Category Archives: Microphone Tech Specs

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

Sennheiser MD408N
Sennheiser MD408N

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 Advert 1969 for MD408N
Sennheiser MD408N  Klien Tuchel Connector and standard 3/8 inch stand adapter.
Sennheiser MD408N Klien Tuchel Connector and standard 3/8 inch stand adapter.
Sennheiser MD408N On/Off switch

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.

LABOR W MD7 Omnidirectional Dynamic Microphone Circa 1950.

A Short History Lesson.

In 1945, just a few weeks after the end of World War 2 Fritz Sennheiser and 7 fellow engineers from the University of Hanover set up a business designing and producing a range of electrical equipment in a laboratory called Laboratorium Wennebostel (“LABOR W” for short). The laboratory was named after the village of Wennebostel in the municipality of Wedemark, where it had been relocated during the war. LABOR W began building microphones in 1946 and by 1953 (see catalogue below) they had developed a whole range of microphones, including the legendary MD 21 which is still in production today. By 1955 the company had expanded to 250 employees and in 1958 changed its name to Sennheiser.  

These days microphones from the early LABOR W period are becoming increasingly rare, so when this unusual looking MD7H turned up on eBay, ‘untested’ but very cheap, I immediately clicked ‘Buy Now’.

LABOR W MD7H   front view
LABOR W MD7H  front view 2
LABOR W MD7H rear view
The ‘H’ indicates that this is the High impedance version.

The photograph on eBay however, gave no sense of scale and it wasn’t until the microphone arrived that I realised just how small it is! I was reminded of the anecdote of the person who buys a gorgeous sofa online at a bargain price and when it arrives it turns out to be for a dolls house! Had I seen the LABOR W advert below that might have given me a clue.

LABOR W MD7 Advert early 1950's
‘Our most powerful moving coil microphone
MD7 for speech’

Below are the microphones featured in the 1953 LABOR W Catalogue.

Microphones featured in the 1953 LABOR W Catalogue. Page 1
Microphones featured in the 1953 LABOR W Catalogue. Page 2

(Translation of catalogue description above)

‘MD7 Speech microphone

Particularly good speech intelligibility due to emphasis on high frequencies. Therefore recommended for announcement and dictation systems. The soft rubber housing makes the MD7 insensitive to rough handling. Available in low and high impedance versions.

Dimensions: 76 x 48 x 48mm.’

For a sense of scale here below is the baby MD7 along with its Senneiser cousins the MD21 , MD421 and the mighty MD441.

LABOR W MD7 along with its Senneiser cousins the MD21 , MD421 and the mighty MD441.

Innovative design

In the early 50’s the soft rubber housing of the MD7 was an innovative design feature, and indeed made it very robust and resistant to rough handling. I haven’t tried it, but I think it would probably bounce if dropped from a height! It therefore came as no surprise once I had soldered a jack plug on to the cable it burst into life working perfectly.

So what does it sound like? CLICK HERE

LABOR W production came to an end in 1958 and the name changed to SENNHEISER. The rest is history!

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’!

SM58 cuppingBeyer M58 2 N (C)

 

 

 

 

 

 

 

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 D130

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!

 

Steane’s ‘Ellipsoid’ Ribbon Microphone Circa 1948. A Sorry Tale!

Steane's 'Ellipsoid' Ribbon Microphone circa 1948

Steane’s ‘Ellipsoid’ was a budget ribbon microphone made in Melbourne Australia in the late 1940’s. The advertising literature from December 1948 declares it to be the ‘World’s Smallest Ribbon Mike’!Steanes-1948-advert

Other claims made in the blurb also raised my curiosity, especially the bit about ‘No boom or puff’!  (Never previously on my list of ribbon mic problems!)   So when my newly purchased Steane’s ‘Ellipsoid’ arrived I had to plug it in straight way. However………….. As I turned up the volume on my headphones I was horrified by the sound that assailed my ears. It had a very unpleasant nasal honk and a gratingly harsh high end! This was not what I was expecting! The previous owner had assured me that this shiny gem was fully working and all original. Hmmm!

On opening it up this is what I found. Whaaaaaaaaat TF!

Astatic MC-127

The ribbon motor and transformer had been removed! The body of the mic was filled with grotty, yellowing, wading and a crudely soldered Astatic ceramic element dumped unceremoniously on the top.The whole horrifying confection was sort of held in place with a couple of random bits of grey foam.

Astatic MC-127 back view.

The grill was also stuffed with wading to stop the lose element from rattling around (and maybe improve the tone?) Perhaps it was an attempt to get rid of some of that legendary Aussie ‘Boom’ and ‘Puff’!   Anyhow, I sadly stuffed it all back together as I found it and bunged it back in the post to the previous owner for a full refund. What a disappointment!

