Hello Buddy. I cannot speak for logic but i can speak for protools. Protools is the industry standard DAW (digital audio workstation). I would only ever consider it for mixing and making music first and foremost above all other DAW softwares.
RAM greater than 4gb will NOTeffect your DAW or mixing performance at all. Protools in its current 32bit state only utilizes 3.4-3.6gb RAM total. (however getting 8gb RAM is not a bad idea since it so cheap, but it will not "boost" your DAW performance) Therefore anything above that will not be used in your protools mix. Im not sure if logic utilizes more RAM than that or not but protools currently does not.
I would get the mac mini server version with quad core. Reason being: you will be able to move you studio and get any sized external monitor you want and wont have to be married to a 21 or 27" imac screen every time you need to hit the road.
DAW's are processor heavy and are not RAM intensive like video or graphic design. The only way your DAW when running protools uses more than the previously spoken about 3.4-3.6gb RAM is when using virtual instruments that are not in AVID or digidesing sample libraries. Something like a addictive drums or BFD drums are sameple libraries and virtual instruments and their samples are pulled up in RAM while the CPU is processing the sounds. These would utilize the extra RAM aboce the 3.6gb RAM, NOT the DAW.
IMPORTANT: Protools is NOTcompatible with Lion as of yet! (I assume logic LE is not either) Protools is NOT capable with Server versions of OSX either. most audio interfaces that are USB or firewire also are NOT yet compatible with Server OSX or Lion as of yet.
NOTE: the i7 mac mini server is not a 2.7ghz i7 processor as per your first post, it is only a 2.0ghz i7 btw.
IF you do decide to get the 2011 mac mini server with quad core, you will have to purchase a snow leopard retail installer disc. Install snow leopard to an external harddrive as your boot volume. Back up the external hard drive boot volume using time machine on a separate or partitioned pard of this external drive and then restore that backup back on to your new mac mini thats currently loaded with lion. You CANNOT merely install snow leopard onto the new mac mini , the mac will now let you do so. You will get errors everytime you try, you must "fool: the mac and "force" it to revert to an earlier OS such as snow leopard. You CANNOT run protools on lion and you CANNOT run protools on a Server OS. You will get errors all day and all night. the way i described is the ONLY way to run this. Trust me from experience.
When you do you get your DAW set up on the mac mini. Its nice because you can partition the other drive to run lion still if you want and then you can use the 2nd drive that has lion installed on it as your record version and it will run Waaaay better than any USB external drive or firewire drive. This is very convenient compared to the imacs but can take days to set up. Time machine and the the snow leoopard retail version Disc is key though. I use a mac mini server my self and have dealt with this for months including expensive technical phone calls for support.
I have a lion OSX set up on my mac mini and a 60GB partition set up on the second hard drive running snow leopard. Protools projects are saved to the Lion hard drive when booting form the snow leopard side.
you will continue to run into these issues when upgrading or changing equipment when dealing with audio recording. Your best bet is to pick a great system that works, put it on a partitioned drive and dont update or change anything until the host application (AVID/protools in this case) is absolutely ready for a change.
I hope this helped and did not confuse the crap out of you!
Jordan
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