Bien que ca me semble plus un sujet HC, je glisse ici l'avis de Hardesty, rédacteur du mag "Audio Perfectioniste" (
http://www.audioperfectionist.com ) sur les équalizers :
Equalization Can’t fix Your Room Acoustics
Introduction
Getting good sound from your home enter-tainment
system requires attention to set-up. You
can choose the best equipment in the world and
still be disappointed by the sonic results unless
you devote some time to adjusting the system and
the room that you put it in.
The contribution from the environment in
which it resides can make or break the sound of a
hi-fi system. Yes, your room is an important com-ponent
and, if it sounds bad, your potentially
great-sounding system may be overwhelmed.
Nothing I’m going to assert in this article is meant
to imply that the room is not an extremely impor-tant
aspect of the total sound. All I’m going to say
is that you can’t fix a poor-sounding room with
electronic equalization that alters the response of
the speakers. You must fix poor room acoustics
acoustically. Learning why you can’t fix room
acoustics by equalizing the speakers is important
in order to understand how to do it correctly.
Please don’t jump to any all-encompassing
conclusions. I don’t have a problem with equal-ization
per se. Recordings are equalized to com-pensate
for flaws in the equipment used to make
them and play them back. Speakers can be equal-ized
to correct response errors that should have
been fixed in the original design. In fact, that’s
what well-designed crossover networks are sup-posed
to do—equalize driver response errors.
Using an equalizer as a tone control to tune your
system to suit your specific tastes, or to make
poor recordings sound listenable, is a reasonable
concept, although I think that there are better
ways to do this. I don’t mean to condemn all
forms of equalization—just so-called “room EQ,”
also incorrectly referred to as “room tuning.”
I have a problem with the idea that you
can compensate for poor room acoustics by alter-ing
the response of the loudspeakers to make them
inaccurate in a complementary way. In a room
where the speakers and the listeners are properly
placed, well-away from the room boundaries,
“room EQ” simply does not work.
As powerful digital signal processors
become ever more economical, magic computer
boxes designed to fix all your acoustic problems
will be springing up like weeds. They work just
like traditional room EQ. They falsely assume that
the ear/brain mechanism can’t distinguish between
the sound from the source and the sound from the
room. When we start to actually tune the room
with acoustical treatment, you’ll see that the
sound from the speakers and the contributions
from the room are separate entities.
Caveat
This article is about the silly concept of
attempting to correct room acoustics by inversely
screwing-up the response of the loudspeakers. It
applies only to the important midrange frequen-cies
starting at about 130Hz and extending up to
perhaps 5 or 6kHz.
Below 130Hz or so, in a domestic living
room, room EQ is nothing but amplitude modifi-cation
with the equalizer acting as a multi-band
tone control. This may actually prove to be soni-cally
beneficial but there are better ways of
achieving smooth, detailed bass response and
that’s the subject of another article. At low fre-quencies
the ear can’t easily distinguish between
the sound from the speakers and the contributions
from the room, but I believe that you still need to
prepare the room for the best sounding results.
Above the lower-midrange even the most
lead-eared measurement freak has to recognize
that there are huge differences between the way in
which a single microphone captures sound and the
way in which two moving ears attached
)