P.S.

If like me you are unfamiliar with Steane’s microphones here is their Microphone catalogue circa 1948/9. The mics listed here offer a range of applications for both the professional and the amateur user. I notice that the Dynacard model also guarantees ‘No Boom or Puff’!  🤣  The Home Studio shown on the last page is interesting as it appears to be an early form of Karaoke system allowing the user to sing along with the radio and thereby add ‘zip’ to any party!

Steane's Microphone Catalogue 1948/9 Steane's Microphone Catalogue 1948 P.1 Steane's Microphone Catalogue 1948 P.2 Steane's Microphone Catalogue 1948 P.3 Steane's Microphone Catalogue 1948 P.4 Steane's Microphone Catalogue 1948 P.5 Steane's Microphone Catalogue 1948 P.6

Anyhow, perhaps one day another Steane’s microphone will come my way.

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.                                                                                                    

AKG C451E with old style logo

AKG C451E no serial number

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.

AKG CK1 CapsuleAKG C451E with capsule removed.AKG C451E body with CK1 Capsule

C451E original case interior AKG C451E Original case

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

 

‘The Beatles Mic’ Reslo RB/L Black Label (Circa 1961)

Reslosound Ltd were a British company based in Romford, Essex, manufacturing microphones and electrical equipment throughout the 50’s and 60’s. In recent years the Reslo RB has become known as ‘The Beatles Mic’ because of its association with The Beatles early days at The Cavern Club.

However, as I recall (‘cos I’m that old), the Reslo RB was simply a popular vocal mic with many up-and-coming young beat groups in the clubs and pubs around Liverpool and Manchester. Like the Shure SM58 today, the Reslo RB was not, perhaps, the greatest vocal mic in the world, but it wasn’t bad either, and most importantly it was pitched at a price that gigging musicians could afford! In 1962 the Reslo RB/L could be purchased for £9.12s, which was less than half the price of an AKG D19B. A Sennheiser MD21 cost £16gns, or if you couldn’t quite afford the Reslo you could always settle for a Grampian DP4 L at £8. For their first gig at The Cavern in 1961 The Beatles were paid £5.

So how on earth did a delicate ribbon microphone survive whilst an enthusiastic singer (straining to get heard through a 50watt Vox PA) screamed ‘Twist and Shout’ at a distance of half an inch? (Or in the case of my mate’s band, an old valve amp built into a re-purposed rabbit hutch!) Reslosound clearly knew their market and gave this problem some thought. To avoid instant annihilation of the ribbon, Reslo had a cunning plan! Firstly the RB was designed with the ribbon motor facing backwards i.e. with the ribbon nearest the back of the microphone and thus somewhat shielded by the magnet. Secondly the RBs were supplied with a set of fine fibreglass ‘ acoustic correction pads ‘.

Reslo Filter Pads Kit 1961

These had a range of functions, described in detail in the Reslo Instruction Manual. However, the most important purpose of the pads was to prevent the implosion of breath on the ribbon.

ResloRB_INSTRUCTIONS_TECHDATA

In the almost inevitable event of catastrophic failure Reslo also had ‘Plan B’ in the form of replacement ribbons which came mounted on a plastic frame ready to do a quick swap.  It was also not uncommon for musicians to replace a blown ribbon themselves using the thin aluminium foil that came in cigarette packets! Having heard the results this is not to be recommended……… but it worked!

Rolling Stones 1963

Another bunch of likely lads with a Reslo RB. The Rolling Stones in 1963

The BBC Connection

In 1961 the BBC were looking around for small, unobtrusive microphones to use on TV. After serious deliberation, and thorough testing of the Reslo RBM/T, the Research Department concluded that ‘The performance of the microphone fell short of broadcasting standards’ (a night out at The Cavern would have told them that!).  However, the cheapness and robust construction of the RB was also noted, and they therefore suggested implementing a number of simple changes to the design which would bring it up to broadcasting specification. The full report can be read here…….

 1961 BBC Modifications.

The modified broadcast microphone is known as the Reslo VRM/T

The VRM/T was sold to the BBC for the princely sum of £10 per microphone.BBC TV Grandstand Reslo VRM/T

Home Taping

The Reslo RB was also popular with amateur tape recording enthusiasts. Once again, it gave good results without breaking the bank. The British tape recorder manufacturer Ferrograph sold Reslos with some of their machines and made their own in-line transformers to match them to the input. Here is a review of the RB by Fred Judd, who edited Amateur Tape Recording magazine for a number of years……. ResloRB_review by F Judd

Reslos also appeared in re-badged versions for various equipment manufacturers including VOX and GEC.

