Set-Up Tips - ELAC SUB 2060 D Operating Instructions Manual

Set-up tips

General advice
• 10 cm minimum free space between the subwoofer and the wall is required for proper cabling and cooling.
• A few subwoofers are down-firing or provide a bass diaphragm on the bottom. Therefore, they are available
with mounted rubber feet/spikes. On shag carpets, the rubber feet should be replaced by spikes. The distance
between the subwoofer bottom and the floor should be at least 25 mm. If you want o place objects on the
ELAC subwoofer, make sure that they do not slip and that they are protected from vibrations. Shops for car
accessories may sell specific mats that avoid slipping. Mats of rubber or felt should be used in case a loud-
speaker shall be placed on the ELAC subwoofer.
Influences of the room acoustics
'Low frequencies need space' - this is a common and ambiguous important statement in regard of subwoofers. For
practical purposes the following facts may be more useful:
The low crossover frequency limit of the ELAC subwoofer at near-maximum levels is below 30Hz, depending on the
appliance. This corresponds to a sound wave with a length of approx. 10 metres. Nevertheless, low bass can also be
heard in small rooms (extreme example: headphones). However, but some peculiarities should be taken into account:
In a closed, box-shaped room with less than 7 – 8 m in length, the optimum listening position should not be located
exactly in the middle of the room. Like waves in a bathtub, the energy "rolls" back and forth between both ends and
the alternating pressure build-up is focused at these ends until overflows. The lowest pressure remains exactly in the
middle, i. e. no (low) bas. The following table shows the frequency at which this effect is strongest.
Distance between parallel walls
10 m
8 m
6 m
5 m
4 m
3 m
2.5 m (room height)
The effect appears exactly in the range where a Subwoofer should show its strength. It applies to all parallel boundary
surfaces, even to the floor and ceiling, if these are of solidly constructed. The solution is simple: slightly move the op-
timum listening position out of the centre - about 50 cm is sufficient to hear the low bass again. If the listener is sitting
directly in front of a wall, bass reproduction is often too strong. This can be balanced by reducing the levels at the
subwoofer. However, for all higher frequencies and a more natural space impression, it is better to move the listening
position to be located some distance from all of the walls. According to the acoustic theory of low frequencies in small,
closed rooms the location of the listener and subwoofer can be exchanged without affecting the acoustic results. Thus
the best position can be found easily by mounting the subwoofer at the potential listening position, walking around in
the room to locate the place where the bass is reproduced most evenly, and then placing the subwoofer there. Al-
though the theory never totally meets the practical demands to the full and the low bass should not be judged alone
(without the main speaker), the recommendation to never place the subwoofer/ listener exactly in the middle of the
room or centrally in front of long walls, still holds. Due to its flexibility, and clear-cut frequency range, the ELAC sub-
woofer can take full advantage of a location near a wall or in a corner. The minimum necessary free rear space for
cooling and cabling is 10 cm. More distance from the wall can be recommended only if the adjustment of "POLARITY"
does not provide a distinct advantage for either "+" or "- Shifting the subwoofer by 0.5 - 2 m (depending on the cross-
over frequency) may clarify conditions. Good bass sounds can be attained in open rooms and with slightly asymmetric
placements. All somewhat larger irregularities of the building, sometimes even an open door, may have a surprising
and usually positive effect. Under practical conditions the ELAC subwoofer will not be located by the ear and therefore
should not to be placed exactly between the main speakers. A position on a side wall, even behind the listener, is also
possible, especially with a low crossover frequency. Once the optimisation is completed, the subwoofer may even be
placed out of sight. There is only one serious restriction for the position of a subwoofer: it should not be placed much
closer to the listener than the main speakers (max 1 m).
Frequency of pressure minimum in the middle between the
walls
17 Hz
21 Hz
29 Hz
34 Hz
43 Hz
57 Hz
68 Hz
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