Do you see why a larger sample buffer is less taxing on the CPU? Imagine these two systems processing audio over a period of 5 minutes. Since it takes more time to fill up the 1024 sample buffer, the CPU will have to do less work over the same period of time. Thus, the time it takes for the buffer to fill up can be defined as
latency. Sample Rate
Contrary to popular belief, increasing your system’s sample rate will actually reduce your latency. Latency can be calculated by dividing buffer size by sample rate. Provided we use a consistent buffer size of 128 samples, the following can be calculated.
44.1 KHz (44,100 Hz) 128⁄ 44,100 ~ 2.9 ms of latency 96 KHz (96,000 Hz) 128⁄ 96,000 ~ 1.33 ms of latency
With this in mind, why wouldn’t you want to increase the sampling rate to something obscene like 192 KHz or 384 KHz?
Remember when we said the audio buffer is filled at a fixed rate? That rate happens to be your system’s sampling rate. Thus, an increase in sampling rate will fill up the audio buffer faster, resulting in more CPU usage.
Standalone vs. Host
Some VST plugins like Native Instruments Kontakt and UVI Workstation can be used in standalone mode. Others like Spectrasonics Omnisphere and Keyscape can only be used inside a DAW or host software like Ableton Live or Apple MainStage.
If your set only uses a few Kontakt libraries without complex programming in a host software like MainStage, just use the standalone version of Kontakt. Likewise, if you’re only going to be playing on a grand piano sound, just load up Ravenscroft 275 in the standalone UVI Workstation.
Some VSTs have standalone apps. Use those whenever possible.Using a VST in standalone mode eliminates the extra latency and resource overhead of a host program. Mechanical Hard Drive vs. SSD
While the speed of your hard drive doesn’t directly affect latency, it can definitely have an effect on overall system performance. If you hear audio glitches while playing back large sample libraries, increasing the buffer size (thus increasing latency) may not be the best way to fix the problem.
As you can see, the relationship between audio driver, buffer size, and sample rate is important (and fragile). Here’s what I recommend.
First, get a decent audio interface with optimized drivers. Once again, there’s no need to drop $2,000 on RME gear. Zoom’s UAC-2 and UAC-8 perform just as well in the latency department. Stick with 44.1 KHz or 48 KHz. These sample rates offer the best compromise between sound quality and system performance. Reduce the buffer size until you start hearing audio clicks and pops, then increase it one notch. For example, if you start hearing glitches at 128 samples, try set it to 256 samples instead.