA is often credited with having invented the ribbon microphone and developed the first directional microphone. However, whilst it is important to recognise Olson’s major contributions to microphone technology, the accolade for inventing the ribbon microphone clearly belongs to Erwin Gerlagh and Walter H  Schottky, working for the German company Siemens in the mid1920’s. It was also the case that the early Siemens models such as the SM3 were well known for their directional properties. The back of the ribbon is enclosed by a huge ring magnet, and an ingenious arrangement of acoustic chambers,  thereby producing a cardioid polar pattern. Although the lower half of my huge microphone, including the magnet and ribbon assembly, is identical to the standard SM3, the upper half appears to be an additional acoustic chamber of some sort, packed with wadding (perhaps to provide additional damping to the ribbon and influence the HF reproduction?)

In the early days of Talking Pictures in America the microphones available were omnidirectional and thus it was difficult to balance the level of one actor’s voice against another especially if the one was more powerful than the other. Omnis also tended to pick up camera noise and anything else in the way of unwanted sounds on the set, considerably degrading the quality of the finished product.

Technical competition within the industry was fierce and American film studios of the period had strong commercial ties with the major players in the development of cinematic technology such as Western Electric and RCA.  In Europe competition came from the Tobis-Klangfilm cartel, and Siemens was pumping large sums of money, and expertise, into developing the technical prowess of its Klangfilm system.

However, there is a small body of evidence that would suggest that a number of American studios, realising the advantages of a directional microphone, bought in the Siemens microphone. It is well documented that MGM used one on the voice of Jeanette MacDonald in their 1935 film of the operetta ‘Naughty Marietta’. It is interesting to note that Douglas Shearer (head of MGM’s technical department) won an Oscar for the sound on that film! The Siemens mic was subsequently used on several other films featuring Jeanette McDonald and Nelson Eddy in order to even up the level difference between their voices ( Eddy being much more powerful.)

My suspicion is that the use of the Siemens microphone in American studios before the arrival of Olson’s superior RCA models was perhaps more wide spread than has been previously admitted! Could this be a possible reason why this Siemens(?) mic in my collection bares no German markings…… could it be that they have been carefully removed for reasons of commercial sensitivity? …… and is the plate on the front in English simply an attempt to make it appear to be of American origin?

As the decade progressed the Siemens was largely superseded by the, lighter and more sophisticated RCA models developed by Harry Olson. Also the dual element Western Electric 639-A.

Meanwhile………

In Germany the Siemens microphone was popular throughout the 1930’s appearing regularly on stage and on screen with that rising star of news reel cinema, Adolf Hitler! During the 1930’s Siemens formed close ties with the Nazi party and helped substantially to finance Hitler’s war machine. During WWII Siemens went on to employ thousands of slave labourers in their factories……….. All of which makes me wonder……  Could it also be a possibility that uncomfortable associations with Germany and Nazism lead to the de-badging of my Siemens microphone?

Conclusion

I think that there is no doubt that the lower half of this microphone, including the huge magnet, cased in shiny black leather, and the ribbon motor assembly were manufactured by Siemens. Whether the upper chamber was a later modification by a third party or whether the whole thing is a very rare model or even a prototype we may never know. Seimens own records for this period are somewhat incomplete and I have found no documentation or pictures (anywhere) relating to this exact model.

If anyone reading this has any more information or other theories relating to this post I would be very interested to hear from you. Meanwhile here are a few more pics of this extraordinary piece of hardware.

Wadding in top chamber.

Empty top chamber. Screws on inside left indicate possible position of missing transformer.

Ribbon assembly removed, awaiting a new ribbon.

Ribbon, cut, crimped and ready to tension

Ribbon in place ready to slot into gap.

Siemens SM3 Magnet gap into which ribbon assembly slots.

Upside down. (though I think it is designed to work either way up.)

Finished at last!! Fully restored and working…… so pleased!!

So what does it sound like?  Here is my first test recording on acoustic guitar.  (many thanks to Den and Adrian for a fun afternoon experimenting!)

Guitarist Den Parratt with the author setting up the mic for our first recording!

Following in the footsteps of mad dictators and MGM film stars of the 1930s here is a vocal clip from talented young singer Joe Martin.

Here also is a fabulous album of gypsy jazz recorded by Echoes of France on this extraordinary microphone. https://echoesoffrance.bandcamp.com/

Joe Stalin. Another satisfied customer!