Mechanical/Practical Setup; Acoustical Setup Reference - ELAC Bass 130 Active Safety Instructions

Mechanical/Practical Setup

* 10 cm minimum free rear space is needed for proper cabling and heatsinking.
* Because of the numerous different placements possible, the cabinet of ELAC Bass 130 Active is supplied without
feet. Feet are not necessary on carpets. On solid ground a soft intermediate layer (rubber, felt, carpet surplus etc.)
should be used to protect surfaces and to avoid additional noises. On slippery grounds also Velcro with sticky tape
have been proven very effective.
Thick rubber dampers reduce the (small) vibration coupling into the floor construction, what sometimes has benefits
although the dominant noise transmission (into other rooms) is via sound pressure (acting on the room boundaries).
* If objects shall be placed onto ELAC Bass 130 Active, check them for freedom from rattle and safety against
slipping. The obligatory vase at least should be placed on a small lining. As a car accessory there are special mats
which prevent slipping.
With a rubber- or felt-mat it is possible and makes sense to put one of the main speakers onto the ELAC Bass 130
Active.
* Heavy bass amplitudes will stimulate all non-solid built parts of a living room and many furnishings to resonate. This
will increase the desired absorption, but also can lead to disturbing rattle noises, especially if metal and glass are
involved. Glass cases, cupboard doors, large lamps and flower vases and all items which stay upon or inside of
them are typical candidates. Source tracing can be difficult, because the noises are often hard to locate. Again, soft
materials as felt, fabric or foam will help as a support, lining and inset.

Acoustical Setup Reference

"Low frequencies need space" -- this common and for subwoofers vital statement is surprisingly ambiguous. But for
practical purposes the following facts should be more useful:
If a single ELAC Bass 130 Active is sufficient to produce substantial bass weight in a typical closed living room of, for
instance 25 qm or 70 cbm, then a free space (e.g. garden party) needs for similar weight ca. 4 units. Analogous two of
them will do the same in a large or very open room.
Sensitive ears with lesser sound pressure requests will go with the half, for techno/disco purposes you should double the
count respectively.
The low frequency limit of ELAC Bass 130 Active that is reproduced with nearly full level, is about 35 Hz. This corresponds
already to a sound wave with a length of about 10 m. Nevertheless it is possible to hear low bass even in small rooms
(extreme example: headphones). But there are peculiarities that have to be taken into account:
In a closed, box-shaped room with less than 7 - 8 m length the preferred listening location should not be located exactly
in the middle. Similar to the childrens fun in a bathing tub, the energy swings between both ends and builds up the
(alternating) pressure only there (till overflow), but exactly in the middle between is a pressure minimum, which means: no
(low) bass.
The following table shows the frequency where this effect appears most strong:
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