Hi ,
I use Cubase 7.5 32bit on my macbook pro , i want to upgrade it to 64bit . First of all , if I install it will it keep the 32bit Version ? can it cause any issues ? and in general any feedback on that version ?
On my PC i had too many issues with the 64 bit .
Thanks in advance 
On a MAC Cubase 7 is both 32 and 64. You don’t need to “upgrade”.
Be sure that Cubase is closed. If you go to the application folder and use the MAC “info” function on Cubase you will get an information box with lots of information, among it you will find a tick able box for 32/64 bit. Next time you open Cubase it will open according to what you choose.
32/64 bit is a memory issue, nothing else, and how much memory you can utilize depends on which OS you are running and how much memory you have installed. If you run Cubase in 32 bit it will not be able to utilize more than approx 3,5 GB. If you run it in 64 it is virtually endless how much memory Cubase can utilize. However it cannot utilize more than what is installed. From Maverick OS and newer (Yosemite) in the MAC you can utilize all your memory to the application. Previous OS set aside 1/3 of the memory for “unforeseen tasks” so If you had installed 6 GB Cubase could only utilize 4 of them. So be sure you have at least more than 4 GB of memory and that you run at least Maverick, otherwise 64 bit is hardly any point, unless you exceed the memory limit of 6 with an older OS. Be aware that not all older plugins will run under 64 bit or newer OS and won’t run in any bridge either.
Thanks !