14
Amp Output Component
The Amp Output component in QDS can have one to four inputs/outputs depending on the amplifier model and its configuration
in QDS. The desired configuration is selected in the QDS Properties menu for the amplifier. When the amplifier's configuration is
changed, all of the outputs are placed in a "mute all" state. You can un-mute all by clicking the Mute All button in the QDS Amp Output
component.
Amplifier Sensitivity
Amplifier sensitivity is set to provide full output voltage swing for the rated power (@8 Ohms), with a 0dBFS PEAK input. This means that
MAX DAC Out = MAX AMP Out, with a SINE WAVE (0dBFS = -3dBFS RMS for a sine wave).
For 70V/100Vrms systems, there are gain adjustments required that occur in the Hi-Z speaker block (70/100V Speaker component in
QDS). In addition, there is a High Pass Filter (HPF) that is automatically applied at 50Hz to avoid transformer saturation.
Limiters
There are several limiters within the SPA-Qf output:
• Speaker Component Limiters – These have controls exposed to the end user. Refer to the diagram on page 13. Speaker-related
limiters are not indicated within the Amp Output block or front panel.
• Amp Protection Limiters – These are not adjustable and are meant only to protect the amplifier from unsafe conditions. Amp
protection limiters are slow-moving that adjust over longer periods of time. Indicators for this limiter can be found on the individual
amplifier channel or the front of the amplifier.
• DAC Limiters – These limiters engage approximately 1dB before clipping. It is normal to have some level of DAC clipping during
operation. There are no controls over this limiter.
Mutes
• Channel Output Mutes are located within each channel strip of the Amp Output component control panel. Activating this button will
turn off the output signal of the DAC.
• Mute All function, found at the top of the Amp Output control panel, will turn off the amplifier switching for all channels.
Gain
There are multiple places within Q-SYS to add gain to your system. Within the amplifier, it is critical to understand that the gain within
the Speaker component should typically not be above +10dB. This is due to the dynamic nature of music and the stress that this can put
on the output of the amplifier. Speaker component gain above +10dB could trigger the Amp Protection Limiters or DAC Limiters.
