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The standard instrument input with high impedance and low noise.
The high-impedance ALTERNATIVE INPUT is located on the back panel. You may find it useful in rack setups, either for connecting the instrument directly, or through a wireless receiver. It is a bit noisier than the front INPUT, but this is only an issue for guitars with a soft output level, applied to heavy distortion. Even when Input Source is set to “Alternative Input”, it won’t work when a cable is still connected to the front INPUT. You can still use Loop Mono when using the ALTERNATIVE INPUT but avoid using Loop Stereo; it uses the ALTERNATIVE INPUT as the right return input for the loop, and the PROFILER does not automatically compensate for this situation.