Category Archives: Microphone Tech Specs

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!

 

STC4032-D Outside Broadcast Microphone Ex BBC Circa 1955

STC4032-D

STC4032-D

STC4032C Advert

From the earliest days of outside broadcasting and recording, keeping the microphone dry has always been something of a challenge. Condenser microphones in particular don’t function well in damp conditions, and pretty much any mic can be completely ruined by a good soaking.

These days’ companies such as Rycote make windshields and water resistant protection to cover a wide range of different professional microphones. Back in 1955 STC came up with their own neat and convenient solution to the problem.

Advertised rather grandly as being ‘an all weather instrument’ with ‘full marine and tropical protection,’ the STC4032 is a robust hand-held, omnidirectional, dynamic microphone with a moisture resistant black Bakelite body. The grill is a dual layer of fine stainless steel mesh and an optional windshield (pictured above) may be added to give an additional 15db noise free performance in high winds and additional protection from the rain. The handle incorporates a switch, which can be wired to provide muting or remote start/stop function for a tape recorder (such as the E.M.I Midget).

EMI Midget Tape Recorder

This super lightweight setup was used by BBC outside broadcasters from 1955 until the mid-60’s and weighed a mere 14lbs!  You may laugh…….. But this was a vast improvement on carting round the previous equipment…….. a BBC Type C portable disc recorder weighing 44lbs!!!   (see pic below)   Perfect for recording in a gondola!                                                                                                     BBC OB Disc cutter Venice 1946Michael Reynolds reporting for the BBC in Venice 1946.

Can’t imagine the rocking of the boat helped the disc cutter very much. The mic is an STC4017c and none of this gear is waterproof (apart from Michael’s sturdy military raincoat!)

Legendary sports comentator David Coleman

Legendary sports commentator David Coleman with his trusty STC4032 in hand.

The following is a hilarious period piece, almost like something out of Monty Python:

Alan Whicker interviews Beatniks in Newquay in 1960  (STC4032 appears at 5min 50secs)

https://www.youtube.com/watch?v=W3WfXA9JL9w&t=350s

Actress and opera singer, Rosalina Neri.

This picture of actress and opera singer Rosalina Neri being interviewed for the BBC really deserves a suitable caption!                       ………………………………………………………………………………

STC4032-D

STC4032-D

Although it looks somewhat like a World War 2 battlefield telephone, in terms of technical performance the STC4032 is exactly the same as the STC4035 studio microphone, and very similar to the famous Apple & Biscuit STC4021. It has a notably smooth frequency response from 30Hz to around 10 kHz, with a presence peak of around 5db at 6.5kHz . The only difference with the 4032 is the water resistant case.

Technical Specifications.

STC4032

Here is a short demonstration of the STC4032-D

In Conclusion.

Although ostensibly designed for outside broadcasting, the STC4032 is a high quality dynamic microphone that could be used for many different tasks.

Click Here for a short except from Suite for Soprano Saxophone and Church Organ – ‘In Remembrance’ composed and performed by Patsy Gamble with Jonathan Hope on Sat 11th Aug 2018 in Gloucester Cathedral. Photograph by Duncan Laker.

Click Here for a short clip of Acoustic Guitar. Many thanks to Joe Martin for the brief impromptu solo.

P.S.

For those who are interested in the history of broadcast recording I would thoroughly recommend these 3 sites which are a rich source of fascinating information:-

http://rfwilmut.net/broadcast/recording.html

http://museumofmagneticsoundrecording.org/StoriesBBCEMI.html

http://www.orbem.co.uk/repwar/wr_recorders.htm

Mélodium 76A 1960’s / 70’s

Looking like a cross between a Van Gogh Sunflower and a pepper pot, the Mélodium 76a is a shining gem of chrome and aluminium. A classic of French design!

Melodium 76A Front Grill

In the 1960’s Mélodium developed a variety of modular parts and accessories to give their range of microphones greater versatility and customers more options.

The basic 76A microphone (head) came with a choice of 10 ohms or 200 ohms impedance.

Melodium 76A Head

The mic could be used plugged straight into the cable. (Great for harmonica players!)

