Crest Audio VS900 - User manual

Vs900
POWER AMPLIFIER
Power Specifications 8ΩStereo 4ΩStereo 2ΩStereo 8ΩBridged 4ΩBridged
1kHz, 1% THD+N 250W 450W 550W 900W 1100W
Figures are Watts per channel, both channels driven.
Product Information
The Crest Vs900 integrates cost-effective design with exception-
al sonic accuracy, long-term reliability, and basic features
required for a variety of professional applications.
The Vs900’s remarkable price/performance ratio is the result of
innovative engineering and highly efficient manufacturing in
Crest’s modern USA facility–along with nearly two decades of
leadership in professional amplifier design. However, no com-
promises in component selection or quality control were permit-
ted as a shortcut to cost reductions. In every respect, the Vs900
embodies the Crest Audio tradition of roadworthy ruggedness
and reliability. For example, the Vs900 includes the same
TourClass®protection features as found in Crest’s CA, CKS,
CKV and CKX Series amplifiers. That means the Vs900 will
endure virtually any type of mishap or system stress–from uncon-
trolled ‘upstream’ oscillation to extreme ambient heat or acciden-
tal shorting–without damage to internal circuitry or connected
speakers.
Equally suited to permanent installation or mobile applications,
the Vs900 offers a welcome balance of exceptional audio perfor-
mance and overall value.
Vs900 Features
• Robust “Over-built” Power Supply - Massive filter capacitors
and a high output custom transformer provide ample current for
solid bass performance, even when driving low impedance loads.
• More Output Transistors - By using more output devices than
many comparable competitive models, the Vs900 puts less stress
on each device for a wider safe operating area (SOA) and long-
term reliability.
• Wide-Band Design - Frequency response extends from 10Hz
to 20kHz (-3dB at 165kHz), ensuring powerful sub-bass perfor-
mance as well as detailed, transparent high frequency response.
• Effective Cooling - Large, extruded aluminum heatsink and
front-mounted, two-speed 4-inch fan minimize internal tempera-
tures to prolong amplifier life.
• Rated for Sustained Operation into 2ΩLoads
• Front Panel Magnetic Circuit Breaker/Power Switch -
Eliminates need for AC line fuses.
• TourClass Protection Circuits
ACL (Active Clip Limiting) prevents speaker damage with
gentle gain reduction at clip threshold.
IGM (Instantaneous Gain Modulation) monitors connected
loads to detect conditions that may overstress output devices,
allowing safe operation into nominal 2Ωimpedances.
AutoRamp gradually increases gain to attenuator setting
level when the amplifier is turned on.
TourClass also includes protection from thermal runaway,
input overload, DC, short circuit, in-rush current, and turn-
on/turn-off transients.
• Rear Panel Detented Attenuators
• Differentially-balanced 1/4" TRS and Barrier Strip Input
Connectors
• Five-Way Binding Post or Speakon Output Connectors
(market dependent)
• LED Indicators for Signal Present and Clip (each channel),
Active, and Protect
• Stereo/Bridged Mono Mode Select Switch
• Five Year Warranty*

v. 2.3 5/20/97 B1000025
250 Watts
450 Watts
550 Watts
900 Watts
1100 Watts
52.3V
148V
10Hz-20kHz, -3dB @ 165kHz
20Hz-20kHz
ACL, IGM, AutoRamp, short circuit,
DC voltage, turn-on/off transient, current inrush,
sub/ultrasonic input.
<1.0%
<0.1%
>1000:1
> - 64dB
1.0 V
X40
>20kΩ/>10kΩ
-105 dB
> - 60 dB
AB
TRS (tip +) & Barrier Strip
5-way binding posts or Speakon
(market dependent)
38,000 µF
100V-240V, 50-60Hz
2.8A
7.2A
10.4A
15.0A
2000 BTU/hr
2900 BTU/hr
Front to Side via one 110 CFM, 2-Speed AC fan
Front panel: magnetic circuit breaker/power
switch. Rear Panel: 2 attenuators, mode select
switch.
1 Clip, 1 Signal per channel, Protect, Active
14 gauge steel
5.25" x 19" x 12" / 133 x 483 x 305mm
46 lbs. / 20.9 kg., 44 lbs. / 20.0 kg.
