Extron electronic MLS 406SA, MLS 304SA, MLS 304MA manual Unbalanced Mono Output Balanced Mono Output

PRELIMINARY

Installation, cont’d

•The Preamp connector outputs a variable, line level audio signal for use with a powered amplifier or self-powered speakers. The volume can be controlled (attenuated) via the front panel knob or RS-232 communication. The volume range is 0 (mute) through 100.

Lineout and Preamp outputs can be set up as

•unbalanced, -10 dBV (-7.8 dBu, 0.316 Vrms, default) for consumer level devices such as VCRs, DVD players, and stereo receivers

or

•balanced, +4 dBu (+1.8 dBV, 1.228 Vrms) for professional devices such as mixers, signal processors, and power amps

depending on how the connector is wired and how the MLS is set up (via the control software). See the following wiring diagrams and chapter 4, Serial Communication.

Tip	L	Left	Tip	L	Left
NO GROUND HERE.			Ring
Sleeve(s)			Sleeve(s)
Tip	R	Right	Tip	R	Right
NO GROUND HERE.			Ring

Unbalanced Stereo OutputBalanced Stereo Output

CAUTION

For unbalanced audio, connect the sleeve(s) to the center contact ground. DO NOT connect the sleeve(s) to the negative (-) contacts.

Tip	L	Left	Tip	L	Left
NO GROUND HERE.			Ring
Sleeve		Right	Sleeve		Right
	R			R
Unbalanced Mono Output			Balanced Mono Output

CConnect the sleeve to ground (Gnd). Connecting the sleeve to a negative (-) terminal will damage the audio output circuits.

NFor mono output, wire either the left or the right side, not both.

CDo not bridge mono outputs. The left and right input signals are summed, and each mono output channel carries the same combination signal.

NIf the output is wired for balanced output, the level is +6 dB higher than the level for unbalanced output wiring. The balanced/unbalanced level difference occurs no matter which line level output setting is chosen via RS‑232. See page 4-10.

NAfter the audio inputs and outputs are connected, see chapter 3, Operation and Setup for instructions on how to adjust the per-input audio sensitivity levels and optimize Lineout and Preamp output.

NIf the Loudness feature is turned on, the gains for bass and treble frequencies are affected for all outputs whenever volume is adjusted.

Amplified output (MLS 304MA, MLS 406MA only) — Cable speakers to this 5-position screw terminal for a mono amplified audio output. This provides a mono output signal even if the input is a stereo signal. For stereo output, use the non-amplified Lineout and Preamp outputs instead.

The 4 ohm/8 ohm direct connection circuit and the 70 V/100 V transformer connection are mutually exclusive: only one circuit (direct or transformer) can be active at a time.

CDo not short the terminals to ground or the amplifier will be damaged.

CDo not bridge mono outputs. Bridging could damage the amplifier.

2-10 MLS 304 Series, MLS 406 Series • Installation