Masters Program - Lesson 2 - Posted on 2014-03-03 by Collin McCombs

Lesson 2 was about compressors in depth. I liked this lesson a lot because I was able to understand the concept compresson more and get my hands on all the compressors at Cypher. Compressors control the smoothness of the dynamic range of an audio signal and are extemely important in audio engineering. Most compressors usually have parameters like gain, threshold, ratio, attack, release, and possibly a knee. On day one Aaron and I went over the five different types of compressors. The first one we talked about was a Variable-U compressor. Variable-U compressors use vacuum tubes and are known for their smooth compression and warmth. Next we discussed Optical compressors. Optical compressors emit light that is then recieved by a photosensitive device that controls the output signal. Basically the compressor uses the intensity of the optical energy to control compression. After that we went over Feild Effect Transistor (Fet) compressors. They are similar to Variable-U compressors except they use solid-state components instead of tubes. These compressors typically have configurable knees, and attack and release times like Diode Bridge compressors. Bridge Diode Compressors at similar to FET Compressors but are tonally distinctive because of the non-linearities in the diodes. Next we talked about Voltage Controlled (VCA) compressors. This is definitely one of the most versatile and most common types of compressors, known for there high degree of linearity. Feed-Forward compressors, typically used in mastering, use the side-chain for the input of the compressor. This special type of design uses a small delay in the signal path allowing the audio to be processed so the compressor has time to adjust how much compression will be applied. Feedback compressors split the output of the signal and feeds it back into the side-chain to control the amount of compression that will be applied to the signal. In othe words the compressor reacts to the signal that has already been through the compressor, rather than reacting to the signal as it is about to arrive. After that we discussed Serial compression. Serial Compression is when a signal goes out of one compressor, and is then sent to a second compressor. An example of serial compression is when you are using  a compressor and and then sending that signal into a de-esser. The last thing we talked about was Multi-band Compressors. Those compressors use different frequency bands to apply various ammounts of compression to certain frequencies. On day two I experimented with all the compressors at the studio. The first one I wanted to use was the SSL compressor. To do that I opened up a practice session and soloed to lead vocal track. Once that was done I engaged the dynamics section into the signal path and then set the threshold, ratio, and release times. Aaron then told me when he is working with vocals he usually sets up a small gate because that helps a lot with breath noise. After that I disengaged the dynamics section and patched in the the dbx 160A, then inserted it in to the signal path. I then adjusted to threshold and ratio before increasing the gain for the right amount of compression, which is six to eight decibels of gain reduction. I then did the same thing for Summit Audio MPC-100A tube compressor, Summit Audio TLA-100 tube compressor, and then my favorite the Universal Audio LA-610 optical compressor. This lesson was extemely helpful and I can't till next week when I'll learn about SoundReplacer and Drumagog.