In part 3 of this series we looked at the first practical dynamic microphone…the model 618 by Western Electric which came out in the early 30s. Bell Telephone Labs engineers didn’t rest after obtaining success with their first dynamic…by 1935 they had developed a real leap ahead in microphone design. The new mike was a big improvement over the model 618. This new mike was dubbed the model 630…but everybody called it the “eight-ball”…one look at it and you’ll know why.
Tests made by engineers at Bell Labs on the effects of various shaped objects on sound waves produced conclusive data which resulted in the selection of the spherical-shaped housing as the best suited in reducing directional distortion. The Eight-ball was the first truly non-directional dynamic and was designed to be mounted facing upwards. On top of the sphere were the sound entrance holes and over the top was an acoustic screen, two and a half inches in diameter and surrounded by a protective metal ring. This screen had wire mesh on either side of several layers of treated silk cloth. This screen reflected the sound waves coming from below and above in such a way as to make the pickup very uniform from any direction.
Because of the look of the mike with the flat screen on top of the round body…the British called their version of the Eight-ball…the “Apple and Biscuit”! The British telephone company, Standard Telephone and Cable (STC), had the license from Western Electric to manufacture this mike in England… and I believe it was used by the BBC right up until fairly recent times. This British version had the STC model number of 4021.
The overall quality of the model 630 was much better than the earlier model 618. Response to low and higher frequencies of sound was much smoother. The size of the 630 was much smaller as well and I think it was just a much cooler looking mike than the rather ugly 618. This mike had a special three conductor plug that fit into the bottom of the mike which also incorporated the stand mounting threads. There was also an accessory chrome swivel-joint that could be used to tilt the mike.
The Eight-ball dynamic found it’s way into big and small radio stations all over the country as well as finding uses in motion picture and recording studios. WOR in New York, a big 50,000 watt station, was a big user of the Eight-ball when it first came out. The Oakland Tribune station, KLX, used the model 630 on it’s live morning show back in the 40s and early 50s. I have a big band record album that features the Benny Goodman band with a picture of Benny and the boys in concert in the 1930s with an Eight-ball on a floor stand right in front of the band. I’ve also seen a film of Peggy Lee singing with Benny’s band and using the Model 630 Eight-ball.
Next time we’ll look at the very last dynamic mike designed by Western Electric which became even more popular than the Eight-ball.
Microphones have been around since Alexander Graham Bell invented the telephone. In radio, television and recording, the microphone is the the very first instrument used in the process of picking up sound. So the “mike” is pretty important and went through development from relatively primitive devices in the early days to units that could very faithfully reproduce the full range of humanly audible sound.
In this segment I want to concentrate on those broadcast-type microphones that had a huge impact on the industry from the early 1930s through the 1960s.
Here is one of the most recognizable broadcast and recording microphones made in the USA. The RCA model 44 series. These were first developed back in the 1930s by Harry Olson of RCA Labs in Camden New Jersey.
The first in this series was the 44A. The model 44 microphones were called “ribbon-velocity” microphones because the internal workings were comprised of a thin corrugated aluminum element, called a “ribbon” suspended in a strong permanent magnet field. This ribbon was the generating element taking sound waves and generating a tiny electrical current that was an exact representation of the sound. This small signal was stepped up by a transformer so it could be sent down the cable to the equipment it was connected to.
The basic ribbon-velocity microphone has a bi-directional pickup pattern. That means that it picks up sound equally well from the front and back of the mike but is relatively dead to sound arriving from either side. This pick up pattern was very useful in the so called “golden age” of radio…especially in dramatic programs where several actors could be grouped around the mike. There could be two or three actors facing the front side and another group facing the back side of the ribbon mike and all would be picked up equally well.
If the script called for someone to walk into a scene the actor would move from one of the dead sides of the mike to a live side providing a perfect “fade-in” The same could be done in reverse for a “fade-out”.
