7
Adjusting the crossover frequency:
Apart from adjusting the phase, it is also very important to adjust the crossover frequency
of the subwoofer, to obtain perfect interaction between main speaker and subwoofer. This
is done by turning CROSSOVER FREQUENCY up and down until you sense that the
Adjusting the phase:
In order to obtain a perfect transition/blending between the subwoofer and the main
speakers, it is necessary to also adjust the phase control PHASE of the subwoofer. This
has to be done because the subwoofer and the main speakers have to co-operate in
producing sound in the frequency band around the crossover frequency. Therefore, it is
essential that the main speakers and the subwoofer are in phase. This means that the
speaker unit of the subwoofer and the woofer units of the main speakers work in step
with each other. Alternatively, the subwoofer and the main speakers might begin
counteracting each other around the crossover frequency, at worst resulting in almost no
sound being produced in this area at all (Fig. 6).
On the SWA 15, it is possible to adjust the phase continuously from 0° to -360°, corre-
sponding to precisely being able to match
any possible phase for a main speaker sy-
stem. Start with the phase control in the
minimum position and slowly turn it towards
the maximum position. The correct phase
is heard when the loudest output around the
crossover frequency is reached, while at the
same time the bass sounds as fast and
controlled as possible.
It may be a good idea to go back to fine-tuning the level as well as the crossover frequency
and phase, and possibly also the position of the subwoofer once or twice, as each individual
adjustment may influence the others.
Please note: It is not always the best solution to use identical adjustments for surround
and two-channel (stereo) hi-fi, so it may be a good idea to make a note of the adjustments
suitable in each case.
bass becomes perfectly even, with no dips.
(See Fig. 7). If the subwoofer has been
connected via the AUDIO IN - LFE socket,
the crossover network of the SWA 15 is not
active. This means that any adjusting of the
crossover frequency must be done
somewhere else in the system, and the
corresponding manual should be used for
reference.
Fig. 7
Fig. 6
All manuals and user guides at all-guides.com