Toe-In And Distance Between Speakers; Additional Information; Specifications - Acoustat SPECTRA 1100 Owner's Manual

Wall: Since the Spectra is a
Distance From The Rear
dipole loudspeaker (producing soundfrom bothsides)
placing the speaker too cbse to the rear wall will yield
reduced bass output, due to rear-wave cancelations.
A minimum speaker-to-rear wall distance of 3 feet (1
meter) is recommended, as measured from the rear
center of the array perpendiilartothewall. Note also
that the distance to the rear wall can be used in some
situations to adjust the low frequency balance in the
room.
W a l l s : Some space is desir-
Distance From The Side
able from the side walls, but the asymmetric nature of
Spectra's horizontal high frequency radiation makes
side wall reflection less of a problem than with most
otherspeakers. Aspacingof foot (30 cm) is the mini-
1
mum recommended distance from the side wall to the
array's outer edge. In wide rooms, of course, this
distance may be much greater.
And Distance Between Speakers: There are
Toe-In
numerous combinations of toe-in angle and distance
between speakers that will yield excellent sonic per-
formance. In most situations, the distance between
speakersshouldberwghlyequaltothedistancefrom
each speaker to the listening position. The speakers
should also be toed-in at an angle so that they more-
or-less face the listening position.
Between The Speakers: This area
The Area
kept clear of major obstructions to airflow
imaging is to be achieved. The size, shape, and
material of any objects placed between the speakers
will determnie theextentof any negative effects on im-
aging.
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ADDITIONAL INFORMATION

should
be
if optimum

Specifications

PHYSICAL DIMENSIONS:
........................................
Height
.........................................
Width
...............................
Array Depth
............................
Woofer Depth
RECOMMENDED AMPLIFIER POWER:
-
75 100 watts perchannel or greater (based on 8 ohm
amplifier rating). See further discussion under
"Amplifier Recommendations".
BIAS POWER SUPPLY CONSUMPTION:
Less than watts.
10
EFFICIENCY 88 dB SPL'
(400 Hz, 1 watt into 8 ohms equivalent at one meter,
extrapolated from measurements taken at 10 watts
into 8 ohms equivalent, measured at a distance of
3.16 meters.)
IMPEDANCE: Typically greater than 6 ohms, mini-
mum of ohms at high frequencies (see graph).
2
FREQUENCY RESPONSE: -3 dB at 30 Hz, -3 dB at
kHz ("High" setting)
19
CROSSOVERS:
250 Hz. -6 dB per Octave electrical,
Electrostat:
dB effective acoustic rolloff.
-12
250 Hz. modified
Woofer:
internal phase reversal.
14
67.5" (171.5 cn)
cm)
16' (40.6
3" (7.6 cn)
16.75" (42.5 cn)
2 dB per octave,
-1