I can hear the difference between Peak compression and RMS compression - RMS seems to make the audio MUCH louder when compared to peak. It was only just moments before posting this I finally understood what RMS is and it all seems related to speakers - so I think I see the correlation, but if someone could expand on it I would appreciate it.

http://www.soundonsound.com/sos/dec00/articles/adcompression .htm

half way in they talk about it

One simple way of thinking about RMS-compression is that it compresses the loud parts (what we HEAR as loud) instead of the peaks (which we do not necessarily hear as loud).

Another way to think of it is that it is "slower"...You can kinda think of RMS as an average over (a short) time.

Its of course not nearly as simple, but i mostly use peak for "envelope shaping" and RMS for "loudness levelling".

Ah, yes.
the link and j79's response seemed to help me out in understanding it. So, then I guess, ideally, I would want to use RMS on drums if I want to retain their excitement?

Not really as simple as that. "Excitement" is a subjective term that will mean different things to different people. The "best" settings for the drums will also depend on the context: the drums need to fit the rest of the mix.

If you want to make your drums sound "fatter" (another subjective term, but more specific than "exciting") you will probably want a fast peak sensing compressor design capable of catching short transients. However, you are just as likely to be compressing your drums to make them "snappier" or "punchier" in which case you want a slower attack time so that transients are shaped by the attack of the compressor, rather than just smashed. In this case you might get the sound you want by using a peak sensing comp again, but with a slower attack. Or you might prefer the different type of transient shaping that will be provided by an RMS design.

If you want a simple rule of thumb: "fat" drum sounds will probably require a peak sensing compressor, while "punchy" drums might need a peak sensing design with a carefully tuned attack time, or an RMS design depending on your starting point and the sound you are trying to achieve.

Sorry for not clarifying that, but excitement I mean that attack on the drums to make them punchy.
In most cases I have used peak compression with a very slow attack and about a 60/40 mix (w/d) to me it seemed to keep a good amount of punch, but would it be more beneficial to do punchy with RMS compression?

I don't know. I can't hear the drum sound you're starting with, nor can i hear the sound in your head that you're aiming for. I suggest you try both (in context) then make an aesthetic choice.

Question: how do i get from a to b.
Answer: it depends, where is b, and where is a?

Well I suppose I can feel a nice powerful attack that isn't compressed much, so I suppose whatever I am doing is doing it right which usually was related to peak compression.

thanks for the answers. Guess we can call it a wrap.