Radio announcers always loved ribbon mikes because they tended to make the voice sound more “bassy” or deep sounding when worked closeup. One of the problems with this is that the ribbon element was very fragile and could be easily stretched by a blast of breath from a close-talking announcer. This also caused a big “pop” in the audio. RCA recommended a working distance of a foot or more for ribbon mikes….of course this was predicated on having a well designed studio with proper acoustics!
The RCA 44 series of microphones were manufactured from the early 30s to 1958. They went through several updates ending with the 44BX.
The RCA 44s were used by all the major radio and TV networks, local radio and TV stations, as well as recording studios. They were excellent for music pickup as well as voice. The 44 is a heavy weight in more ways than one….it weighed in at 8 pounds!! Obviously the 44 was not intended as a hand mike! Also it could not be used outdoors where wind was a factor and the big warning for any user of a ribbon mike was….”don’t ever blow into it”!
These mikes are still in demand and have seen a resurgence in recent years with digital recording. Although RCA stopped making microphones about 1973, there are ribbon mikes being manufactured new today by many makers here in the US as well as China and Russia. The ribbon mike has a very smooth, mellow sound that is very pleasing to the ear.
You can find old RCA 44 ribbon mikes selling on Ebay for up to several thousand dollars. This is a testament to the enduring quality of these units even after over 50 years since they stopped being manufactured. The amazing thing is you could have bought a brand new 44BX in 1957 for $129…of course, that’s in 1957 dollars!!
There is a company in Pasadena, Audio Engineering Associates, that makes an exact replica of the RCA 44 called the AEA 44…..They sell for around $4,000. Some of the biggest recording studios are using these modern replicas in music productions of all kinds today.
So that’s the brief story of the RCA model 44. For more info on this and many other microphones, I recommend Stan Coutant’s website www.coutant.org. Stan has pictures and specs and also audio sound bites to give you an idea of how various mikes sound.
In future posts I’ll review other great broadcast mikes like the RCA 77 and the Western Electric/Altec 639 “birdcage” and several more.
Last time we featured the RCA 44 series of high fidelity ribbon microphones which were the “top of the line” in their day. Radio Corporation of America was in the business of making money…so the audio division decided to design a less expensive version of their very successful model 44 that would appeal to a wider segment of the audio industry.
Somewhere around the middle 1930s RCA came out with the model 74 ribbon mike (microphone) …it was nicknamed the “Junior Velocity” Velocity is another term used to describe a ribbon microphone. This refers to the way in which a ribbon mike picks up sound…by the velocity or speed of air particles pushed by sound waves toward the mike.
The Jr. Velocity was a junior in size compared to it’s big brother. It was about half the size as well as being much lighter weight. The model 74 did not have quite the extended frequency response…or fidelity of the model 44 series….but it still was a very good sounding mike. It also did not have the rubber shock absorber or forked mounting of the 44. It had a unique ball and socket type stand mounting that allowed the mike to be tilted up or down toward the sound being picked up.
RCA’s Model 74B came out somewhere in the late 30s and was very popular. It was manufactured until, I believe, about 1950. The first 74B’s had a shiny chrome windscreen with a black bottom and then in the 1940s RCA changed the wind screen to a brushed chrome and the color of the bottom part to what they called “umber gray”. Umber gray looked more like brown to most people! The change in color scheme was necessary for television as they didn’t want shiny parts becoming a “glint” in the camera’s eye.
The model 74B cost less than half of it’s big brother the model 44. This mike was very popular with smaller radio stations, but even many larger stations used them especially for announcing and for indoor remote broadcasts because of their small size and light weight. The 74 was very much used on PA systems, too, due to it’s lower cost. Even though the quality of sound did not quite match the model 44…the Junior ribbon still had the smooth, clean sound typical of a ribbon mike.
Radio stations in the local area that used the RCA Junior Velocity included KBEE, KFIV, Modesto Jr. College radio and KYOS. The McClatchy stations like KFBK, Sacramento and KMJ, Fresno also used the 74B.
