User manual

miniDSP Ltd, Hong Kong / www.minidsp.com / Features and speci fications subject to change wi thout pri or noti ce 38
6 GAIN STRUCTURE
When deploying a DSP solution in your audio system, a topic that becomes more important than with analog
equipment is gain structure. This means that the signal levels throughout the system should be set high enough
to maximize digital resolution and minimize noise, but not so high as to result in clipping and distortion.
The DDRC-88A provides a great deal of flexibility in matching with other equipment. In addition to providing
balanced and unbalanced inputs and outputs, input sensitivity and output gain can be selected to adapt to
different equipment. The DDRC-88A ships with a conservative gain structure that will rarely result in clipping,
but you may wish to adjust these settings for your own installation. This section explains gain structure and how
to optimize it.
6.1 GAIN STRUCTURE OVERVIEW
Figure 6.1 below illustrates the elements that affect gain and gain structure (for a single channel). The
source/processor has a master volume control and typically a user-settable trim control on each output channel.
It may also have an additional 10 dB gain on the LFE channel. The DDRC-88A has a master volume control and an
internal trim control (not visible to the user). In addition, there are per-channel settings for input sensitivity and
output gain. Finally, the power amplifier itself may have a master gain control or a level trim on each channel.
Figure 6.1. Overview of gain structure through the system