Quick questions, with answers
A selection of questions recently received by Audio Masterclass...
"I don't really understand what mono and stereo mean. Can you explain?"
Mono is Greek for 'one'. In essence it means one microphone connected to one preamplifier, recorded on one channel and fed to one loudspeaker.
Stereo comes from the Greek for 'solid'. We normally consider stereo to mean two microphones connected to two preamplifiers, recorded on two channels and fed to two loudspeakers.
In stereo, there must be at least two channels all through the signal chain from microphones to loudspeakers. If at any point the two signals are combined into one, then the result is mono, even if reproduced through two speakers.
"There is always a feedback when using a capacitor mic in a small hall unlike when using a dynamic mic, how true is this?"
This is not true in principal. However there are more dynamic microphones that are designed for public address use than capacitor microphones. In general, you will get better results from microphones that are designed for live sound.
"The gain function; is it only used in increasing the volume of a particular channel or there is any other function it works for?"
It is used to bring the incoming signal level up to the normal signal level required by the mixing console. Typically this could mean boosting the 10 millivolts or so produced by a microphone up to around 1 volt.
The gain control has no other function.
"What is surround sound, width, presence, warmth, and side to side difference?"
Surround sound: Stereo, but with more channels and more loudspeakers.
Width: In conventional two channel stereo, the subjective distance between the sound coming from the left loudspeaker and the sound coming from the right loudspeaker. If the signal is mono, then subjectively the width will be zero and the signal will appear to come from a point halfway in between the loudspeakers.
If the width is normal - i.e. a stereo pair of microphones has been set up correctly, OR the various channels contributing to the mix have been panned evenly, then there will be subjectively an even spread of sound between left and right.
If, for instance, a recording has been made with two microphones spaced apart by a long distance, then sound will subjectively 'cluster' around the left and right speakers, with little sound appearing to come from in between.
Warmth: A very subjective quality. A sound that is warm tends to be rich and full-bodied. There may also be a slight but pleasant distortion.
Side to side difference: Not a phrase in common use. Could possibly refer to an imbalance in the level between the left and right channels.
"There are some mixing consoles that have hi freq and its gain, hi mid and its gain, low mid and its gain,and low freq and its gain while some have just hi freq, mid freq and its gain and low freq. is there any difference in sound quality of this two console?"
There isn't necessarily any connection between features and quality. It is good to have versatile features, it is also good to have high audio quality.
"Why is it that the two overhead mic doesn't need much gain?"
Presuming this refers to drum overheads, it is because the drums are bloody loud!
That's all. For now...