Latency

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Description

Latency describes the time passed between the moment an audio signal enters some device and the moment when it leaves the device. Especially in the digital audio world we might have AD converters, some digital signal processing (DSP) and DA conversion involved. All this processing takes time. How much time does the Kemper Profiler take? What's the Profiler's latency and can we change or adjust it?


Profiler & Latency

The Kemper Profiler has a variable latency by default. The effective latency depends on the type and amount of effects used in a specific rig. The latency can even change when you change parameters of an effect like Transpose. Although the default latency is variable, you can expect it to be around 3ms. The fact that you can't exactly tell the latency in this variable mode has an impact on especially 2 situations:

  1. Reamping and mixing the profiler more than once by using the same guitar track for reamping. That is the situation showed by some of you.
  2. Playing two or more Profilers at the same time by splitting the guitar signal and feeding both/all Profilers with it.

To provide a solution for the 2 situations describes above, Kemper decided to provide a hidden setting starting with firmware 1.6.0 public beta to make the latency a little higher but constant. This constant latency would be 4.9ms. In current firmware this switch isn't hidden anymore.

To switch to constant latency and back, go to OUTPUT/MASTER menu -> Page 5/5 and press soft butten 4, wich is the 4th button above the display of your Profiler. The button has no label. If the button is not lit, the latency is variable. If the button is lit, the Profiler's latency is constant.[1]

References

  1. Christoph Kemper describes the variable & constant latency, January 13th 2013