QSC SC28 Speaker System Manual - Audio Inputs and Outputs Explained

Audio Inputs

On the rear panel, there are two female XLR line-level inputs marked INPUTS below the connectors and designated A and B above the connectors. Connect the line-level analog audio inputs to these connectors. Input sensitivity can be selected from the Setup Menu; selections are 1.5 Vrms/6 dBu, 3 Vrms/12 dBu, 9 Vrms/21 dBu, or 18 Vrms/ 27 dBu. These values correspond to the maximum input signal level that can be applied to the inputs without clipping. The signal's source impedance should be less than 600 ohms.

We recommend balanced connections be used. Balanced connections will reduce AC hum and interference, especially with long cable runs. Unbalanced connections may be suitable for short cables. The input impedance is 11k ohm for balanced connections or 69k ohm for unbalanced connections.

Audio Outputs

There are two sets of line-level outputs on the rear panel grouped as A OUTPUTS and B OUTPUTS. Each group has four male XLR connectors numbered 1, 2, 3, and 4. They are “mapped” with the following general convention:

OUTPUT 1- Subwoofer Output

OUTPUT 2- Low Frequency 1 Output

OUTPUT 3- Low Frequency 2 Output

OUTPUT 4- High Frequency Output

There are two Low Frequency outputs (OUTPUT 2 and OUTPUT 3) to allow for low fre- quency shading requirements of line arrays when operated in triamp mode. If the shading network of the loudspeaker is used, OUTPUT 2 is not utilized and the amplifiers are operated in biamp mode.

Input connectors

Output connectors

Pinout label on rear panel

XLR Connector Pinout

Shown are the pinouts for the XLR connectors. Male connectors shown, pinout is the same for female connectors. We recommend balanced connections be used. Balanced connections will reduce AC hum and interference, especially with long cable runs.

Unbalanced connections may be suitable for short cables. The input impedance is 11k ohm for balanced connections or 69k ohm for unbalanced connections.

Balanced connection pinout

1= shield (ground) 3= minus (-)

2= plus (+)

Unbalanced connection pinout

1= shield (ground) 3= jumper to pin 1 2= plus (+)

SC28 specifications

The QSC Audio SC28 is a powerful and versatile digital signal processor designed to enhance audio performance in various applications, ranging from live sound reinforcement to installed sound systems. Known for its exceptional audio quality and user-friendly interface, the SC28 provides a robust set of features that make it a valuable tool for audio professionals.

At the heart of the SC28 is its advanced processing power, featuring 28 total input and output channels. This includes 16 inputs and 12 outputs, allowing for flexible routing and efficient management of audio signals. Its high-performance 24-bit/96 kHz digital audio processing ensures pristine sound quality, making it suitable for even the most demanding audio environments.

One of the standout features of the SC28 is its comprehensive digital signal processing capabilities. It includes a variety of signal processing tools such as parametric EQ, dynamic range control, crossover filters, delay, and more. Each channel can be customized to meet the specific requirements of the application, empowering audio engineers to tailor the sound to their liking.

The SC28 employs QSC's proprietary Software-controlled DSP, making it easy to configure and control via a user-friendly interface. Real-time monitoring and adjustments can be made through the intuitive software, allowing for quick response times during live performances or installations. This flexibility is crucial for achieving optimal sound quality and performance, especially in challenging acoustic environments.

Moreover, the SC28 integrates seamlessly with QSC's other audio products, such as amplifiers and loudspeakers, forming a complete ecosystem for audio solutions. Its compatibility with networking protocols allows for remote control and monitoring, providing additional convenience and capabilities for sound engineers.

In terms of physical characteristics, the SC28 is designed for durability and ease of use. Its rack-mountable design ensures it fits seamlessly into any audio rig, while the robust construction makes it suitable for touring and permanent installations alike.

In summary, the QSC Audio SC28 is a feature-rich digital signal processor that provides audio professionals with the tools they need to deliver exceptional sound quality. Its advanced processing capabilities, user-friendly controls, and flexibility make it a standout choice for live sound applications and permanent installations. Whether you’re in a concert hall, a corporate event, or a large venue, the SC28 is engineered to enhance audio systems and elevate the listening experience.