Bridge Mode - Peavey CS 8OOX Operating Manual

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BRIDGE MODE:

The bridge mode on stereo amplifiers is often misunderstood as to the actual operation and usage. In basic terms, when a two-
channel amplifier is operated in bridge mode, it is converted into a single channel unit with a power rating equal to the sum of both
channel's power ratings, at a load rating of twice that of the single channel rating. In this case the CS 800s is rated at 600 W RMS
per channel into 2 ohms. The bridge mode ratings are 1,200 W RMS into 4 Ohms (minimum load). The bridge mode operation is
accomplished by placing the mode switch into the bridge position, connecting the load between the red binding posts of each
channel, and then using channel A as the input channel. All channel B input functions are defeated.
Another application for bridge mode operation is to drive sound distribution systems in very large public address applications. In this
mode, the CS@ 800X power amplifier can actually drive 70-volt systems directly without using expensive matching transformers. The
real advantage of such an approach is primarily cost. 70-volt distribution systems are very common in domestic applications where
large numbers of relatively small loudspeakers are used for background music and paging. Such systems require the use of 70-volt
transformers at each loudspeaker. Another common use for the bridge mode is in subwoofer applications where very high output
power levels are required to reproduce extreme low frequencies. Such enclosures usually contain two or four loudspeakers to handle
the high power levels involved. For bridge mode usage, the enclosure impedance must be 4 or 8 ohms; never below 4 ohms! Also
make sure the enclosure can handle 1,200 watts reliably.
Peavey's patented DDT'" compression system enables the sound man to maximize the performance of the amplifier/speaker
combination by preventing the power amp from running out of headroom (clipping). This compression system is activated by a unique
circuit that senses signal conditions that might overload the amplifier and reduce the amplifier's gain when clipping is imminent. The
threshold of compression is clipping itself and no specific threshold control is used. This technique effectively utilizes every precious
watt available for the power amplifier to reproduce the signal while at the same time minimizes clipping and distortion, and thus
significantly reduces the potential of loudspeaker degradation and damage. The DDT system is automatic, hands-off approach to the
problem of power amplifier clipping.
Since the CS 800s power amplifier uses a circuit breaker for over-current protection, the DDT compression system plays even a
more important roll in the continuous performance by preventing each channel from clipping and overloading. Continuous operation at
clipping can cause the circuit breaker to trip, but with the DDT activated this problem is minimized. For this reason you should always
have the DDT compression system enabled.
OUTPUT POWER: (Typical value, 120 V AC, 60 Hz)
Stereo mode, both channels driven
2 ohms, 1 kHz, 1% THD, 600 W RMS per than
4 ohms, 1 kHz, 1% THD, 420 W RMS per than
8 ohms, 1 kHz, 1% THD, 260 W RMS per than
Bridge mode, mono
4 ohms, 1 kHz, 1% THD, 1,200 WRMS
8 ohms, 1 kHz, 1% THD, 840 WRMS
RATED OUTPUT POWER: (120 V AC, 60 Hz)
Stereo mode, both channels driven
4 ohms, 10 Hz to 20 kHz, 0.03% THD, 400 W RMS per than
8 ohms, 10 Hz to 20 kHz, 0.02% THD, 240 W RMS per than
POWER BANDWIDTH:
Stereo mode, both channels driven
TOTAL HARMONIC DISTORTION:
Stereo mode, both channels driven
10 Hz to 20 kHz, 4 ohm rated output, Less than 0.03%
HUM 81 NOISE:
Stereo mode, both channels driven
Below rated output power, 4 ohms, Greater than 100 dB
(30 kHz BW, unweighted)
DAMPING FACTOR:
Stereo mode, both channels driven
4 ohms, 100 Hz, Greater than 1,000
4 ohms, 10 kHz, Greater than 400
INPUT SENSITIVITY & IMPEDANCE:
Input attenuator set @ FCW
CHANNEL VOLTAGE GAIN:
Input attenuator set @ FCW
Stereo mode, 4 ohms, 1 kHz, 29 dB
Bridge mode, 8 ohms, 1 kHz, 35 dB
FREQUENCY RESPONSE:
Stereo mode, both channels driven
SLEW RATE:
Stereo mode, each channel - Greater than 40 V/US
Bridge mode, mono, Greater than 80 V/US
SQUARE WAVE RESPONSE:
Stereo mode, 4 ohms, 80 V P-P output
100 Hz waveform tilt, Less than 5 volts
10 KHz waveform rise-time, Less than 2 US (0% over-shoot)
PHASE DISTORTION:
Stereo mode, 4 ohms @ rated power
20 Hz leading waveform - Less than 6 degrees
20 KHz lagging waveform - Less than 15 degrees
POWER CONSUMPTION:
Stereo mode, both channels driven
COOLING SYSTEM:
Dual continuously variable speed DC fans
DIMENSIONS &WEIGHT:
Specifications sueect to change without notice.