Crown Audio I-Tech Series Advanced Operation, I-TechSeries Power Amplifiers, page, Delay Latency

I-Tech Series Power Amplifiers

4 Advanced Operation

control. When the memory backup is disabled, the amplifier stops storing changes made to its settings. When the next power-up occurs the amplifier uses the settings that were active when the backup feature was disabled.

CAUTION: Care should be taken to backup “safe” levels for the input attenuator controls. It is possible for the memory backup feature to be dis- abled with “unsafe” levels stored. This may result in significantly greater system gain the next time power is reapplied to the amplifier.

4.6.21 Input Signal Router

Each channel of the I-Tech’s signal processing has an Input Signal Router that allows the choice of audio signal that will be used by the channel. The user may choose one of the following configurations:

•Analog Audio: This is the audio input from the audio connector on the back panel of the amp. Choices for the Analog Audio input are Channel 1, Channel 2, or a sum of Channels 1 and 2.

•Digital Audio: This is the audio input from the AES/EBU connector on the back panel of the amp.

4.6.22 Filters

Each audio channel has five separate places where filters can be placed in the system. Up to 64 filters are available within the system. In addition to filtering, each possesses up to +/-24dB of gain. The following filters are available:

•Lowpass: Bessel 2-4, Butterworth1-4, and Linkwitz-Riley 8

•Highpass: Bessel 2-4, Butterworth1-4, and Linkwitz-Riley 8

•Lowshelf: Low-frequency shelving EQ

•Highshelf: High-frequency shelving EQ

•Lowpass EQ: Variable Q from 0.1 to 35

•Highpass EQ: Variable Q from 0.1 to 35

•Parametric EQ: Variable Q from 0.1 to 35

•All Pass: 1st and 2nd order

All Pass filters provide no gain change to the output, but provide a phase change at the selected frequency. This corrects the phase relationship of the output without a gain reduction, such as is found in other filters.

4.6.23 Delay (Latency)

Due to the nature of DSP processing, there is some inherent delay or latency within the I-Tech’s DSP. These delays are:

•1.13mS analog

•2.36mS digital (44.1 kHz)

4.6.24 Noise Generator

Each channel has an independent uncorrected noise generator that allows noise to be mixed into the audio signal. This is useful for noise masking applications and testing. Each channel has the following controls:

•Noise On/Off: The channel’s noise generator can be independently turned on.

•Noise Type: Full spectrum white noise or pink noise.

•Noise Level: A fader to allow the noise level to be controlled.

4.6.25 Sine-wave Generator

A sine-wave signal generator allows the mixing of a single tone into the audio signal. Typical applications can be for the injection of a high fre- quency tone (19kHz) into the signal in paging type system to continually drive the speaker, allowing continuous monitoring of the speaker load. The following controls exist:

•Sine On/Off: The sine-wave signal generator’s function.

•Sine Frequency: Controllable from 20Hz to 20kHz.

•Sine Level: Each channel’s sine-wave signal level can be indepen- dently controlled.

Operation Manual page 27