Setup, Response Adjustment Switches - PSB VS300 Owner's Manual

VII. SETUP
Response Adjustment Switches
We at PSB have spent great effort to make the frequency response of your in-wall
system as flat and neutral as possible. This will yield accurate and pleasurable re-
creation of all manor of input materials: music, voice or movie soundtrack. Still,
variations in the listening position, room acoustics and listener preferences can be
accommodated using a few well chosen controls.
One of the most unique features of the VS300 is its correction for on-wall mounting.
The walls of your room and the proximity of the system to these walls will have an
effect on overall bass level as described above. With a bracket mounted on wall
VS300 there is also a very specific phenomenon stemming from wall mounting that
all on-wall speakers would share. Only the VS300 has a control to give a precise
correction of this effect.
An on-wall speaker radiates sound in all directions. The sound traveling forward is
the first to arrive at your ears. This "direct arrival" sound is similar to the anechoic
chamber response and getting it flat was one of the criteria of designing the VS300.
Sound travels backwards as well. That component of the sound will bounce off the
wall behind and then carry forward to arrive at your ears about 1 millisecond behind
the direct sound. The main impact of this delayed arrival is to put a significant
response "hole" in the sound of your system at 500Hz, or dead center in the human
voice range. This would disembody or thin out the sound of voices. A very
significant amount of extra crossover network is added to the VS300, along with a
switch, to compensate for this phenomenon. When the VS300 is wall mounted the
switch should be set to the "on wall" position per the graphic on the rear label. DO
NOT set the switch to "on wall" for any other mounting conditions such as stand
mounting or table top mounting with the optional bases. Even if such mounting puts
the system somewhat near to a wall it will degrade the response for any mounting
conditions other than the on-wall case.
The VS400 has its own unique response adjustment control. As it is a stand mounted
system and will never be mounted in contact with a wall like the VS300, there is no
need for on-wall compensation. But we feel that varying room acoustics and
personal preference, as well as other system factors, will give rise to a need for
subtle response adjustments that balance the bass end vs. the treble end of the
audible range.
To deal with this we have given the VS400 a control for "Spectral Tilt". This is a subtle
but effective 3 position control that gives the full audio spectrum a gradual uphill
slope toward the treble (Spectral Tilt +) or a gradual downhill slope (Spectral Tilt-) as
well as a flat or 0 position. Using the bass end as a hinge point the control tilts the
response about 2dB in total (+ or-) to give a subtle yet effective means of
"brightening" or "darkening" the overall balance. Although the anechoic chamber
response would be flat in the Spectral Tilt 0 position, don't be afraid to try the
alternate positions on a variety of program material and leave it on the setting that
sounds best to you.
Our goal is to provide listeners with completely convincing, "being there"
performance. Final judgments on the quality of the sound output are of course
personal. We encourage listening to the speakers with clear and familiar recordings
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