MACKIE SPIKE
Owner's Manual

There are many factors that contribute to latency, and there is one in particular that you can control: the software audio buffer size. The audio buffer (also referred to as ASIO buffer on a PC, or Core Audio buffer on a Mac) is an area in memory that Tracktion uses to hold your audio as it works. The buffer size is measured in samples, and usually ranges from just a few samples to thousands. The smaller the buffer, the faster the audio gets in and out of your computer, and the lower the latency. We would like to set this buffer as low as possible to achieve the lowest latency, but there is another factor to consider: The smaller the buffer, the harder your computer will have to work. To illustrate this, pretend you are given �ve minutes to move water from a large bucket to another bucket ten feet away. You must use either a large pint glass or a small whiskey glass to transfer the water. Which would you chose? The pint glass of course. If you choose the whiskey glass, you would quickly grow tired of running back and fourth moving the small amount of water. Depending on your �tness and speed, you may not be able to move it all in �ve minutes. This is similar to how your computer deals with the audio buffer. If you choose too small a buffer, the computer needs to work very hard to quickly transfer the audio in and out of the buffer. It may not even be able to keep up, especially if you have lots of tracks, lots of automation and/or lots of plug-ins in your work. If this happens, your audio may stop or �drop out.� Drop outs at low buffer sizes may also occur if you have a slower computer or not enough memory. For low latency and good performance from your system, it is best to adjust the buffer size to taste. You often need to use trial and error to �nd an acceptable buffer size. In Tracktion, this is done by choosing the Settings tab, choosing the XD-2 in the Wave Device drop down menu, and adjusting the Latency. Usually, a setting less than 256 samples will yield �ne results, while a setting of 128 samples or less will be required for almost inaudible latency. Note: While you are recording, low latency is often a priority. Mixing existing tracks on the other hand, does not often need such extremely small settings. Many users adjust their buffer setting between the tracking and mixing stage. Increasing the buffer size while mixing may allow you to run a few extra plug-ins; try 1024 or 2048 samples. User�s Guide

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