This document is an instruction manual for Mission Loudspeakers, providing comprehensive guidance on their setup, connection, positioning, maintenance, and technical aspects.

Function Description

Mission Loudspeakers are precision-manufactured audio products designed to reproduce music with exceptional realism and high fidelity. They are engineered using advanced computer-controlled technology to deliver a smooth, accurate, and balanced sound across the audio frequency band. The loudspeakers are designed to be an integral part of a hi-fi system, transforming electrical energy into mechanical energy to create a three-dimensional stereo sound stage with correct instrument size and position. They are optimized for wide dynamic range musical reproduction, preserving power response linearity throughout the dynamic range and allowing the reproduction of large transients while maintaining quality at the lowest levels. The design also focuses on minimizing coloration, which refers to various distortions and aberrations that can occur in loudspeakers, including both 'additive' and 'subtractive' distortions. The drive units are 'Direct Coupled' to substantial baffle boards made of special materials, and the enclosures are precision-designed and visco-elastically damped to reduce unwanted acoustic output and eliminate internal standing waves. The driver membranes are made of special, rigid, and acoustically opaque materials with optimized mathematical profiles and mechanical terminations, ensuring smooth performance with controlled break-up modes and minimal resonances.

Usage Features

Running-In Period: For optimum performance, the loudspeakers should be run in for a period of 10 hours before final positioning. This allows the sophisticated drive units to settle and achieve their best sound quality.

Connecting Your Loudspeakers:

Conventional Wiring (Fig. 3): For loudspeakers with two or four connection terminals, a single two-core cable per loudspeaker is used. If your loudspeaker has four terminals, ensure the two shorting links supplied are installed. To do this, remove the HF terminal caps, loosen the LF caps, place the wire link through the vertical hole in the LF terminal, slide it up through the HF terminal, replace the HF cap, centralize the link, and tighten both LF and HF caps for a firm contact. Connect the red positive (+) terminal of your right-hand loudspeaker to the red or positive (+) terminal on the right channel of your amplifier. Connect the black negative (-) terminal of the same loudspeaker to the corresponding black or negative (-) terminal of your amplifier. Repeat for the other channel to ensure phase correctness.
Bi-Wiring (Fig. 4): This scheme uses four conductors, one for each terminal, to enhance performance by eliminating signal distortion caused by low and high-frequency currents interacting within a single cable. Remove the shorting links from each of the Red and Black terminal pairs on the rear of your loudspeakers. Use two lengths of two-core loudspeaker cable per loudspeaker. Connect the system as shown in Fig. 4, ensuring correct polarity. If your amplifier has only a single set of connectors, the two wires will need to be joined at the amplifier connector.
Bi-Amping (Fig. 5): This further enhances performance by using separate amplification for the low and high-frequency sections, eliminating distortion from current interaction in the amplification stage and loudspeaker cables. This requires four amplification channels (four power amplifiers or two stereo amplifiers in mono mode). Remove the shorting links from each terminal pair. Use two lengths of two-core loudspeaker cable and one stereo amplifier (in mono mode) per loudspeaker. Connect as per Fig. 5, ensuring correct polarity. Using identical amplifier units is recommended to avoid imbalances.

Positioning Your Loudspeakers (Fig. 1 & 2):

Loudspeakers are designed to be placed directly on the floor (ideally using spikes) or on Mission Stands, depending on the model.
Position them approximately 20 cm (8 inches) away from the back wall and 1.8 meters (6 feet) apart, with their fronts facing straight out.
The distance from either loudspeaker to the side wall should be a minimum of 0.5 meters (1.5 feet).
Vary the distance between the two loudspeakers from 1.5 to 2.5 meters (5 to 8 feet) to achieve a perfect stereo stage.
Adjusting the distance from the back wall affects the virtual image and enhances bass extension.
The loudspeakers are designed for a smooth 'off-axis' frequency response, meaning they should not be 'toed in' or angled towards the listener. Position them with their backs parallel to a rigid back wall.
Avoid positioning loudspeakers against bay windows, French windows, loose partitioning, or in room corners.
The hi-fi system should be positioned well away from the loudspeakers on a rigid and light stand or cabinet.
A few minutes spent adjusting the position will result in a breathtaking three-dimensional stereo stage.

