Extron electronics DMP 128 - Page 48

Meters
• ERL – the ratio in dB between the signal at the reference and the signal at the AEC
channel input. When ERL is a positive number, the signal level at the AEC channel
input is lower than the signal at the selected reference (0 to +15dB is desirable).
• ERLE – the amount in dB of potential echo signal that the AEC algorithm, not
including NLP processing, is cancelling.
• TER – the sum of ERL + ERLE, in dB.
Select Reference
Select the AEC reference from a drop-down list, populated with
the following:
• Output channels (1 – 8)
• Input channels (1 – 12)
• Virtual Return channels (A – H)
Noise Cancellation
Noise cancellation can be switched on or off from the AEC dialog.
The noise canceller detects steady state noise, such as HVAC or
other continuous system noise, and effectively remove it without
causing audible artifacts.
Noise cancellation is engaged or disengaged using a checkbox.
When the box is checked, noise cancellation is engaged, or
switched on. When cleared, noise cancellation is disengaged, or
switched off. The default setting is noise cancellation switched on
and set to 15dB of noise attenuation.
Up to 20dB of noise cancellation is available, in 0.1dB
increments.
Setting Gain Structure for AEC
It is important to optimize the audio levels of the DMP128 for AEC to be effective (see
Optimizing Audio Levels on page100).
DMP128 • Software Control 42