The 64 bit question.
A 64-bit operating system for the computer is one thing - most new ones come w/ it. If the OS is 64-bit, use SONAR's 64 bit version.
The 64-bit engine within SONAR (engaged with the little button in Options>) basically upsamples the processing. Can you hear the difference between 32 and 64 bits? Probably not. It allows for less rounding errors in the processing, so there might be less ring in a reverb or similiar lack of artifacts, but it will be extemely small. However, in the old days (which weren't always so good) a lot of the better effects did internal upsampling. This was in the 16 or 24 bit world, and this helped expensive 3rd party effects get a good reputation.
many of us use 24 bits to capture - which is what an interface can do. It is stored as 32 bits (that is what many of us use, anyway). However, when you engage the 64-bit engine all the mixing and effects are done at 64 bit. It works for me (and others on the forum when we have had this conversation). In the old days that would have choked a single processor. Today, mulitple processors do the math easily. My old double chip computer worked fine w/ the 64 bit engine.
Personally, I haven't noticed any problems w/ the 64-bit engine engaged. But here at home I usually don't run big projects and even if my projects have a lot of soft synths I ususally freeze them and archive the synths themselves so I can chop and dice the audio only. So if you are having dropouts/clicks etc. w/ X3 turn the 64 bit engine off. At least until Cake gets a fix. As said above, I doubt you'll hear a difference, even when it gets fixed. But up until now ... why not use the better engine? And after it gets fixed, why not? Something about removing the grain of sound out of the eye of your reverb ;-)
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