Around 1950 RCA replaced the 74B with the KB2 “Bantam Velocity”. This mike was much smaller than any previous ribbon mike. The Bantam used much stronger magnet material that came out of WWII…this allowed the smaller size. The actual case of the mike was part of the pole piece of the ribbon magnet. Another name for the KB2 was “paint brush” because it had a built-in handle that made it look very much like a small paint brush. Inside the handle, under a cover piece, was an “XL” type connector. The “XL” connector was made by Cannon Electric Co. of Los Angeles which would later bring out the “XLR” connector that everyone knows today. RCA claimed that they commissioned Cannon to make the “XL” connector especially for the KB2 series of mikes.
In about 1954 RCA replaced the KB2 with the SK-46…this also was a relatively small size ribbon microphone that RCA continued to manufacture until they stopped making mikes. For more information on these mikes go to “www.coutant.org”,
RCA brought out one more bi-directional ribbon mike before they went out of the broadcast audio business. Actually this mike, the BK-11, was to replace the 44BX. It is about the same size as the Junior Velocity but with a more curved, modernistic shape, it also has a swivel mounting on the bottom. The BK-11 is an excellent quality mike like the 44BX. This mike is still seen once in a while on Ebay but I don’t think RCA sold as many of the BK-11 as compared to the model 44s and 74bs…which are seen all the time on Ebay. Until next time…this is Mr. Microphone signing off for now!
Our previous sessions have dealt with ribbon microphones by RCA, one of the two prime makers of broadcast and sound equipment in the mid 20th century. This time we’ll turn to the other of these major makers, Western Electric Company.
RCA and Western Electric were fierce competitors in this era. I think I am safe in saying that the majority of radio stations from the 1920s through around 1950 used either RCA or Western Electric equipment, or a combination of both. Western Electric was the manufacturing arm of Bell Telephone…but also made broadcast equipment designed by Bell Telephone Labs. In 1949 Federal anti-trust laws forced Western Electric to divest of their broadcasting equipment manufacturing. Both these companies made just about everything needed to equip a station from microphones and audio control to transmitters and antennas.
About the time RCA came out with the revolutionary ribbon microphone…Western Electric developed the first high-quality dynamic microphone. The dynamic uses the same basic principle as the ribbon….a moving conductor in a magnetic field to generate the audio signal from sound waves. Instead of a moving foil ribbon…the dynamic uses a round-shaped diaphragm that has a coil of wire attached that moves in the magnetic field…it’s a small electric generator. Another way of explaining a dynamic microphone is to think of it as a loudspeaker in reverse! A loudspeaker takes a signal from a radio receiver or amplifier and turns that electric signal into sound we can hear. A microphone, as we explained before, takes that sound we hear and translates it into an electrical signal so it can be amplified and sent to a loudspeaker, as in a PA system, or for broadcasting or recording.
Western Electrics’ new dynamic microphone was dubbed the model 618 and came out about 1931. The model 618 was an omni-directional…or non-directional mike that was relatively small in size and very rugged…making it excellent for studio as well as remote broadcasting, especially in the outdoors. This mike was not sensitive to wind and breath noises like the ribbon mike…and it was relatively insensitive to handling noises making it excellent as a hand mike for interviews and such.
The model 618 was a great improvement over the earlier noisy carbon and bulky condenser mikes of that era. The 618 was a big hit with the radio industry and these mikes were used clear into the 50s. RCA, of course, would not be left behind by Western Electric….so they shortly came out with a very similar-looking mike they called the model 50A. Internally the RCA model 50A used a slightly different way of imbedding the wire into the diaphragm so as not to infringe on Western Electrics’ patents….but externally they looked very similar.
You’ll see both of these mikes in news photos and newsreels of the day…they were used for President FDR’s “Fireside Chat” broadcasts. If you look closely at these photos you’ll see that CBS and Mutual (MBS) used the Western Electric and NBC and the Blue networks used the RCA because NBC was owned by RCA.
