emphasize on lower frequency bands, it actually helps to suppress proximity effects and rumbling sounds caused by
wind noise. If the room turns out to develop modes and reverb in the lower frequencies, which can lead to acoustic
feedback, higher cut frequencies will be advised.
EQ:
Equalizers can be set "to taste" but shouldn't be necessary as we expect to receive a 'flat' frequency response from
any smartphone device.
Dynamics:
Compression should be applied to the Crowd Mics input to accommodate for unexpected peaks and
different microphone sensitivities. Set the compressor to a 3dB threshold at 5:1 compression ratio. Attack at 10ms and a
slow 800ms release time. Although the high compression ratio is limiting the dynamic range substantially, it will help to
create an equal volume among different talkers and smartphones, which is an important concern.
Signal routing:
It is recommended to route the Crowd Mics feed to the monitors at distinct levels, ensuring that the
presenter will intuitively listen to the audience question through the monitors. If monitor levels are set too low, the sound
perceived on stage may become unintelligible as it mixes with the FOH signal, or even with the direct sound of the
talker’s voice if seated close to the stage.
Testing:
During testing, remember that users of the participants app are supposed to speak into their mobile device's
microphone at close proximity. This will improve the signal-to-noise ratio of the spoken word, while reducing the risk of
acoustic feedback to occur. As a point of reference during setup and testing, an IPhone XS spoken into at normal voice,
6” away from the bottom microphone, the peak meter should be ranging 3dB.
Interfacing Crowd Mics with a Tesira USB input
A custom block for recommended processing on Crowd Mics is available for the processing library in Tesira Software.
Start by downloading the Catalog and Importing it to the Processing library.
Download link:
Via drag & drop, the Crowd Mics processing block can be added to any Tesira input. While USB is the preferred method
to connect Crowd Mics and Tesira, the same processing chain can be used for analog line inputs. Both versions are
available as a custom block. This example shows the setup of a USB input.
Add a USB input. In the USB Block initialization window, configure the block properties for 2-Channel "Line In/Out",
followed by "Input Channels Only":
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