Microphones.......

Say you are in a rush, you have had this interview with Miss Dion scheduled in your diary for months but you boss is being a drag and now you have to navigate your way through the London Underground system. So you gather your things, grab the Edirol and hurl the first microphone you see into your trendy over-the-shoulder satchel. Its good, you are going to make it. Walking in to the room you find Celine (she asks you to call her that). She has had several coffees and is upbeat and answering your questions better than you could have hoped, she even talks candidly about receiving the Legion of Honor and then thanks Napoleon.
Your boss is going to love you, this interview will surely hit the big time, the prime time, this is YOUR time. As you sit down to edit the piece it dawns on you. This is why you have had the sinking feeling that missing the lecture on microphones was a bad idea. The sound is all muffled, you can only hear your questions and in places there is no sound.....silence? But there wasn't any.

Let me explain. Knowing your microphones and their different uses, strengths and weaknesses is very important. There is so much more to it than this but here is a brief overview of what you will have to know:


DYNAMIC MICROPHONES:
- Fairly rugged and hard wearing microphones
- Much more resistant to moisture and high levels of sound pressure than their Condenser counterparts.
- This makes them a popular choice for vocalists on stage and situations where they can be treated roughly.
- They don't require a power source

CONDENSER MICROPHONES:
- Much more delicate design
- To make sure they have a long life and always maintain a high recording standard they have to be treated with care, kept away from moisture and not bashed around.
- They require a power source (batteries or phantom power)
- When kept well they can pick up a very high standard of recording.

RIBBON MICROPHONES:
- A type of dynamic microphone which is heralded by many as the most natural sounding microphone ever created.
- Extremely fragile and can be damaged by harsh levels of sound pressure
- They do not need a power supply
- Ribbon Mics were very popular in the broadcast industry but more recenly there has been a shift towards condenser microphones as they pick up a high level of recording but are much cheaper to buy.

Then there are piezo-electic mics (low quality used in telephones), clip mics, booms, crystal mics and on.......do your research!

DIRECTIONAL RESPONSE and FREQUENCY RESPONSE:

Different microphones have different Polar Patterns. This is the response they have to sounds from various directions. The frequency response shows which mics will pick up the frequencies that you want. So for example if you are recording a female voice its much better to have a microphone that caters for the rough fundamental frequency of a female voice (around 165 to 255 Hz). Here are the main types of directional response you will experience:

Omnidirectional: This theoretically pics up sounds 360 degrees around the microphone. Good for picking up a natural room ambiance.
Cardioid: This means that the mic has a directional response that favors the front and it will pick up less sound from the sides and almost exclude sounds from the rear.
Super Cardioid: Similar to the Cardioid but it has a wider pick up and also pick up some sound from behind.
Hyper Cardioid: Again similar to the Cardioid but extends the pick up further in front to the sides and lets in more noise from the rear although favors the front.
Bi-Directional: Also known as a "figure of eight". Picks up sound pressure equally from in front and behind but will exclude sound from the sides.
Shotgun: Highly directional to the front and rear. Favors the front and excludes the sides.

Get on to Celine's People and rearrange that interview and invest in some headphones, then at least you can hear it going wrong!

Here is a BBC take on the use of microphones