Genelec 7070A, 7071A Minimum clearances to walls Or other objects, Setting the input sensitivity

Phase Difference: 0°	Phase Difference: 90°
85 Hz	85 Hz
Phase Difference: 180°	Phase Difference: 270°
85 Hz	85 Hz
Figure 4. The effect of phase difference between the subwoofer and the main monitors

Table 1. Suggested Bass Roll-Off settings

Figure 5. Flush mounting the subwoofer. Note the clearance needed on the reflex port side.

Although the 7060A, 7070A and 7071A subwoofers are magnetically shielded, they may cause some picture distortion if placed near very sensitive video monitors or com- puter displays. Move the subwoofer further away or try turning the driver side of the subwoofer away from the screen.

Minimum clearances to walls

or other objects

The power amplifiers are attached to the lower part of the aluminium grille, which func- tions as a heatsink. Do not cover the grille or place the subwoofer so that there is less than 10 centimeters (4") of free space in front of the grille.

Make sure that the space underneath the subwoofer is clear from obstructions. Thick carpets may block the ventilation clearance needed for cooling the electronics' box.

The reflex port side (opposite of the ampli- fier panel side) should always have a clear-

fier cooling. This can be done by making the recess 7,5 centimeters (3") wider than the subwoofer. Place the subwoofer into the right end of the recess with the driver side facing the room. This leaves sufficient 7,5 centime- ters (3") of free space on the reflex port side. The height and depth of the recess should not be any bigger than those needed to fit the subwoofer flush with the wall surface.

Setting the input sensitivity

The subwoofer requires input sensitivity alignment to the source to obtain a correctly balanced system. The input sensitivity con- trol is located on the amplifier panel of the subwoofer. An input voltage of -6 dBu with a -6 dBu input sensitivity setting will produce 100 dB SPL @ 1m in free field. To obtain a 110 dB SPL output an input voltage of +10 dBu is required when the input sensitivity is set to 0 dBu.

panel. Table 1 provides some suggestions for the "Bass Roll-Off" switch settings. When both roll-off switches are set to "OFF", a flat anechoic response is obtained.

Setting the phase control

Incorrect phase alignment between main monitors and subwoofer causes a drop in the frequency response of the whole system at the crossover frequency. The graphs above (Fig. 4) show the effect of phase difference to the frequency response.

The phase difference between the main monitors and subwoofer at the listening posi- tion is dependent upon the position of the subwoofer, so the phase adjustment should be done only after the preferred position is found. Acoustic measuring equipment is required for accurate system alignment. If this equipment is not available, the following coarse phase matching can be applied.

ance of at least 7,5 centimeters (3") to any objects to ensure proper functioning of the

Setting the Bass Roll-Off	Coarse phase adjustment
switches	method

reflex port.

Flush mounting the subwoofer

If the subwoofer is flush mounted into a wall or a cabinet, it is important to ensure unre- stricted airflow from the reflex port and ampli-

The acoustic response of the subwoofer may have to be matched to the characteristics of the room and the positioning in which it will be used. To adjust the subwoofer to match these characteristics use the ''Bass Roll-Off' control switches located on the amplifier

Genelec 7060A, 7070A and 7071A subwoof- ers are equipped with a built-in 85 Hz fre- quency test tone generator for easy phase alignment. The test tone generator is con- nected to the subwoofer's "FRONT CENTER OUT" channel only. In a stereo system it is