Part three:  Sound Gear - Microphones
There's a definite holy trinity of location microphones for television crews.
The Shure SM89 and the MKH416 and MKH60 from Sennheiser, all of which
cost well over a thousand quid. Not only do they reproduce stunningly clear sound
but are incredibly robust and shrug off dampness and changes in temperature and humidity.
Microphones tend to be designed for a specific task, which means that most videographers end
up with a general purpose microphone or a huge dent in the bank balance. To fill this gap in the
market Sennheiser came us with the K6 modular system which has now become the videographers
firm favourite. The idea is simple. Microphones basically consist of  two parts, the top half which has the
diaphram and a housing which varies depending on the purpose and requirements, and the bottom half with
the electronics which are, more or less, the same for each microphone. Sennheiser has physically split the two
such that you have one K6 module and then screw on the appropriate top half, depending on what you want to record.
The K6 base module is powered by an AA battery or 48v phantom from the camcorder or mixer. This ability to run off
cheap and readily available batteries is what makes it so attractive to prosumers since not all camcorders can deliver phantom
power and some other manufacturers insist on powering their mics with specialist, difficult to find, and expensive, batteries.
The MKH60 from Sennheiser has
become the "standard" microphone for
most television applications. It is
expensive though, costing over £1,000
(€1600) but it records sound with an
incredible accuracy. Sennheiser was
originally formed to manufacture
measuring instruments and their
microphones are known for (almost
painfully) accurate reproduction of
sound. This accuracy can be so sharp
that singers and performers will often
chose a microphone which is "kinder"
to their voice.
The Sennheiser K6 System
The K6 system works on a
simple idea. The electronics of the
microphone are in a module which also holds a
battery (if required) and supplies the business end of the mic with
power. The top end of the unit is interchangeable and the user
simply screws on the tip with the required characteristics. If you're
only ever going to use one microphone for every purpose then
this isn't the right system for you but if you need microphones with
differring polar patterns then the K6 system will probably work out
better value for money than buying a number of separate
individual microphones. There is quite a range of patterns and
characteristics available for the K6 system ranging from an
omni-directional M62 to the long, thin and very directional M67.
Their only negative point is that, being electret microphones they
can give the occasional crackle in steamy or humid conditions.
So if you're filming in the jungle, you might want to
triple your spending and splash out on a
RF condenser microphone. For
weddings  in Yorkshire,
the K6 system will
cope admirably.
The M66 is the most common "top bit" used on the K6 and this K6/M66 combination is
used by news teams, wedding and industrial videographers all over the world. The M66
is what's called a hyper-cardiod microphone which means that it is quite directional in its
response with good rejection of unwanted noises from the sides. This combi is
sometimes called "the poor man's 416" by sound recordists which is a bit condescending
since it can produce excellent results and will certainly out perform any on-camera, or
sub-£400 microphone.
When it comes to recording conversation, a directional microphone like the M66 can be
a bit limiting unless the subject is placed firmly in the mic's "footprint". This isn't a
problem if the mic's on the end of a boom or "fishpole" and there's someone pointing it
at the subject, but for voice-overs where the talker might move or situations
like wedding speeches where one microphone has to record a
number of different people, a slightly wider angle of
"sound capture" is required. So, unscrew the
M66 and use a cardiod microphone
like the M64 and you've
solved the problem.
Sound Bites:
Previous Page                        Next Page                          Magazine Index                    VideoForums.co.uk   
Magazine

Next Page

Previous Page
The Sennheiser K3 System
The Sennheiser K6 modular system was developed out of the
predecessor, the K3 (Don't ask me what happened to K4 and
K5) which also worked with an interchangeable head. The K3
was discontinued in the 1980s but secondhand examples
continually surface on Ebay and other sites. The main
disadvantage with the K3 was that the amplifier needs a small
battery to operate. This battery is very eco-unfriendly and
subsequent regulations mean that it isn't manufactured
anymore although you can still find them in some photo
shops. The K3 can work on 48v phantom power but only if
there is a battery in the compartment.
So, what at first seems a bargain can end up being an
expensive paperweight. Be careful when buying secondhand
capsules for the K6 module as both systems start with the
letters "ME" followed by a number. For example the ME 64
and ME66 are K6 heads but the ME60 and ME80 will only
work with K3 modules. A lot of sellers "forget" to point this out.
The K6 system: Tops and tails
The ME62 is an omnidirectional microphone which means
that it picks up sound from all directions. This is
advantageous when recording
room "ambience" and the ME62
is the best head in the K6 range when it comes to rejecting
rumble and handling noises.
The ME64 is a cardiod microphone head. This is the most common
pattern for recording music. It is also a nice pattern for recording
speech and is often used as a "poor man's voiceover" microphone.
This is the polar pattern of
the ME64. In essence it
shows what the microphone
will pick-up at different
frequencies and distances.
The left side of the diagram
shows the lower frequencies
which are heart shaped
(hence cardiod) Each ring
represents a 5db change in
volume so we can see that
the microphone only picks
up half the sound at right
angles compared to the front.
The important frequencies
for most recording situations
are from 500 to 8000 Hz.
The K6 comes with a range of heads, five at present, each
of which has a specific pick-up pattern and intended use.
Sennheiser has designed a vocal microphone for the K6
system, the
ME65 is particularly suited for speech and
recording vocals. This means that it's realtive insensitive
                                    at the lower frequencies and its
                                    sensitivity at the very high notes
                                    drops off quite dramatically.
It has a hight maximum sound pressure level (SPL) which
means that it copes well with loud noises.
The most popular microphone for videographers is the "lobar" pattern, sometimes called a
shotgun or short-gun directional microphone. The
ME66 is the K6 version of this microphone.
Looking at the polar patter of
the ME66 you can see that it
rejects sounds from the sides
and rear but remains sensitive
to frontal noises. This is
particularly useful in situations
where ambient noise could
cause problems. It does mean
however, that the microphone
must be "aimed" at the subject.
If your source is even slightly
"off axis" the resulting recording
can sound distorted and "thin".
It has a poor low frequency
response to reduce handling
noise and thrumble.
The ME67 is a specialised, highly directional microphone   
              head meant for recording situations where it's not
                                possible or practical to get in close      
                                           with a microphone.