Crest audio VSL 460, VSL 900, VSL 1500 User Manual

SPECIFICATIONS

Clip

Protect

Signal

Active

Ch B

Ch A

CH B

0 dB

-1

-3

-6

-10

-15

-30

-80

CH A

0 dB

-1

-3

-6

-10

-15

-30

-80

Clip

Protect

Signal

Active

Ch B

Ch A

CH B

0 dB

-1

-3

-6

-10

-15

-30

-80

CH A

0 dB

-1

-3

-6

-10

-15

-30

-80

Clip

Protect

Signal

Active

Ch B

Ch A

CH B

0 dB

-1

-3

-6

-10

-15

-30

-80

CH A

0 dB

-1

-3

-6

-10

-15

-30

-80

Crest Audio Inc.

100 Eisenhower Dr., Paramus NJ 07652 USA

TEL: 201.909.8700 FAX: 201.909.8744

http://www.crestaudio.com

Printed in USA

VsL 460 VsL900 VsL1500

Output power into 8 ohm load 150W 250W 400W at 1kHz & 0.01% THD+N

Output power into 4 ohm load 240W 450W 750W at 1kHz & 0.01% THD+N

Output power into 2 ohm load 325W 550W 1000W at 1kHz & 0.01% THD+N

Bridged mono power in 8 ohm 450W 900W 1500W Bridged mono power in 4 ohm 650W 1100W 2000W Frequency response 10Hz–65kHz, +0/-0.3dB @ 1W into 8Ω Power bandwidth at 4 ohm 10Hz to 20kHz, @ 1% THD+N THD+N @ 1kHz <0.02% SMPTE IMD <0.1% Hum + N “A” @ rated 4 ohm power - 105dB Crosstalk “A” @ rated 4 ohm power > -60dB Slew rate 18V/microsecond Voltage gain standard Input CMRR @ 1kHz > -60dB Input impedance 20kΩ balanced, 10kΩ unbalanced Damping factor @ 100Hz >700:1 >1000:1 >1000:1 Input sensitivity 0.775V 1.0V 1.4V Output operating class Class AB Class AB Class H PSU reservoir capacitance 69 Joules 116 Joules 121 Joules Mains voltage 220V AC~50Hz AC power consumption @ idle 125W 150W 175W AC power consumption @ 1/8 700W 1250W 1850W AC power consumption @ max 1150W 1850W 2525W Dimensions H5.25" xW19" xD12" xD12" xD13.25" Net weight 33 lbs 36lbs 42lbs

PROFESSIONAL

POWER AMPLIFIERS

† 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.

v. 1.0 11/10/97

FEATURES

BENEFITS

SPECIFICATIONS

8Ω 250 watts

250 watts 8Ω

Competition

8Ω 250 watts

250 watts 8Ω

Clip

Protect

Signal

Active

Ch B

Ch A

CH B

0 dB

-1

-3

-6

-10

-15

-30

-80

CH A

0 dB

-1

-3

-6

-10

-15

-30

-80

VsL POWER AMPLIFIERS

Clip

Protect

Signal

Active

Ch B

Ch A

CH B

0 dB

-1

-3

-6

-10

-15

-30

-80

CH A

0 dB

-1

-3

-6

-10

-15

-30

-80

FEATURES AND BENEFITS

Crest VsL power ampliﬁers give you the same unchallenged excellence of sound quality and relia-

bility the world’s mega stars use. The VsL series of professional power ampliﬁers are speciﬁcally designed to achieve unsurpassed sonic performance and long term reliability - from sound installations operated with budgetary constraints.

Absolute sonic accuracy is the hallmark of these ampliﬁers with solid bass reproduction, deﬁned to the limits of audibility thanks to the “over-engineered power supply”, capable of delivering ample reserves of audio current. Wide-band output devices conﬁgured in the most advanced version of class AB and class H circuit design, assure detailed yet sparkling high frequency response. VsL series ampliﬁers also feature a comprehensive protection system, yet totally transparent to the audio path. Also Crest’s unique IGM circuit is included making it totally safe to use these ampliﬁers with load impedances as low as 2 ohm without any compromise in performance. For example it would be perfectly safe and professional practice to power four 8 ohm 250 watt speakers from each channel of a single VsL 1500 ampliﬁer.

Crest VsL ampliﬁers are built with high quality components, assuring long lasting operation.

VsL series ampliﬁers are built by the same factory that produces the audio industry’s leading quality ampliﬁers; Crest Pro series, used in touring sound systems all over the world all of the time. Any internal component is selected for premium quality and tested for durability.

