 |
stereo Imaging:
How well is a stereo image presented? Is it a
successful illusion transporting the listener into the acoustic space
used by the performers?
 |
Speakers: power response, matching of L&R
midrange and tweeter on-axis response, |
|
Cabinets: diffraction, resonances |
|
Crossover: phase continuity, group delay,
component tolerance |
|
Acoustics: symmetry in listening space, room
resonances, speaker placements |
|
|
timbre:
Are the instrumental voices in proportion and
harmony? Does one register complement another without conflict or
dominance?
|
Speakers: on-axis response, power response,
matching |
|
Cabinets: resonances |
|
Crossover: phase continuity, group delay |
|
Acoustics: room resonances, room modes |
|
|
transparency / detail:
Are the musical details audible through the
greater mass of instrumentation? Can the ambience of the recording
space be discerned?
|
Speakers: linear distortion, non-linear
distortion |
|
|
grain / hardness:
Is the music comfortable to listen to without
fatigue, particularly at high volume levels?
|
Amplifier: linear distortion, non-linear
distortion |
|
Speakers: linear distortion, non-linear
distortion |
|
|
dynamics / impact:
Does the performance have the ability to
startle and surprise the listener?
|
Amplifier: power output |
|
Speakers: power compression, linear distortion,
non-linear distortion |
|
|
fullness / body:
Is the presentation solid and firm? Is there a
foundation for the more lyrical elements?
|
Speakers: bass extension |
|
Acoustics: room modes |
|
|
presence:
Do the directional instruments like horns and
vocals project out towards the listener away from the rest of the
performance?
|
Speakers: on-axis response, power response |
|
Cabinets: resonances |
|
Crossover: phase continuity, group delay |
|
|
airiness / brightness:
Is the illusion of the space around the
original performers complete?
|
Speakers: treble extension, power response |
|
Acoustics: absorption |
The reason for fleshing out these attributes is
to illustrate the relative importance of the different elements in the
sound reproduction chain.
The loudspeakers affect every single parameter.
The room acoustics follow closely affecting 90% of the parameters.
Amplifiers have relatively little effect. This is not to undermine the importance
of quality amplification, but rather a comment on how good most
amplifiers are these days.
So in order to reproduce the original performance
or create a realistic illusion of a fictitious performance, requires an
understanding of the operation of speakers and their interaction with
the room in which they are deployed.
Interestingly, the attribute that demands the
most from the reproduction chain is stereo imaging. Stereo imaging is
a complex illusion that requires the coordinated contribution of all
of the elements in the chain of reproduction.
|
|
references
Before going on to look at speakers specifically,
let's have a look at room acoustics. It will be well worth the time
spent! Room Acoustics: a brief introduction
|
|
references
“Loudspeakers: What
Measurements Can Tell Us—And What They Can't Tell Us!"
AES Preprint 4608.
103rd Audio Engineering Society Convention, New York, September 1997. |