5 years*
8ΩStereo Power †
4ΩStereo Power †
2ΩStereo Power †
8ΩBridged Power †
4ΩBridged Power †
Max RMS Output Voltage (each channel)
Peak Output Voltage (each channel)
Frequency Response (+0/-0.3dB, 1W/8Ω)
Power Bandwidth (Rated power at 4Ω, 1% THD+N)
TourClass Protection
THD+N (rated power at 4Ω, 1kHz)
SMPTE IMD (rated power at 8Ω, 60Hz & 7kHz)
Damping Factor (10-400Hz at 8Ω)
Input CMRR (1 kHz)
Input Sensitivity (rated power at 8Ω)
Voltage Gain
Input Impedance (balanced/unbalanced)
Hum & Noise (“A” weighted, full power at 4Ω)
Crosstalk (“A” weighted, full power at 4Ω)
Class
Input Connectors (per channel)
Output Connectors (per channel)
Filter Storage
Power Supply (factory configured)
Idle Current Draw (120V)
1/8 Power Curr. Draw (typical music, 120V/4Ω)
1/3 Power Curr. Draw (continuous music, 120V/4Ω)
Max Curr. Draw (circuit breaker rating, 120V/4Ω)
Thermal Emissions (1/8 Power, 4Ω)
Thermal Emissions (1/3 Power, 4Ω)
Cooling
Controls
LED Indicators
Construction
Dimensions (Height x Width x Depth)
Gross Weight, Net Weight
Warranty
Architect’s & Engineer’s Specifications
The power amplifier shall have two channels. Each channel shall deliver a
minimum of 250 watts at 8 ohms, 450 watts at 4 ohms and 550 watts at 2
ohms, 1kHz, 1% THD+N. In bridged mono mode, it shall deliver 900 watts
at 8 ohms and 1100 watts into 4 ohms, 1kHz, 1% THD+N
The amplifier shall be front-to-side cooled, with a two-speed AC fan.
The amplifier shall have circuitry to protect itself and the speaker load
from output short circuits, DC voltage on outputs, and thermal overload.
The amplifier shall include circuitry to gradually increase gain to attenua-
tor setting levels when the amplifier is turned on, and circuitry for imped-
ance sensing and active clip limiting.
The amplifier shall have a voltage gain of X40 with an input sensitivity of
1.0V for rated power at 8 ohms. THD+N shall be less than 1.0% at 4Ω,
1kHz. The hum and noise level shall be 105 dB below rated output, “A”
weighted. SMPTE IMD shall be less than 0.1%, rated power at 8Ω, 60Hz
and 7kHz. The amplifier shall have a class AB output stage. The frequency
response shall be greater than 10Hz-20kHz +0/-0.3dB, 1W/8Ω.
The amplifier shall operate at 100V-240V, 50-60 Hz AC (configured at
factory). Maximum current draw shall not exceed 15 amperes at 120VAC,
(circuit breaker limited), with both channels driven continuously into a 4
ohm resistor.
A combination power switch/magnetic circuit breaker shall be mounted on
the front panel. Front panel indicators shall include an “Active” LED, a
“Protect” LED, “Signal” LED and a “Clip” LED (one per channel).
Gain attenuators shall be rear panel mounted. A rear panel Bridge/Stereo
mode select switch shall be provided. Rear panel input connectors shall be
an actively balanced TRS (tip +), and barrier strip for each channel.
Output connectors shall be Speakon or 5-way binding posts (market
dependent). Rear mounting ears shall be provided.
A rear-panel IEC AC mains socket or single AC mains cord having an
appropriate AC plug for the intended operating voltage shall be provided
(market dependent).
The packaging of the amplifier shall allow for standard rack mounting
without requiring space between similar units. Optional rack mount han-
dles shall be available. Dimensions shall be 5.25" (133mm) high x 19"
(483mm) wide x 12" (305mm) deep. The amplifier shall have a net weight
of 44 lbs. (20.0 kg). The amplifier shall be designated the Crest Audio
model Vs900.
Crest Audio Inc.
100 Eisenhower Dr., Paramus NJ 07652 USA
TEL: [phone] FAX: [phone]
http://www.crestaudio.com
Printed in USA
Vs900 POWER AMPLIFIER
SPECIFICATIONS
† Power figures are watts per channel, both channels driven, 1kHz, 1% THD+N. * 3-Year Warranty with 2 additional years is Registration Card is sent to Crest Audio. (USA, UK, Canada, and
many other countries). Crest Audio reserves the right to make improvements in manufacturing or design which may affect specification. Crest Audio specification literature is available in
downloadable PDF format; visit our website at: http://www.crestaudio.com. ©1997 Crest Audio Inc.
Serial Number
Designed & manufactured in the USA by:
Crest Audio Inc.
100 Eisenhower Dr.
Paramus New Jersey, 07652 USA
A+B
A B
++
BA
+
+
+
+
Ch.B Bridge Ch.A
Output Output
+
RISK OF ELECTRIC SHOCK
DO NOT OPEN
CAUTION
AVIS: RISQUE DE CHOC ÉLECTRIQUE—NE PAS OUVRIR
WARNINGTO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK DO NOT
EXPOSETHIS EQUIPMENT TO RAIN OR MOISTURE.
ATTENTION! POUR ÉVITER LE RISQUE D'INCENDIE OU DE CHOC
ÉLECTRIQUE, NE PLACEZ PASCET APPAREIL SOUS LAPLUIE OU Á
L'HUMIDITÉ
643-210
7
8
9
5
2
0
1
346
10
7
8
9
5
2
0
1
346
10
BA
CLASS 2 WIRING MAY BE USED
A+B
Serial Number
Designed & manufactured in the USA by:
Crest Audio Inc.
100 Eisenhower Dr.
Paramus New Jersey, 07652 USA
+
B+
A
A B
NL4FC
BA
A+B
643-016
+
+
7
8
9
5
2
0
1
346
10
7
8
9
5
2
0
1
346
10
BA
Rear View, Binding Post Version Rear View, Speakon Version (not available in North America)
B1000025