A compressor allows you to compress your audio and bring out things that aren't as loud without making the things that are loud any louder. Essentially you are taking the dynamics away from the music. Depending on the genre this can be good or bad. In classical music there are a lot of dynamics. When the entire orchestra is playing the music is loud, but when it breaks down and its just the flutes playing it gets very quiet. Using a compressor you can make that louder. In this scenerio you wouldn't want to do it because that's a part of Classical Music having that dynamic range. When you come to Pop Music everything is compressed to hell to make the track as loud as possible. On an individual track such as a vocal track you can use a compressor to even everything out. So that one part of the recording that the artist doesn't sing as loud can be compensated for without having to re-record the entire track.
see Yamaha's Sound Reinforcement Handbook by Gary Davis
Volume levels are altered by broadcasters to attract your attention during ad breaks. The device you need is called an audio compressor, or automatic volume controller (AVC). Take the audio output from the TV via the headphone socket to cut out the TV speaker. Insert compressor in series with aux input on an audio amp and listen via home cinema system.
I use a tool called "Audio Compressor". Use a search engine to find one on the internet.
Sidechaining is where you have two signal, A and B and the signal B affects how signal A is processed. For example if you have a kick drum and bass track, if you put a compressor on the bass track and send the kick drum to the side-chain of that compressor, the compressor will act by how the kick drum plays, and thus gives more room for the kick to cut thru the mix as the bass ducks when the kick drum hits.
Note:The accumulator/drier should be replaced whenever the compressor is replaced Caution:On models with a Delco Loc 2 or Theftlock audio system be sure the lockout feature is turned off before proceeding * Have the AC system discharged.Disconnect the neagtive battery cable * Clean the compressor thourghly around the refrigerant line fittings * Remove the serpentine belt * Raise and support it securely vehicle on jackstands * Disconnect the electrical connector from the AC compressor * Disconnect the suction and discharge lines from the compressor.Both lines are mounted to the back of the compressor with a plate secured by one bolt.Plug the open fittings and discard the seals between the plate and compressor * Unbolt and remove the rear compressor mount.It may be necessary to remove the right side engine mount bolt and raise the engine to access the rear compressor mount bolts * Remove the compressor to front bracket bolts and nuts and remove the compressor from the engine compartment
Note:The accumulator/drier should be replaced whenever the compressor is replaced Caution:On models with a Delco Loc 2 or Theftlock audio system be sure the lockout feature is turned off before proceeding * Have the AC system discharged.Disconnect the neagtive battery cable * Clean the compressor thourghly around the refrigerant line fittings * Remove the serpentine belt * Raise and support it securely vehicle on jackstands * Disconnect the electrical connector from the AC compressor * Disconnect the suction and discharge lines from the compressor.Both lines are mounted to the back of the compressor with a plate secured by one bolt.Plug the open fittings and discard the seals between the plate and compressor * Unbolt and remove the rear compressor mount.It may be necessary to remove the right side engine mount bolt and raise the engine to access the rear compressor mount bolts * Remove the compressor to front bracket bolts and nuts and remove the compressor from the engine compartment
Note:The accumulator/drier should be replaced whenever the compressor is replaced Caution:On models with a Delco Loc 2 or Theftlock audio system be sure the lockout feature is turned off before proceeding * Have the AC system discharged.Disconnect the neagtive battery cable * Clean the compressor thourghly around the refrigerant line fittings * Remove the serpentine belt * Raise and support it securely vehicle on jackstands * Disconnect the electrical connector from the AC compressor * Disconnect the suction and discharge lines from the compressor.Both lines are mounted to the back of the compressor with a plate secured by one bolt.Plug the open fittings and discard the seals between the plate and compressor * Unbolt and remove the rear compressor mount.It may be necessary to remove the right side engine mount bolt and raise the engine to access the rear compressor mount bolts * Remove the compressor to front bracket bolts and nuts and remove the compressor from the engine compartment
