Audio Engineering: Mixing and Parameters

Recording
The recording process in Audio Engineering is hands-down the most important part. If you can record a good signal at good levels with the right acoustics than the rest of engineering is so much easier. A good level is about 3/4 of the wave bar is filled with a waveform. This leaves extra room for any wild/unexpected signal burst. This also is important for using your compressor so that it doesn't distort.

Compressor
The compressor is used a lot in Pop and Hip-hop. This takes your signal and expands the low parts and shrinks the intense ones. Over compression can sound very mechanic like. Too many people rely on the compressor instead of using automation with levels, thus making the recording sound like it came out of a can or plastic wrap. You should use the compressor to control you levels, not to shape a sound.

Reveb
Reverberation is basically a short echo in easy terms. In is used to give natural depth to a signal. On vocal it is used to blend the signal with the rest of the instrumentation. Most problems with this are in rock or live instrument recordings. Too much reverb can confuse the song, but in some cases that is used to it's advantage. Reverb was once used on drums a lot, mostly to make it sound big and deep. Present time it is not used as heavy. The problem with inexperienced Pop or Hip-hip is that it is not used enough. Vocal often sound like they were recorded and not touched at all. Makes for a very unprofessional recording.

Delay
This is the echo. The biggest problem is that this is not set to tempo. In some cases you might want the echo to be off tempo or ambient but in 99% of the time it should be on. Knowing the BPM of the song is very important for Delay, Editing, Reverb, ect... finding out how to use the right parameters can be found here.

www.sengpielaudio.com/calculator-bpmtempotime.htm

EQ
This is probably the most overused parameter of all. Most people try to fix a signal mostly vocals by adding frequencies. That is not always the correct way of using this, especially when you are add final touches to a mix. This tends to double total frequencies of the whole song. What is just as important is subtractive mixing. Taking annoying frequencies is a good tool in clearing up space in a mix. Sound-on-sound is a good tool to use as a beginner.

www.soundonsound.com/sos/jun01/articles/vocalsfaq.asp

There is much more to recording and mixing but these are some obvious mistakes that untrained engineers have.