I need some help understanding Mics

[John]

Mics that amplify the signal before sending it thru the cable are called condensor mics? Do these mics have a cleaner sound? To get a cleaner sound, it seems like I would want all my mics to amplify the signal before sending it?

When you have a box on the stage connected to a fifty foot snake, does the box amplify the signal before sending it? It seems like 70 feet (50ft snake + 20ft cable) is a long way for an unamplified signal to go? It seems like a stronger signal would be less likely to pickup other noise (static, crosstalk, radio, etc.)?

- John.

[St0rMl0rD]

ya mon 8)

[Digilog]

Mics that amplify the signal before sending it thru the cable are called condensor mics? Do these mics have a cleaner sound? To get a cleaner sound, it seems like I would want all my mics to amplify the signal before sending it?

When you have a box on the stage connected to a fifty foot snake, does the box amplify the signal before sending it? It seems like 70 feet (50ft snake + 20ft cable) is a long way for an unamplified signal to go? It seems like a stronger signal would be less likely to pickup other noise (static, crosstalk, radio, etc.)?

- John.

Condenser Mics don't really amplify the sound before sending the signal; they just use a different method the turn air pressure into a signal than a dynamic mic. Condenser mics have a capacitor that holds a 48v charge (phantom power). As the diaphragm on the mic moves, the charge in the capacitor changes. The signal is then constructed based on how the charge in the capacitor changed. Condenser mics are known for capturing more detail than dynamic mics.

To combat this noise problem that you mention, balanced cables are used. Balanced cables go off of the principal that if a signal and an inverse of that same signal are added together, you get 0 or silence. The inverted signal is commonly known as 180 degrees out of phase.

A mic cable has 3 prongs. One is a ground, one is the signal, and the other is a copy of the signal. As the signal leaves the first balanced device, the phase is flipped on one of the copies of the signal. It is assumed that both copies will pick up the same noise as they travel the length of the cable. When the signal reaches the destination device, the phase is flipped again so the copies are in phase again and will not cancel one another. The noise that was picked up along the cable however is now out of phase and is completely canceled when the copies are summed together.

[metropolis2k]

Ignore that um... 'post'

Condenser mics need power to work. They can get this power either from a battery inside the mic, or something called 'phantom power'. You may notice many mixing desks can send phantom power. To get the phantom power to a mic you need to send it down a balanced cable to the mic. Otherwise it won't give you the levels you want.

Condenser mics are more sensitive than dynamic mics and are more suited to things like recording piano, vocals, acoustic guitars and more ambient sounds (like a jazz band or an orchestra).

EDIT - Digilog beat me to it! - my first comment was in response to the first reply in this thread for the record.

[Over The Edge]

Anyone know how a ribbon mic works. Not too
familiar with those. I hear they're great for
recording brass and winds.



FL
www.franklucas.net

[John]

So how far can a mike cable go & still have a good sound?

[John]

Is there a decent condeser mic that cost less than $100 USD?

[Spacehog]

You could probably find a Behringer B1 for under $100 if you looked hard (they retail for $119) - I've got one, I used it for all vocals and acoustic guitar on my last album, sounded great. Not for stage use though (except perhaps drum overheads) as it's far too sensitive and would feed back. For stage use you'd be looking for a specifically designed stage condenser, either a back electret one like the AKG C1000S or Shure PG81, or some of the rugged (but expensive) condenser vocal mics like the Shure Beta 87.

Martin

[Digilog]

A ribbon microphone has a thin strip of conductive metal (the ribbon) and a magnet on either side of this metal strip. The magnets create a magnetic field around the metal strip so that when the metal strip is exited by sound waves, a current is induced into it.