Note:The accumulator/drier should be replaced whenever the compressor is replaced Caution:On models with a Delco Loc 2 or Theftlock audio system be sure the lockout feature is turned off before proceeding * Have the AC system discharged.Disconnect the neagtive battery cable * Clean the compressor thourghly around the refrigerant line fittings * Remove the serpentine belt * Raise and support it securely vehicle on jackstands * Disconnect the electrical connector from the AC compressor * Disconnect the suction and discharge lines from the compressor.Both lines are mounted to the back of the compressor with a plate secured by one bolt.Plug the open fittings and discard the seals between the plate and compressor * Unbolt and remove the rear compressor mount.It may be necessary to remove the right side engine mount bolt and raise the engine to access the rear compressor mount bolts * Remove the compressor to front bracket bolts and nuts and remove the compressor from the engine compartment
Note:The accumulator/drier should be replaced whenever the compressor is replaced Caution:On models with a Delco Loc 2 or Theftlock audio system be sure the lockout feature is turned off before proceeding * Have the AC system discharged.Disconnect the neagtive battery cable * Clean the compressor thourghly around the refrigerant line fittings * Remove the serpentine belt * Raise and support it securely vehicle on jackstands * Disconnect the electrical connector from the AC compressor * Disconnect the suction and discharge lines from the compressor.Both lines are mounted to the back of the compressor with a plate secured by one bolt.Plug the open fittings and discard the seals between the plate and compressor * Unbolt and remove the rear compressor mount.It may be necessary to remove the right side engine mount bolt and raise the engine to access the rear compressor mount bolts * Remove the compressor to front bracket bolts and nuts and remove the compressor from the engine compartment
Note:The accumulator/drier should be replaced whenever the compressor is replaced Caution:On models with a Delco Loc 2 or Theftlock audio system be sure the lockout feature is turned off before proceeding * Have the AC system discharged.Disconnect the neagtive battery cable * Clean the compressor thourghly around the refrigerant line fittings * Remove the serpentine belt * Raise and support it securely vehicle on jackstands * Disconnect the electrical connector from the AC compressor * Disconnect the suction and discharge lines from the compressor.Both lines are mounted to the back of the compressor with a plate secured by one bolt.Plug the open fittings and discard the seals between the plate and compressor * Unbolt and remove the rear compressor mount.It may be necessary to remove the right side engine mount bolt and raise the engine to access the rear compressor mount bolts * Remove the compressor to front bracket bolts and nuts and remove the compressor from the engine compartment
Note:The accumulator/drier should be replaced whenever the compressor is replaced Caution:On models with a Delco Loc 2 or Theftlock audio system be sure the lockout feature is turned off before proceeding * Have the AC system discharged.Disconnect the neagtive battery cable * Clean the compressor thourghly around the refrigerant line fittings * Remove the serpentine belt * Raise and support it securely vehicle on jackstands * Disconnect the electrical connector from the AC compressor * Disconnect the suction and discharge lines from the compressor.Both lines are mounted to the back of the compressor with a plate secured by one bolt.Plug the open fittings and discard the seals between the plate and compressor * Unbolt and remove the rear compressor mount.It may be necessary to remove the right side engine mount bolt and raise the engine to access the rear compressor mount bolts * Remove the compressor to front bracket bolts and nuts and remove the compressor from the engine compartment
Note:The accumulator/drier should be replaced whenever the compressor is replaced Caution:On models with a Delco Loc 2 or Theftlock audio system be sure the lockout feature is turned off before proceeding * Have the AC system discharged.Disconnect the neagtive battery cable * Clean the compressor thourghly around the refrigerant line fittings * Remove the serpentine belt * Raise and support it securely vehicle on jackstands * Disconnect the electrical connector from the AC compressor * Disconnect the suction and discharge lines from the compressor.Both lines are mounted to the back of the compressor with a plate secured by one bolt.Plug the open fittings and discard the seals between the plate and compressor * Unbolt and remove the rear compressor mount.It may be necessary to remove the right side engine mount bolt and raise the engine to access the rear compressor mount bolts * Remove the compressor to front bracket bolts and nuts and remove the compressor from the engine compartment