The Soundcraft Si Expression 2 Digital Mixer is a digital mixing console designed for live sound applications. The mixer features 24 microphone preamps, 4 line inputs, AES in, 4 internal stereo FX returns, 22 faders, a 64 x 64 expansion slot for additional routing possibilities, and 66 input processing channels.

Every input processing channel on the board can be routed through a dedicated high-pass filter, input delay, compressor, gate, and four-band equalizer. Each channel is also under the control of an automation system with four mute groups and illuminated faders to keep track of signal processing. For outputs, the mixer includes 16 balanced line outputs, a headphone monitor output, AES output, and the 64 x 64 expansion slot.

The mixer features 14 aux/group mixes that can be used as 14 mono mixes, or 8 mono and 6 stereo mixes, or any combination between. The mixer also utilizes 4 matrix mixes that allow you to assign any combination of inputs to any combination of outputs in either mono or stereo mode. In addition to the auxiliary/group and matrix busses, the unit features four mix busses dedicated to the device's internal Lexicon FX processing. Each bus mix includes a delay, compressor, a four-band equalizer, and a BSS graphic equalizer. Since the Lexicon FX processor is hardware based, using the effects does not influence the signal processing performance of the rest of the mixer.

For I/O expansion, the mixer will accept any of the Soundcraft Si series option cards including AES, AVIOM, CobraNet, Firewire/USB/ADAT, Dante CAT5, and optical MADI. The MADI card allows you to connect to multi-track recording systems, plug-ins such as WAVES, and Studer or Soundcraft stageboxes. Using a stagebox increases both the number of physical inputs, as well as the number of input processing channels. Every processing parameter utilizes a dedicated control so that you do not need to navigate through menu hierarchies to make adjustments. A row of global mode encoders above each channel gives you control over gain, high-pass filter parameters, and pan position.

Multi-Color Illuminating Faders

The faders on the mixer glow different colors to indicate the status of the auxiliary sends, graphic equalizers, and FX sends

Equalizer

The equalizer section of the mixer features high shelf, low shelf, variable Q ranging from 22 to 20,000 Hz

Color Touch Screen

The mixer features a color touch screen for setting up monitoring, labeling, and assigning inserts and patch channels

66 Mix Channels

The mixer offers 66 inputs to mix, all with dynamics, EQ, and routing

ViSi Remote Control

The mixer works with the ViSi remote control app for iPad. This allows you to remotely control the mixer from anywhere in the room over the iPad. Multiple iPads may be used to control different sections of the mixer. To operate the mixer remotely with an iPad, first connect a wireless router to the mixer's Harman HiQnet Ethernet port. The iPad connects to the mixer via Harman's HiQnet network. To create the Harman HiQnet network, you connect a wireless router to the mixer's Harman HiQnet Ethernet port

TOTEM One Touch Easy Mix System

The mixer features a one touch easy mix button that instantly reconfigures the surface and faders of the mixer so that you can mix to an FX, auxiliary, or matrix bus

Assignable Channel Strip

The mixer allows you to select channels and then use the assignable channel strip to adjust input-signal gain, gate, compression, equalization, panning, and output-signal gain. Each rotary knob in the assignable channel strip is correlated to a dedicated function, just as it would be in an analog mixer

35 Busses

For sub-mixes and flexible routing options, the mixer features 35 busses

Global Mode Encoders

A row of rotary encoders at the top of the mixer allow you to always access the gain, pan, and filter controls over any channel on the mixer

Direct Output Gain Stabilization (D.O.G.S.)

When two consoles are sharing the same source, the D.O.G.S. system maintains the same gain structure of microphone in to direct out on both consoles. This is useful when utilizing the mixer to send stage mixes to musicians wearing in-ear monitoring systems. No matter how the levels might be changed on the mixer, the D.O.G.S system will ensure that the direct output level to the musicians remains constant

Lexicon FX Engine

The mixer features four hardware-based Lexicon FX engines, each on its own FX bus. This allows you to perform complex FX signal processing on any channel without running out of system resources. The Lexicon FX engine features over 20 preset stereo effects, accessible via the rotary encoders and touch screen

Graphic EQ

The mixer includes a 28-band graphic equalizer on every matrix, mix, and, main master

Copy and Paste

The copy and paste function allows you to copy all or any part of a channel, mix, buss, or Lexicon effect such as a gate, compressor, or EQ and then paste it onto another part of the mixer

Function Focus

Every time a control is changed or the select key is pressed, the screen will display relevant information about the channel being changed and the absolute values of the controls over that channel

Instant Access Keys

On the front of the mixer is a panel of buttons such as STORE, RECALL, NEXT, MUTE 1-4, TAP TEMPO, and others that provide instant access to basic functions without having to navigate complex menus

USB Setting Storage

The front of the mixer features a USB port that allows you to save mixer settings to a USB memory stick for future use

Security Lockout

You can lockout parts or all of the console with separate user profiles and permissions