Conclusion

Fronting many famous (and not-so-famous) names of the 60’s the Reslo RB has rightly earned a place in rock ’n’ roll history, and thanks to its solid design there are many examples still in circulation. With a bit of a clean and a new ribbon they will probably carry on rocking for another 60 years.

So what does the Reslo RB/L sound like?

CLICK HERE Pete Gill with Reslo RBL

P.S.    If your Reslo RB needs re-ribboning or if you fancy upgrading to BBC spec http://xaudia.com/ do a fantastic job.

 

Sennheiser ”Telemike” (Circa 1976) with ME20, ME40 & ME80 capsules.

Sennheiser ''Telemike'' Operating Instructions. 1976

Sennheiser Telemike with ME80, ME40 and ME20 Capsules

My eBay bargain with K2-U powering module and MZF 802-U 100Hz filter.

Below, page from ‘Telemike’ manual.Sennheiser Telemike Operating Instructions 1976Spezial Teleskop MZS 802

Sennheiser’s ‘Telemike’ is an extremely versatile, high quality, modular, electret microphone system originally designed for reporters and film makers. It consists of a powering module K1, K2 or K3, a metre long telescopic boom arm MZS 802, (how cool is that?) and a choice of 3 interchangeable microphone modules (ME-20 Omni, ME-40 Super-Cardioid or ME-80 Shotgun) There were  also a number of accessories such as the 100Hz filter, windscreens and various clip mounts and table stands.

Unlike all of the other Sennheiser microphones in my collection ‘Telemike’ is extremely light. Even with the ME80 attached to the telescopic boom it adds very little weight to a camera or portable tape machine, making it an attractive tool for location recording. Back in the 70’s an additional benefit of the telescopic boom was that it kept the microphone at a distance from the motor noise of the camera or tape machine.

Apart from professional users ‘Telemike’ also attracted an army of amateur video camera owners and tape recording enthusiasts. It was easy to use and came with a handy booklet of instructions on how to connect Sennheiser mics to a huge range of tape recorders from 51 different manufacturers!! (No that isn’t a typo!) My Dad was a tape enthusiast with an interest in local history, and so when I was a child we always had at least 2 tape recorders in the house! The microphones that were supplied with domestic machines were usually of poor quality. These Sennheiser mics offered the keen amateur a huge improvement in sound quality. They also produced excellent results with more professional machines such as the Revox A77 and B77 which did not provide on board phantom power.

CLICK HERE  for a short voice demo of ”Telemike” featuring all 3 capsules.

Original Users guide and Technical SpecificationsSennheiser MKE 202 User manualsennheiser mke202 manual002sennheiser mke202 manual003sennheiser mke202 manual004sennheiser mke202 manual005sennheiser mke202 manual006sennheiser mke202 manual007sennheiser mke202 manual008sennheiser mke202 manual009sennheiser mke202 manual010

Sennheiser MKE 202. (with K2pre-amp)Sennheiser MKE 202Sennheiser MKE803 (K3 pre-amp with 3 position bass roll-off)Sennheiser MKE803

These versatile modules can also be simply used either hand held or stand mounted. All in all, a very useful set of microphones!

 

 

Wind Shield 4001.A. to fit STC4032 and 4035

In the post yesterday came a small cardboard box  containing a very pleasant surprise. On reading my last post on the STC4032, one of my readers had observed, that I didn’t have the 4001.A. wind shield. These days they are extremely hard to find. He happened to have 2 and so he sent me this as a present! That is very kind and made my day. So, a big thank you to John Machling

Wind Shield 4001.A to fit STC4032 and 4035

And it is in absolutely perfect condition!

The construction of the wind shield is interesting, consisting of a cleverly designed dome of fine wire mesh packed with rubberised hair and other fibres. (Even the thickness and spacing of the wire and hair/fibre is critical! ) An airtight rubber seal easily attaches the wind shield to the mic.

Inside view of STC4001.A. Wind shield

No. It is not a nest for an extremely small bird!

Inside rim of STC4001.A. Wind shield.

To understand exactly how this slightly crazy-looking piece of vintage British technology works it is worth reading the original patent application which explains all. 

Patent Application for STC4001.A.

STC4032 with 4001.A. Wind Shield.STC4032 with 4001.A. Wind ShieldSTC4032 wit 4001.A. Wind Shield

With the wind shield in place, the level of noise caused by winds in the range of 10 – 30 mph  is reduced by up to 16 db, with surprisingly little effect on the frequency response. It also provides a valuable additional layer of waterproofing. It certainly looks like it should be very effective, and as soon as we have some really bad winter weather I will get outside and record a demonstration!