•When connecting an unbalanced output to a balanced input, be sure that the signal high (hot) connections are wired to each other. The unbalanced ground (earth) connec- tion should be wired to the low and the ground connections of the balanced input. If there are ground-loop problems, try connecting the un- balanced ground connection only to the input low connection, and leaving the input ground connection disconnected.

•In some cases, you will have to make up special adapters to interconnect your equip- ment. For example, you may need a balanced XLR female connected to an unbalanced 1⁄4" TS phone plug. The balanced-to-unbalanced connection has been anticipated in the wiring of Mackie jacks. A 1⁄4" TS plug inserted into a 1⁄4" TRS balanced input, for example, auto- matically unbalances the input and makes all the right connections. Conversely, a 1⁄4" TRS plug inserted into a 1⁄4" unbalanced input automatically ties the ring (low or cold) to ground (earth).

BINDING POSTS

The binding posts provide a safe and secure connection for speaker wire.

Prepare your wire by stripping back the insulation to reveal clean, shiny wire. Make sure it is not stripped back any further than 3/8” (9.5mm), to avoid the chance of a shock haz- ard. Carefully twist the wire so that any fine wire strands are together.

Make sure the amplifier is turned off before connecting the speaker wire, as there may be high AC voltages present at the outputs

•Untighten the posts and insert the bare wire as shown below.

•Check there are no strands of wire sticking out which may touch the other terminal.

•Tighten the posts by hand, do not use a wrench!

SPEAKONS

Speakon® connectors have become popular with many loudspeaker manufacturers because they provide a quick, yet safe and secure method of connecting speaker cables. The connectors have a twist-locking mechanism that prevents them from being pulled out acciden- tally. Plus, they are capable of handling high currents and meet IEC 65 and IEC 348 safety requirements.

Pin 1+ is speaker positive(+) and Pin 1– is the speaker negative (–).

The amplifier is fitted with three Speakon connectors, one for the left, one for the right and one for the bridged mono operation. The bridged mono connector must not be used with any other connection, no speaker wire attached to the binding posts, and no other Speakons used.

Internally, the bridged mono Speakon is wired directly to the binding posts. Pin 1+ is connected to the Channel 1 positive and Pin 1– is connected to Channel 2 positive. If you find that your speaker (in bridged mono) sounds strange, check that the AMP MODE switch is correctly set to BRIDGED. Otherwise, your speaker will be playing the difference between Channel 1 and Channel 2, like an earlier method of home theater center fill.

 

 

 

1+

1–

1+

1–

2–

 

 

 

2+

 

COLD

 

HOT

Figure E: Speakon

Connectors

Figure D: Binding Posts with Bare Wire

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