Use of Spikes: Floorstanding models are supplied with stabilising spikes for better coupling to the floor. Turn the loudspeaker upside down on a soft surface. Screw on the nuts, fit washers between the nut and the bush, then screw spikes into the bushes. Ensure each spike is screwed in approximately the same distance for easier levelling. Turn the loudspeaker over, place in position, and adjust spike height until stable and perfectly upright. Tighten locknuts without overtightening.

Use of Rubber Feet: For delicate flooring like parquet, rubber feet are supplied as an alternative to spikes.

Sandfilling the Base (Mission 733 only): The lower chamber of the Mission 733 speaker is an integral stand and can be filled with dense material like lead shot or dry sharp/silver sand (not builders' sand) for improved performance. Remove the plastic bung from the rear, push the supplied plastic bag through the hole, and tie a knot. Using a funnel, pour dry sand/shot into the bag, shaking the speaker slightly to settle the sand. Fill until just below the hole, tie a knot, push the end into the cavity, and replace the bung. Ensure sand is completely dry and never put sand directly into the cabinet.

Ancillary Equipment: The quality of your amplifier, compact disc player, turntable, arm, and cartridge significantly impacts performance. High-quality equipment, not necessarily expensive, is recommended. Mission recommends Cyrus amplifiers. Choose amplifiers with minimal gimmicks and controls.

General Precautions:

Always switch off your amplifier before changing any components or connections.
Do not use your amplifier at maximum power to avoid 'clipping' and damage.
Turn volume control down for a few seconds when switching on to prevent 'thump'.
Turn volume control to minimum when changing records, re-dialling tuners, or rewinding tapes.
Do not use filters, tone controls, or graphic equalizers; set them to '0'.
Do not expose loudspeakers to excessive cold, heat, humidity, or sunlight.
Do not connect loudspeakers to the mains electricity supply.
Ensure loudspeakers are correctly wired and in phase.
Do not use joined lengths of loudspeaker cable.
Do not mount loudspeakers by the rear panel; wall brackets must support the underside.
Retain packing materials for future transport.

Maintenance Features

Grilles:

To remove the grille on Mission loudspeakers (e.g., 760i, 761i & 780), grip the sides of the grille frame at the outer edges and gradually pull while holding the cabinet.
For 760i, 761i & 780 models, grilles are primarily removable for servicing. Locate the slot at the bottom of the grille and gently lever the frame off with a flat blade screwdriver, avoiding damage.

Cleaning: Mission loudspeakers are treated with a special sealant, making regular polishing unnecessary. Frequent wax polishing can darken and dull the finish. Use a lightly dampened soft cloth for cleaning. Occasionally, use a household spray polish applied first to a soft polishing cloth (away from the drive units) to restore sheen. If cleaning the grille, remove it first and brush gently with a soft, clean brush.

Drive Units: There are no user-serviceable parts inside the loudspeaker; the drive units are gasket sealed for life. Avoid dismantling the loudspeaker, as this will void the warranty. It is important for mid/bass drive units to be rigidly fixed. Occasionally tighten the fixings on the bass driver only. Do not touch high-frequency drive unit fixings.

Faults: If a fault occurs, return both loudspeakers as a pair, even if only one appears faulty. Use original packing materials for safe transit.

Guarantee Conditions: The guarantee is effective if completed by the Dealer and Purchaser and returned to Mission or their Distributor within 8 days of purchase. It excludes damage from accident, misuse, wear and tear, neglect, incorrect installation, adjustment, or repair, and liability for damage or loss during transit. Claims should be made through the Dealer. Mission is not liable for consequential damage. The Purchaser bears carriage costs. The guarantee is personal and non-transferable. Mission reserves the right to charge for examination and return carriage if equipment complies with specifications. Unauthorized servicing voids the guarantee. Retain a copy of your sales receipt for returns. These conditions do not affect statutory rights.

Mission 735 - Page 2

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