Multigigabyte sample libraries are commonplace today, delivering incredibly detailed and accurate instrument sounds. In many cases, these sample libraries are too large to fit into your computer’s random-access memory (RAM). To use these huge sampler instruments, EXS24 mkII can use a portion of your hard drive as virtual memory. When you turn on EXS24 mkII’s virtual memory, only the initial attacks of audio samples are loaded into the computer’s RAM; the rest of the sample is streamed in real time from the hard drive.
Logic Pro X automatically addresses all available system memory. The amount of RAM available for use by EXS24 mkII is determined by several factors, including:
The amount of physical RAM installed in your computer.
How much RAM other open applications and the operating system are using.
How much RAM Logic Pro X is using. This will vary in accordance with the number and size of audio files in the project, and other plug-ins used. Sampler plug-ins not made by Apple, in particular, can significantly affect the amount of RAM that Logic Pro X uses.
Virtual memory parameters
Active checkbox: Turns on the EXS24 mkII virtual memory feature.
Note: If you have enough physical RAM to hold all the samples for a project, you will see improved performance by deselecting the Active checkbox. In projects with lots of audio tracks playing and relatively few EXS instances, this may affect performance. If the Active checkbox is deselected and there is insufficient RAM to hold all samples, Logic Pro X swaps data to and from the disk, which degrades performance. Deselecting the Active checkbox also increases project load times, so you should leave it selected in most cases.
Disk Drive Speed pop-up menu: Specifies the speed of your hard drive; if you have a solid-state drive, or a 7200-rpm or faster hard drive for your audio samples, choose Fast. If you are using a 5400-rpm laptop drive for your audio samples, choose Medium. You should not need to use the Slow setting with any modern Mac.
Hard Disk Recording Activity pop-up menu: Specifies overall hard disk usage—how much recording and streaming of non-sampler-related audio is occurring. For example, if you are recording an entire drum kit using over a dozen microphones, streaming live guitars and bass, recording choirs, and so on, set your hard disk recording activity to Extensive. If your projects consist mostly of software instrument playback, with perhaps a recorded instrument or vocal or two, set your hard disk recording activity to Less. If you are unsure, choose Average.
Requires Constant RAM Allocation Of field: Shows the memory requirements of the above parameters. The slower your hard drive and the higher your hard disk recording activity, the more RAM you will need to allocate to virtual memory.
Performance section: Shows the current disk I/O traffic and the data not read from disk in time. If these numbers start rising, EXS24 mkII may glitch when trying to stream samples from disk. If you notice these values rising to high levels, change the general settings to free up additional RAM for virtual memory use. If you continue to see high Performance display values and hear audio glitches, consider installing more RAM in your Mac.
In the Parameter window, click the Options button, then choose Virtual Memory from the pop-up menu.