tubesrawsom said:
if i use aux wont i have to use an extra channel for the compression
I think you misunderstood what mixsit is stating about auxes.
Auxes are basically used for signal "effect" processors such as 'Verb's, Chorusing, Delay's etc. to the desired signal while your INSERTS are used to connect signal "dynamic" processors such as comps and eq'lizrs.
In particular, please note that compressors are not designed or used as a "effect" device (unless you're using a 3630
) per se, but to control a signal's dynamics where needed such as peak control,compression, response, leveling, etc. along with gating, de-essing and normalizing functions.
Your question on comp application as either "inline" or "loop"
indicates you need to take the time out to learn and understand the basics of compression and use of same. Believe me, I'm not trying to belittle you or come off as some-1 who's holier than thou, it's just that years back, I ran my 1st ever comp thru the auxes thinking thats the way it was w/o giving myself the benefit of understanding the unit's purpose. At least you have inquired about it's connection, now take it a step further and learn ias much as you can about it!
Peace
Q.rM