Whilst in theory I understand the differences between a 32 & 64 bit O.S. in practice the distiction between the two is somewhat blurred in my head !
 
So a 64 bit chip requires a 64 bit O.S. and software needs to be optimsed to take advantage of the 64bit O.S. So my question is
 
1 'If you have a 64 bit O.S. should you always install the 64 bit version of software, or does it depend on other things such as 32bit plug ins not being available or just harder to get to work (although from a short scan of forum even that is 'fixable') '
 
2 Is the supposed performance difference noticeable (and therefore worth any a trouble it takes to set up)
 
 

I wouldn't say a 64 bit chip meaning CPU must run a 64 bit OS. It will but it will also run a 32 bit OS. 
 
With 64 bits you get access to a lot of memory.  32 bits is limited to 4 Gb total. Because processing is at 64 bits instead of 32 bits things are a bit faster. 
 
I haven't found it a problem now not using 32 bit VSTs. I almost exclusively use 64 bit plugins. What few 32 bit ones I have work fine under Bitbridge.
 
One neat thing about this is you can install both 64 bit and 32 bit Sonars without any problems on the same machine. 
 
 

You say 64 bit is faster than 32 bit, however I was once told that unless the increase in speed is over 13% then it is generally not noticed
 
Also  my machine only has 4GB of memory so there appears to be no discernable advantage to a 64 Bit OS ?

Being a keyboardist and a Kontakt owner I really need the higher RAM addresses. Some of the drum kits take up over a gig, you start adding in other samples and you can run our of RAM quickly. I've been 64 bit with SONAR for the better part of 4 years and haven't looked back. I still use the occasional 32 bit vst, but SONAR's integration with 3rd party jBridge makes it easy. 
 
There are other advantages to being 64 bit with the various plug-ins, but I'm not qualified to speak to those so I won't. I'm sure some other forum members can chime in and give you an explanation.
 

IfItMovesFunkIt
You say 64 bit is faster than 32 bit, however I was once told that unless the increase in speed is over 13% then it is generally not noticed
 
Also  my machine only has 4GB of memory so there appears to be no discernable advantage to a 64 Bit OS ?

For you no. Sorry.

The 13% boost in  performance is about right, over a 32-bit chip. There's no advantage, for a DAW at least, to be 32-bits, so going with the 64-bit version keeps you current. Sonar will run 32-bit plug-ins, so there's no major negative there.

The only real performance difference you will see is that Kontakt libraries (and other sample-based VSTi's) will run better IF you also have a lot of RAM. If your machine only has 4GB (or less), 64bit OS will hurt rather than help you.
 
On the other hand, 64bits is the future and 32bit releases will eventually fade away, so you'll need to get there someday.
 
Regards,
Dan
 
 
 

Most 64 bit operating systems will require more memory resources than the 32 bit systems just to run the OS. So there may well be an advantage in using 32 on a 4 GB system. The basic requirements for RAM in Windows is 1 GB for the 32 bit system, 2 GB for 64. If I were limited to 4 GB of memory, I would go 32 bit.

Programmer here. A 64 bit chip allows you to run a 64 bit operating system, which is required for 64 bit versions of software.
 
A 64 bit version of any given piece of software is intrinsically going to differ from a 32 bit version in 2 key ways:

1. It can access much more memory, which means it can hold a lot more information at once - providing that enough memory exists (ie. your computer has enough RAM)
2. If all else is equal, it will tend to be slightly slower because the code and data is slightly bigger. (Each memory address is twice the size.) However, all else is not usually equal - as running a 32bit app on a 64 bit OS incurs its own (small) slowdown. Unless you are installing an OS purely for your DAW and need every last percentage point of speed, it doesn't matter.

For almost all purposes, point 1 outweighs point 2. Extra memory tends to speed things up, if you ever find yourself without enough of it.
 
However, Sonar is one of a very small number of apps that needs to host other programs inside it, ie. VSTs. If those VSTs are 32-bit, they can't be used directly with 64-bit Sonar, which is where Bitbridge comes in.
 
For a typical musician, if you have enough memory (over 4GB), and you don't have any 32-bit plugins that are essential to your workflow AND which are known to not work well (or at all) with Bitbridge, you should upgrade.
 
If you have 4GB or less, you'll see very little benefit, and maybe some problems. (But if you have 4GB or less, you won't be able to run memory-intensive samplers, which are probably the main thing that benefit from 64 bit systems.)

I noticed immediately after switching to 64 bit throughout when setting up a new orchestral template, using EWQLSO Platinum.
Previously, running 32 bit, the maximum number of instances of the old Kompakt player i could load was 14, giving me a realistic number of audio + midi tracks to about 20
 
Now, my template consists of 135 tracks, including about 35 midi tracks dedcated to key switching.
My system doesn't even blink when editing/playing/mixing.