Battling noises might just be the hardest thing a podcaster deals with, I my self live about a mile from a private Airport and am inline with the planes that love to play touch and go (A fake landing).
Among the noise coming from TV’s, fans and surprise guests, they like to play a key roll in my podcasts, in this blog post I will tell you how to lower/eliminate noise that is being picked up in your recordings.
1 The first line off defense is your microphone, their are 3 types of microphones out there that we need to cover, Condenser, Dynamic, and Ribbon microphones.
Most podcasters cant afford ribbon mics due to the fact that the price tag ranges around $900+, so I’m only going to use the other two (Condenser and Dynamic).
Condenser Microphones
Condenser Microphones are almost as common as the cold, and when it comes to picking up noise Condenser microphones are the worst. Condenser microphones are used in a lot of consumer products, from a cellphones, Webcam Microphones, and the cheap $10 headset/microphone combos. Condenser’s love to pick up everything, Why?
Condenser microphones capture sound using a conductive diaphragm with a capacitance charged plate behind it. The charge is supplied by a DC voltage source from a battery or from the 48 volt ‘phantom power’ supply present in most mixers and mic preamps. Air pressure changes meeting the conductive diaphragm cause it to move, which causes an analogous AC voltage to be formed in the charged plate. These tiny AC voltages are sent to a tiny preamp built into the microphone, which brings the signal level up to where it can drive a typical microphone preamp. This is why a Condenser microphone picks up ALOT of noise.
So the trick with this type of microphone is to turn the volume down, buy a pop filter, and talk closer into the mic.
This will eliminate about 75% of all noise.
I have a friend that owns a CAD GTX2200 Condenser Microphone, Not a bad mic, he sounds great on it, but the problem is not the mic, it is the phone and bird about 20 feet away. By doing this it eliminated the phone and took the volume of the bird so low, we where able to record a distant podcast with out the recording being pegged when the bird talks.
Dynamic Microphones
Thank you god! Dynamic microphones do not have problems like condensers. Why? well Dynamic mics use a ‘moving coil’ to sense the changes in air pressure that makes sound waves. The wire coil is connected to a thin diaphragm, and the whole assembly is suspended over a permanent magnet. When moving air hits the diaphragm it causes the coil to move over the magnet, which causes a process called electromagnetic induction to take place. This causes an AC voltage to be formed that is an electrical ‘analogy’ of the original sound and lowering the noise being sent. This is why you have to what we call eat the microphone for your self to be heard.
although a fan or a loud noise can be picked up from this type for microphone its a lot less then Condensers
2 The second line of defense is a mixer. A normal mixer Has a Gain, High, Mid, Low and Vol nobs or sliders.
the first is gain when dealing with noise you will be dealing with this and the vol. you want to dial this in to where you dont hear any noise, but sill can record at a decent volume.
High, Mid, and Low are freq for your voice Highs tend to bring in some noise and give your voice some warmth, Mids tend to just stick around, unless you have a bass voice. And then you have Low… Low is what you would expect from the word, the low end of your voice, If you want a bassy voice but you sound like a chipmunk, the low nob should help you out.
3 Among all the great hardware that helps someone to eliminate noise is is the third line of defense a Gate/Limiter/Compressor. What the gate does is keeps the microphone off until it hears a signal at the level you have set, Limiters do as what the name describes Limits the ammout of audio, and Compressors keeps the volume at a consent level as to not clip or peek the recording/performance. The Cheaper ones you can buy only come with Compressor/Limiter and or a Gate, but you can be purchased with all three.
4 The forth line of defense is you, Take the time and close the windows, turn off the fans, give the kids $10 for the Ice Cream Man/Lady, lock the dog up, memorize the train schedule, etc. Things are going to happen, and that is why God made a pause button.
As a word of advice the closer the better, is to reduce background noise .
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