[NOTE: At present I am running Mac OS X 10.8.3 (Mountain Lion) . . . ]
BACKGROUND
With NOTION 3 on the Mac, I did a series of experiments and determined that leaving the Audio Buffer Size at the factory default of "256 Samples" worked best on the 2.8-GHz 8-core Mac Pro (early-2008) with 8GB of memory, and this logic was similar with the Digital Performer 7 (MOTU), which also is a 32-bit application, although for Digital Performer 7 the correct values were Buffer = 512 and Multiplier = 1, which worked nicely with ReWire 1.7 (32-bit only), as well . . .
And since I like the rule that when something is not broken, it tends to best to avoid fixing it, I did not revisit the buffer settings initially when everything switched to 64-bits and I increased the memory on the Mac Pro to 20GB, but this week I noticed that there were "clicking and popping" noises after every note played by the NOTION 4 Bundled Electric Bass, which also happened with the MachFive 3 (MOTU) Jazz Bass and String Bass and the various Kontakt 5 basses, as well as with the Twin 2 (FabFilter Software Instruments) synthesizer bass presets, with the latter being particularly disturbing from the perspective of Computer Science because in great contrast to the NOTION 4 Bundled and Expansion Sounds, MachFive 3 and Kontakt 5 VSTi virtual instruments and corresponding sampled sound libraries, Twin 2 does not use sampled sound libraries, hence any "clicking and popping" in Twin 2 notes cannot be due to problems with creating or processing individual notes using sampled sounds, hence I connected a few dots; did some experiments; and discovered the solution, which one might suppose should have been obvious but at the time was not obvious, since I tend to use the "Set It and Forget It!" rule in the ongoing effort to avoid being overwhelmed by entirely too much technical computer information, where to be specific I use the term "ongoing" because in the digital music production universe everything works wonderfully when all the parameters and configurations are set correctly but does not work so wonderfully when something is incorrectly set or configured, and there are so many parameters and configurations that it can be a bit mind-boggling at times, since the operating system has parameters and configurations; all the digital music production applications have parameters and configurations; external hardware devices have parameters and configurations; and so forth and so on . . .
THOUGHTS
(1) Increasing the Audio Buffer Size for NOTION 4 running in 64-bit mode solves the problem, and with the correct Audio Buffer Size there are no "clicking and popping" noises . . .
(2) Considering (a) that the 2.8-GHz 8-core Mac Pro was state-of-the-art in 2008 (although I purchased it in 2009 when it was discounted prior to the release of the next model) and (b) that it now is mid-2013, I think that newer Macs should have a similar experience, because with the exceptions of memory busses and so forth, even the new basic iMac probably is somewhat on par with the Mac Pro here in the sound isolation studio in terms of overall speed and so forth, although when I check system performance with Activity Monitor it continues to be the case that only perhaps 20 percent of the 8-cores actually is used most of the time for digital music production, which provides a clue to the fact that the Mac Pro here in the sound isolation studio really is a supercomputer and continues to have plenty of processing power . . .
Really!
(3) There also was a problem similar to what happens with NOTION 3 when there are too many VSTi virtual instruments and the 32-bit application workspace reaches its maximum, at which time NOTION 3 begins experiencing unusual behaviors which can include freezing, and this was happening with the 64-bit version of NOTION 4 as well, but it stopped happening when I increased the Audio Buffer Size, and for reference this was happening in a NOTION 4 score that has two instances of MachFive 3, one instance of Kontakt 5 (Native Instruments), one instance of Addictive Drums (XLN Audio), one instance of Twin 2, and three NOTION 4 Bundled Instruments, which due to the extensively sampled and custom-scripted MachFive 3 and Kontakt 5 VSTi virtual instruments is doing a lot of intensive computing, even though in some respects this might appear to just a handful of instruments, where for reference the NOTION 4 Bundled Electric Guitar is doing elaborate articulations and is run through AmpliTube 3, where AmpliTube 3 is a particularly "heavy" VST effects plug-in. And since I first wrote this post I have added a few more Kontakt 5 VSTi virtual instruments, with no problems, so I am very happy with the results of increasing the NOTION 4 Audio Buffer Size to "1024 Samples" . . .
"Abyss" (The Surf Whammys ft. Pretend MIDI Daniel Erlandsson on Drums) -- Bolder Sounds Celtic Uilleann Pipes, South American Flute, and Bavarian Zither; N4 Electric Bass and Twin 2 Synthesizer Bass -- MP3 (8.3MB, 281-kbps [VBR], approximately 3 minutes and 54 seconds)
SUMMARY
Increasing the NOTION 4 Audio Buffer Size--which is done on the "Audio" tab of NOTION 4 Preferences--solves the problem of "clicking and popping" noises and also avoids causing NOTION 4 to exhibit odd behaviors . . .
In retrospect, I should have known this, but then in retrospect I should have bought a bunch of Apple and Microsoft stock in the 1980s and held it for three decades, but stuff happens and you do the best you can, and given the choice of being a really good lead guitar player or a millionaire stock investor, I am fine with being a really good lead guitar player, which is fabulous . . .
Fabulous!
