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User interface and controls

Live IO controls.

Name

Allows to define a custom name for each channel. This is a global name; saved and restored with the preset but not directly related to the Hardware I/O Interface. As this, it will be consistent even if you switch the Hardware I/O Interface or switch to connect to a SampleGrabber.

Ref

The button toggles whether the corresponding channel should be used as a reference signal.

Multiple channels can be used as reference, in which case a mono-sum of these channels is used as the internal reference signal.

Mic

The button toggles whether the corresponding channel should be used as a microphone input signal, which is used to capture the response of the system.

Multiple channels can be used as microphone input, in which case a mono-sum of these channels is used as the internal microphone signal.

Phase invert

The toggles phase inversion of the selected channel on and off. This can be used to compensate another known phase inversion somewhere else in the analog signal chain.

On/Off

The button toggles delay compensation on and off. When the correct delay has been determined, engage this button to insert a delay line in the reference channel, to align reference and measured signals, and get correct transfer function and impulse response.

On/Off delay button appears only on channels toggled as microphone>

Delay value

The delay value is displayed simultaneously as:

You can manually adjust any of these values, using either keyboard input or fine increments with the up and down arrows; the two other values will change accordingly.

Please note precision of the distance value depends on correctness of the temperature value inserted in the main setup. In a concert hall with an audience present, there will probably important temperature variations, so this value should only be seen as a rough measure.

Lastly, remember the delay value in samples is the master value, from which others are derived.

Delay values appears only on channels toggled as microphone>

Find

Clicking the button starts a new delay value computation. Previous values, whether computed using the delay finder or entered by hand, will be erased. The algorithm accumulates a certain amount of incoming signal before the actual computation is actually performed, to ensure the delay is always computed using the most current audio.

Find Delay appears only on channels toggled as microphone>

Progress

An informational text showing the progress of the computation is shown when the delay find button is clicked, as well any error potentially encountered.