Crown SMX-6 Brochure

@crown

* System® Product Reference

SMX-6™ Automatic Mixer

ENABLEDSPI

120 VAC

60 Hz

20 W

AUX CTRL

RS232 / RS422

CROWN BUS

SERIAL DATA LOOP

OUT IN

+–+

INPUT

GROUND

ONLY

–

(Front Panel shown above, Rear Panel shown below)

OVERVIEW

What is an SMX-6?

The SMX-6 is a single rack space six by two automatic mixer designed to be configured with a computer and appropriate software. Once initially setup the computer becomes optional. The key to the ability of the SMX-6 operating as a stand alone automatic mixer is distributed intelligence™. In an IQ System the brains of the system live out in the system. This means the audio system is not going to be lost even if the computer or communication cables fail. Due to the modular nature of the SMX-6, multiple units also may be used together to form a wider or deeper automated mixer.

HARDWARE BLOCK DIAGRAM

Refer to the pictures of the front and rear panels shown above and the block diagram of the SMX-6 mixer on Page 2.

Audio Main Inputs:

Six balanced inputs with removable 3 pin barrier block. The preamp stage includes:

• M/L/P switches set each input to line level (L) with 0 dB gain, mic level (M) with 25 dB additional gain, or phantom (P) which is 25 dB additional gain and +44 VDC phantom power.

• A trim pot at each input allows for prefade gain adjustment of –12 dB to +21 dB gain after the M/L/P

switch. Prefade sensors at the output of each preamp stage sense input audio level just before the input signal is delivered to the processor controlled VCAs. There are two VCAs under processor control

AUDIO IN

-5

-10

-12

+–

ADD 25 FOR MIC

10 15

LMP

AUDIO OUT

MAIN

STACK IN

BUS

AUDIO OUT

MAIN BUS

STACK IN

AUDIO IN

+–+–+–+–+–

AUDIO

ADD 25

FOR MIC

-5

-10

-12

LMP

ADD 25

FOR MIC

-5

-10

-12

+– +– +– +– +–

SMX-6 SENSING MIXER

at the output of each sensor. One VCA controls the gain from input to output mix 1 and the other VCA controls gain from the input to output mix 2. The net result is 12 VCAs total, six per output mix.

Audio Stack Inputs:

Two inputs, one per output mix. Connections are via unbalanced RCA phono jacks. These inputs are op-amp isolated. There is no processor control of audio coming into these inputs. The purpose of the stack inputs is to allow construction of a wide mixer with more than six inputs by taking the outputs of one mixer and going into the stack inputs of a second mixer. This means that main inputs do not have to be used to expand the effective size of the overall mixer.

Audio Main Outputs:

There are two summing buses. Each summing bus provides the out-

AUDIO OUT

MAIN BUS

put mix for the corresponding output channel. Op-amps buffer the summing bus to the output connection and balance the audio output. The outputs are via 3 pin removable barrier blocks.

Audio Bus Outputs:

In addition to the two main outputs, there are also two bus outputs. Bus outputs 1 and 2 provide the same audio output as main outputs 1 and 2. Op-amps buffer the summing bus to the output connection and balance the audio output. What makes the Bus Outputs different are relays under processor control which may be used to turn on or off the Bus Output drive. 3 Pin removable barrier blocks are used.

Aux Port:

The unit is equipped with a TB-3M type

Page 1 of 5

LMP

STACK IN

+–+–

AUDIO IN

-5

-10

-12

AUDIO

ADD 25

FOR MIC

-5

-10

-12

LMP

AUDIO

ADD 25

FOR MIC

-5

-10

-12

LMP

AUDIO

ADD 25

FOR MIC

10 15

LMP

mini-XLR port. This port may be used to provide a control signal or sense a control signal.

• Pin 1 is ground reference

• Pin 2 is output under processor control. When on it provides 10 VDC at 16 ma. When off it is open collector (high impedance).

• Pin 3 is sensing input. +5 to +30 VDC is sensed as a logic high. The circuit floats, therefor tie to ground or TTL source for definite high or low.

Indicators:

A Power light on the front panel indicates the unit is plugged into AC mains and AC power is available. A DSPI data signal presence indicator lights to indicate communication or may be forced on via processor control.

Crown Bus Port:

The Crown Bus is a serial data loop where components are connected into the loop and one component serves as system interface for all. This unit may serve as a system interface or may simply operate as a component on a Crown Bus data loop. Although the Crown Bus may function on a variety of media, Crown uses a two-wire 20 ma current loop for input and output Crown Bus connections. On this unit connections are made via 4 pin removable barrier block. Even if the unit is communicating directly with a PC via its serial port, it always functions in software as an addressable component on a Crown Bus loop. The unit must have a valid loop address. A valid address is:

• 1 to 250 set via 8 segment DIP switch

• No other SMX on the same Crown Bus data loop may have the same address.

ADD 25

FOR MIC

-5

-10

-12

LMP

@crown

* System® Product Reference

INPUT 1

BALANCED BUCHANAN

CONNECTOR

INPUT 2

BALANCED BUCHANAN

CONNECTOR

INPUT 3

BALANCED BUCHANAN

CONNECTOR

INPUT 4

BALANCED BUCHANAN

CONNECTOR

INPUT 5

BALANCED BUCHANAN

CONNECTOR

INPUT 6

BALANCED BUCHANAN

CONNECTOR

STACK INPUT 1

M/L/P SWITCH

PRE-AMP

GAIN POT

(-12 to +21dB)

M/L/P SWITCH

PRE-AMP

GAIN POT

(-12 to +21dB)

M/L/P SWITCH

PRE-AMP

GAIN POT

(-12 to +21dB)

M/L/P SWITCH

PRE-AMP

GAIN POT

(-12 to +21dB)

M/L/P SWITCH

PRE-AMP

GAIN POT

(-12 to +21dB)

M/L/P SWITCH

PRE-AMP

GAIN POT

(-12 to +21dB)