VsL ampliﬁer printed circuit boards are machine assembled with the highest accuracy and passed through a rigid pre-testing procedure before being ﬁtted into the ﬁnished product and to assure sustained in-ﬁeld operation receive a rigorous “hot room” cycled burn-in, before going through a ﬁnal checkout test, performed by an automated state-of-the-art, precision audio measurement station, eliminating any possible human error in the interpretation of critical “product quality assurance” data.

Cool power and Hot music: The magic of Crest VsL ampliﬁers

Whilst for a single output device ampliﬁer, it would be true that the “thermal headroom” margin of a metal cased TO-3 style power transistor is larger than its plastic encapsulated equivalent, it is also true that modern power ampliﬁers use more than one pair, and Crest ampliﬁers uses plastic transistors in their output stages far in excess of competitive makers that use metal ones.

This means that every power transistor in a Crest VsL ampliﬁer works within a much larger “safe operating area” drastically increasing their long term reliability because of largely reduced waste heat generated by more traditional devices.

To off-set the thermal effects of increased ambient temperatures, the VsL design utilizes a specially designed extruded aluminum heat-sink with super efﬁcient dissipation characteristics, critically placed in the airﬂow path of an extra large fan assuring to keep internal temperatures of the output devices to a cool minimum, even under the most exhausting demands for power.

Vsl Cooling Scheme

Crest VsL ampliﬁers let you not only hear, but unmistakenly feel the difference in bass response from competing products.

VsL ampliﬁers, like all Crest amps, are constructed around an over-built power supply, with massive amounts of instantly available energy from a large capacitor storage reservoir and custom made high current power transformers. Mains voltage surges or spikes are electrical conditions that are largely outside your control and that’s why Crest gives you front panel mounted circuit breakers that function as a fuse as well as being the ampliﬁer’s power switch. If you encounter problems of this nature, simply ﬂip the switch and you’re back in business without suffering prolonged embarrassing silence.

The VsL 1500 can supply 1000 watts per channel into 2Ω; the competition can only supply 500 watts per channel into 4Ω.

ACL (automatic clip limiter) at the same time prevents severe distortion or feedback capable of destroying your loudspeakers because you accidentally pushed your mixer output level too high.

Active protection gives you Autoramp which guards your ampliﬁer and speaker cones against damaging spikes during power-up or down, apart from circuits that protect your ampliﬁer from becoming damaged because of thermal runaway, input overload, shorted outputs, dangerous transients or DC voltage appearing on the ampliﬁer’s output terminals.

Crest VsL ampliﬁers mean no further costly upgrades

With Crest VsL ampliﬁers running your sound you can be assured that upgrading has stopped because they are ampliﬁers with staying power.

Warranty

VsL Series ampliﬁers are covered by a unique warranty. All models are covered for three years as standard; Crest will extend this by two more years when the registration card is returned. This giv es ﬁv e years total coverage; conﬁrming our conﬁdence that these ampliﬁers will perform reliably for many years to come.

Product features

• High efﬁciency “toroidal” power transformer design.

• Utilizes the latest generation of “high speed” output devices.

• “Cool rack” front-to-side air ﬂow path driven by 2-speed DC fan unit.

• Electronically “balanced” TRS and cascade barrier input connectors.

• Universal 5-way “high current” binding post output connectors.

• “Multi mode” operation for stereo, parallel and bridged mono.

• Heavy gauge “ground lift” strap.

• Front panel mounted, “stepped-input” attenuators.

• Magnetic, “instant reset” mains circuit breaker/fuse.

• Front panel indicators for signal present, clip, active and protect.

• Three+two, parts and labor warranty scheme available.*

Built-in protection

• Active Clip Limiter, to prevent speaker damage.

• Instantaneous Gain Modulation, to prevent over-stress of the output devices.

• AutoRamp, to prevent damage from electrical spikes during switch on/off.

• Thermal, management to protect the ampliﬁer from conditions causing overheating.

• Protection of the ampliﬁer caused by adverse conditions in the output load.

• Protection of the speakers caused by adverse conditions in the ampliﬁer output section

Extra transistors and their effect upon thermal headroom

Choosing Crest VsL ampliﬁers is getting the best money can buy.

With built-in insurance through Crest’s exclusive world standard TourClass Protection and that includes protecting your loudspeakers as well. Crest’s comprehensive protection against abuse or failure is unmatched today with the following exclusive circuit designs featuring preventive as well as active protection.

Preventive protection includes IGM (instant gain modulation) allowing you to double-up on speakers without causing the ampliﬁer to prematurely suffer from overload.

The VsL series front panel indicators, attenuators and magnetic circuit breaker keep everything within sight and within reach.