A few smaller manufacturers also made mikes that looked very much like the Western Electric and RCA units but these smaller outfits could not compete with the two giants in the broadcast industry and their mikes were used mainly in PA systems and some smaller radio stations.
The dynamic-type microphone is one of the most used units up to this very day…and Western Electric was the start of it all. These pioneering mikes were all omni-directional….picking up sounds from all around…later a small company, at the time, named Shure Brothers designed the first uni-directional dynamic mike called the “Unidyne”. Most dynamic mikes today are uni-directional picking up sound from the front side of the microphone and rejecting sounds from the rear, thus preventing sound system feedback (howling) and eliminating background noises, and all based on Shure’s ground-breaking development of the late 1930s.
We’ll save that story for another session.
Spec sheet for the WE 618 4
By -Derek Waring
The Modesto Radio Museum has lost a very dear friend. Mel Freedman passed away January 11, 2017. Uncle Mel, as he liked us to call him, was the engineer when I worked at KFIV. He was known for his cantankerousness which masked a loving and caring soul that subsequently became so evident. We remained friends over the years. I will miss our lunches and our drinks together Uncle Mel. I was privileged to have you as a mentor and such a big part of my life for so many years. Mel was a Board Member and the Secretary for the Modesto Radio Museum since its inception. He also belonged to the Central Valley Broadcasters (CVB). On behalf of the Modesto Radio Museum and the CVB our condolences go out to Mel’s friends and family. We share in your sadness.
– Derek Waring-
Modesto Radio Museum Board Member
June 15th 2017
Mel’s family has shared with us that he had suffered a serious stroke in early January of 2017, and passed away on January 11, 2017. Mel requested a simple burial and since he was a veteran of World War II, was laid to rest at the National Cemetery at Santa Nella, California. He requested no Memorial service or notice in the paper.
April 3, 1969
William H. (Bill) Bates, Jr. died Thursday April 3 , 1969 of an apparent heart attack while at his daughter’s home in San Jose. He was 68 years old and had been ill and off work for the past three weeks. The apparent fatal heart attack occurred shortly afternoon at the home of his daughter, Delores Williams in San Jose where he had been staying following his release from a hospital where he had been several weeks. He was a native of Freedom, CA (Santa Cruz County).
Mr. Bates entered Oakland Technical High School in 1919 where he studied for his commercial broadcasting license he obtained a year later. He became interested in Amateur (Ham) radio and a year later earned one of the first Amateur radio licenses issued in the country. The call sign was 6KL, which, in later years was changed by the FCC (Federal Communication Commission ) to W6CF . He belonged to the Century Wireless Association as well as the National Association of Broadcasters (NAB).
Mr. Bates worked for RCA corporation and as a radio technician for the Mexican Navy in the early 1920s. From 1925 to 1928 he owned and operated a radio repair business in the Covell building in downtown Modesto before building KTRB in 1933.
Mr. Bates, and his partner, Thomas R. McTammany, put Modesto’s first commercial broadcast station KTRB on the air on June 18, 1933 operating from studios at the corner of McHenry Ave and Sylvan Rd. in Modesto. A location, at the time, that was nearly 3 miles out in the country from the then city limits of Modesto. In 1941 Mr. Bates purchased 40 acres of wheat land on Norwegian Ave. in Modesto and built a new facility. In 1949 he added an FM station, KTRB-FM, to his business.
Mr. Bates had been heard on the station for more than 30 years with his “Old Time Tunes Program” from 8:15 to 10:30 Monday through Saturday mornings.
He was active in the Elks lodge and the originator of the Fourth of July parade in Modesto. Through the years he remained as the general chairman of the event.
Bates is survived by his widow, Maxine Bates; two daughters, Delores Williams and Carmelita Lockbaum, both of San Jose, and six grandchildren. Final rights were held at the Franklin and Downs Funeral home April 7, 1969 with the Rev. Donald G. Weston of St. Johns Chapel of the Valley officiating. Interment was at Lakewood Memorial Park in Hughson.