Lyngdorf Audio Room Perfect TDAI 2200 - Manual (Page 10)

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system. On an ‘empty’ amplifier the menu system will guide you through the set-up sequence,
tell you when to move the microphone, oversee the quality of the measurements, and continue
the process until the necessary information is retrieved and the filters for ‘global’ and ‘focused’
correction can be calculated.
In normal rooms a listening position measurement and a minimum of 3-4 additional
measurements will be enough to get a RoomKnowledge of more than 90%, i.e. more than
90% of the information about the acoustic properties of the room. Of course you can continue,
or revert to the taken measurements and
add information at a later stage. When
setting up the system with the guided
process the measurements are analyzed in
real-time. The knowledge about the room
is calculated and if the measurement
positions have not gathered enough
information you are asked to continue to a
further measurement until there’s enough
information present for a proper analysis.
When sufficient RoomKnowledge has been obtained target curves and focus- and global filters
(listening position(s) filter(s) and the general room filter) are generated automatically. When
this is done the system will display a RoomCorrection index per filter, giving you an indication
of the level of correction carried out. A high number indicates big corrections and vice versa.
However, this number doesn’t necessarily indicate anything about the quality of your system!
For example a Lyngdorf 2+2 speaker configuration requires lots of correction – simply because
we created the system this way because we know that actually CAN make the necessary
corrections and that the final result will be even better!
Loudspeaker placement
When it comes to placement of traditional box loudspeakers it is actually possible to think
differently with RoomPerfect™, i.e. to break away from conventional ‘free space’ placement.
Normally, you need to choose a loudspeaker placement well away from rear and side walls to
secure the best possible frequency response. Due to the fact that a traditional box loudspeaker
has omnipolar dispersion in the bass region, this ‘free space’ placement has a big disadvantage
namely that you actually risk ‘destroying’ the impulse response. The reason for this is that you
hear both the direct sound from the speaker and later all the reflections from the walls. The
reflections are delayed as a consequence of the distance to the walls and will therefore arrive
later thus smearing the ‘attack’ of e.g. a drum beat. Typically back wall reflections are the
most annoying because they arrive from the same direction as the direct sound from the
loudspeaker. Side wall reflections are easier for the brain to cope with simply because they
arrive from another direction. Therefore they are often regarded as adding ambience and
localization clues.
If you place the loudspeaker close to the back wall the bass reflections from the wall and the
direct sound will arrive simultaneously at the listening position – i.e. the impulse response in
the bass region can be improved considerably and RoomPerfect™ can easily compensate for
the uneven frequency response as a consequence of the placement. So, with RoomPerfect™, it
can actually be an advantage to choose what’s normally regarded as a less ideal ‘close wall‘
loudspeaker placement as this will not only improve the impulse response. Also, when
compensating for the increased efficiency, the load on both amplifier and loudspeaker is
decreased whereby less distortion and better headroom is achieved. And taking energy out of
the system also has another advantage since pumping less energy into the room means that
room modes are less excited. Thus you achieve a much more even power response across the
room – i.e. the differences between peaks and dips in the response are reduced dramatically.