following is based on a series of my postings
at DiyAudio.com from 25 March, 2008patchy amplitude response v. frequency
high non-linear distortion in a certain frequency range
built my first
speaker at the age of 16
and I was never
fully satisfied with my results since then; even when I became
more skilled, and learned more about acoustics, electronics,
mechanics, physiology of the hearing system, and human perception
in general ...
What is the search about ?
view has changed a lot in the
last few years. I always anticipated that minimizing 'errors' in a
technical way alone does not lead to good results. We have
to consider the qualities on which our perception system is based.
Today I think that trying to build good systems is to explore our
perception of things. It makes me wondering every time, when I
listen to a certain system, which gives rather good performance
subjectively while performing poorly from the 'measurement' point
of view. Some systems recognized as being 'good' by a wide
range of listeners suffer from obvious technical drawbacks like:
and so on.
imperfect examples are often
more instructional, than the exploration of a system which is 'known'
to be unobtrusive from the measurement point of view. This is because
it points me to what is important and what is not.
attempt here is to offer you my current, very
incomplete list of important and unimportant traits, maybe as fodder
for further discussion. I am sure that your 'lists' will differ, but
maybe there is some overlap:
frequency response at a fixed point in the listening room is NOT VERY
Smooth amplitude response outside the critical
bandwidth (say broadband telephony 0,2 … 7 Khz bandwidth)
at a fixed point in the listening room is EVEN LESS IMPORTANT
Large bandwidth is IMPORTANT
Balanced dispersion of energy over the entire
frequency range in the listening room as a whole
Controlled directivity which means
"no sharp discontinuities in horizontal and vertical
radiation angle v. frequency"
is VERY IMPORTANT
Spectral decay above the critical bandwidth is
NOT VERY IMPORTANT
Spectral decay at very low frequencies is
NOT VERY IMPORTANT
Spectral decay from mid-bass to the presence
range is VERY IMPORTANT
Invariance of all parameters considered important
against different power levels (especially against
very low power levels)
which are needed
for the perception of subtle
dynamic changes is VERY IMPORTANT
distinct pattern of "misbehaviour" of the reproduction chain like
a resonance pattern or
a pattern of sharp directivity changes vs. frequency or
a distortion pattern occuring at certain levels of power
makes the transducing device identifiable easily to
our hearing system and hampers it in its attempt to
compensate for 'minor flaws', which are allowed.