Here are a few mastering compressor tips from my book Mixing And Mastering With T-RackS: The Official Guide that I don't think you'll find anywhere else.
"Adjusting the Attack and Release controls on the compressor and/or limiter can have a surprising effect on the program sound.
- Slower Release settings will usually make the gain changes less audible but will also lower the perceived volume.
- A slow Attack setting will tend to ignore drums and other fast signals but will still react to the vocals and bass.
- A slow Attack setting might also allow a transient to overload the next plug-in or piece of equipment in the chain.
- Gain changes on the compressor caused by the drum hits can pull down the level of the vocals and bass and cause overall volume changes in the program.
- Usually only the fastest Attack and Release settings can make the sound “pump.”
- The more bouncy the level meter, the more likely that the compression will be audible.
- Quiet passages that are too loud and noisy are usually a giveaway that you are seriously over-compressing."
You can read more from Mixing And Mastering With T=RackS and my other books on the excerpt section of bobbyowsinski.com.