The concept of computer farms is rather simple : “a collection of computers networked together to accomplish performance needs far beyond the capability of one machine”. This is, in many ways, not a new concept in the world of composer’s studios ; back to the days of hardware samplers, it was quite often necessary to buy more than one sampler to load more samples and get more polyphony.
Take for example a typical GigaStudio setup, in which the whole idea is to unload the sequencer from the task of processing the samples. As a result, and for performance and memory reasons, loading a full orchestra, with a certain number of articulations per instrument, usually requires to install two or three GigaStudio computers.
In the world of Apple computers, this concept has rarely been applied because, for many years and until the PowerMac Quad and the recent Intel Macs came out, the performance/cost ratio was most of the time in favor of their PC counterparts. Yes, there have been, and for some time now, very good examples of server farms made solely of Apple Xserves, but this was far beyond the scope of a modest composer’s studio.
A dedicated Apple user, John Frizzell (Alien Resurrection, Gods & Generals…) has been looking in this direction for a long time. As many composers, John found himself forced to use GigaStudio – even though he didn’t like using Windows. So he finally designed a system of three PowerMac G5, one host (the sequencer) and two slaves. On the host, he runs Logic, Rax, and Plogue Bidule. Each software allows him to load up to about 2.5GB of samples. Then, on each slaves, he loads another 2.5GB of samples in Rax. Memory and performances being the main limitation on today’s computers, this allows him to have all his samples always loaded in the background, like in a typical GigaStudio setup, but without ever using Windows (which, for some users, is not a small benefit).
Using PowerMacs to spread your samples is a great idea, but it has its downsides too. PowerMacs are bulky, take a lot of space, generate a lot of heat, and use up to 400W (this is not going to help your electricity bill!). They are also expensive, and require a rather complicated setup if you are using more than one host.
Here is another problem, this one specifically related to how Vienna Instruments handles memory. We already know that a 32-bit application can only use up to 2.5 GB of ram. This means that you can load up to 2.5GB of samples in Logic, 2.5GB of samples in Rax, 2.5GB of samples in Plogue Bidule (remember that this is a theoretical limit – in the real world, most apps hardly reach it). Basically, this allows you to have a PowerMac with 8GB of memory running three hosts.
But the Vienna Instruments loads its samples in a separate application, called “VSL Server”. You do not see this application – it simply runs in the background. Because it is a process separated from the host, it can go higher than the usual 2.5GB limit, up to 3.25GB (some users have reported going even higher than that.) However, if you are running two or three hosts on your computer, you will not be able to load more than a total of 3GB of VI samples on this computer, because they will point to the VSL Server process. Suddenly, the PowerMac is way less interesting – why bother buying such an expensive and powerful computer, to only use less than half of its capacities?
Well, that’s where the Mac Mini comes in. In terms of raw power, the new Intel Mac Minis are as powerful as a PowerMac Dual 2 Ghz (this is not too surprising, considering the fact that the processor inside the Minis, the Intel Core Duo, is also a dual-core processor, and runs at 1.6 or 1.8 Ghz), and they are also way smaller, generate little heat, and consume only 80W. You can load up to 2GB of memory on each of these little babies. And they come with optical S/PDIF (2-channel) I/O connectors.
They do come with one downside though : the internal, SATA hard drive only runs at 4200rpm. This can be a problem when working with samples, so it is highly recommended to add in a faster, external firewire drive, or to pop the Mac Mini open and replace its internal drive by a faster one. Firewire drive are IDE, not SATA, so the second solution is even better (however, since you open up the computer, you will lose the manufacturer’s warranty).
A Mac Mini will handle up to about 1.6 GB of VI samples loaded in memory (the rest is dedicated to running the OS and other regular tasks). As a comparison, a PowerMac or a Mac Pro with 4 GB of memory will allow you to load about 3 GB of samples. So, four Mac Mini will do the task of two PowerMacs / Mac Pros. Money wise, this comes down to $4000 for four 2GB, 1.8 Ghz Mac Minis (along with an external Firewire drive) against $6400 for the two 4GB, 2 Ghz Mac Pros. Nice savings, to be added to the other positive factors of buying a Mac Mini (space, heat, power consumption).
The cool thing with this solution is that you can buy Mac Mini’s at your own pace, as you would for the VI collections. For example, if you only have Strings I and Strings II, and you want to use all of the Level 1 articulations, then you won’t need more than two Mac Minis. If you later buy the Woodwinds I collection, then you can buy another Mac Mini and load it up.
Ultimately, if you want to use the full power of the Symphonic Cube package, you will probably need about 10 Mac Minis – one for each collection. But this will still be way cheaper than buying PowerMacs or Mac Pros.
Keep in mind that the whole concept of computer farms applied to the composer’s studio is only useful if you want to have your samples loaded at all time. It does not help you if you are more likely to load your instruments / samples on a project basis.
In later articles, I will talk more in depth about setting up your sequencer and MIDI gear to interact with the VI interface, spreading your samples over the whole Mac Mini farm, and the different options to get the sound out from your slaves, back to your host.
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