If required this handy plug-in transformer converts the 76A from 200 ohms to Hi-Z.

Melodium 76A Transformer

There was also a choice of handles.

Melodium 76A Detachable handle

Melodium 76A with 314 Handle

In this 1970’s Mélodium Catalogue (below) the technical details of the microphones are presented along with a full range of parts and accessories, including goosenecks, tall stands, short stands, table stands and a large selection of adapters, switches and transformers. It is a very comprehensive selection, to cover every possible application.

CLICK Here for MelodiumCatalog

Sadly these days it is hard to find much information about Mélodium. Even in its heyday the company was little known outside of the French speaking world. By the end of the 1970’s Mélodium were no longer in business. Probably wiped out by the superior German and American competition.

Melodium 76A

Finally

Having finished re-soldering all of the joints in my eBay ‘bargain’, I just need to plug it in and find out what it sounds like!

CLICK HERE for Sound clip of Voice and Blackbird in the garden.

The STC4001B Acoustic Baffle for the STC4021 (Apple & Biscuit) circa 1935.

The very first post that I wrote for this blog back in 2012 was about the STC4021 (Apple & Biscuit). Still one of my favourite microphones.  I even made a YouTube video to go with it! In the course of the video I mentioned the STC4001B Acoustic Baffle. According to the STC brochure this could be purchased to modify the frequency response and directionality of the microphone. These days the 4001B Acoustic Baffle is very hard to find. So imagine my surprise when a brand new old stock 4001B (still in the box) appeared on eBay. 

So I thought I had better ‘Buy it now‘ and make another video to celebrate the occasion!

 

AKG C747 More Than Just A Podium Conference Mic.

AKG C747

First introduced in 1987 the AKG C747 was originally designed for ‘unobtrusive speech applications when mounted on a podium or lectern, or for teleconferencing activities’.  From this somewhat uninspiring start, these days the C747 is widely acknowledged as one of the most versatile microphones AKG ever produced!

Just a glance at the tech spec tells you that this was not a microphone simply doomed to deliver the Chairman’s annual report!

  • Smooth frequency response from 30Hz -18kHz.
  • Rapid transient response produced by tiny, low-mass, capsule.
  • Tight hypercardioid polar pattern, giving excellent separation.
  • SPL rating of 133db.
  • AKG C747 Frequency Response GraphAKG C747 Polar Pattern

It didn’t take engineers long to realise that this neat, pencil sized miniature shotgun microphone has many uses away from the conference hall!

AKG C747 Matched Pair

I recently acquired a well-matched pair of old C747s and it occurred to me that although advertised as having some ‘shotgun’ characteristics, these neat little condensers do in fact behave pretty much the same as any other hypercardioid microphone.  I therefore wondered how they would get on as a crossed stereo pair.  I have seen them occasionally used like that in a conference speech setup, but never recording a large symphony orchestra! (Frequently used as spot mics but certainly not as the main pair!)  So here goes …………

CLICK HERE for Symphony Orchestra sound clip.

The mics were crossed at 65 degrees (at the capsules) and positioned on a tall stand about a metre behind the conductor. N.B. To get the full effect of this recording you need to download it in full resolution and play it on speakers at the sort of volume that will really annoy your neighbours!

AKG C747 Crossed pair at 65 degrees

Here below are the Tech specs for both the AKG C747 and the current model the C747 11.  It is interesting to note that in the C747 11 literature various instrumental applications are also illustrated. (guitar, saxophone, snare, drum) The newer model also has a slightly different frequency response, more tailored towards speech. Either way these are fabulous, unobtrusive, little mics that will blend seamlessly into almost any situation!

C747-manual

AKG_C747_Service_Documentation

AKG_C747V11_Manual

AKG_C747V11_Polar_Patterns

AKG_C747V11_Cutsheet

N.B.  The Hi-Pass filter on these mics is hidden away in the XLR plug (also containing the mic preamp) I included this last photo because, in conversation with the previous owner, he told me that he never realised that the 747 had a hi-pass switch!! When working close up he ‘Always found them a bit too bassy ‘ !

AKG C747 Hi-pass filter