11
THEORY OF OPERATION
1. GENERAL
The Bose
®
Model 1800-V Professional Stereo Power Amplifier is an installed/portable amplifier made for
professional sound applications. It is a two-channel amplifier rated at 600 watts into 4 ohms and 450
watts into 8 ohms. In the bridged-mono setting it can deliver 1400 watts.
The protection circuits designed into the amplifier will protect the system from unexpected faults,
excessive temperature, continuous current limiting and shorted outputs.
The balanced inputs use high quality, high common-mode rejection differential amplifiers for exceptional
hum and noise rejection.
Through the use of equalization cards the amplifier can provide active equalization for Bose 402™,
502
®
A, 502B and 802
®
professional loudspeakers. These cards fit into the J6, Channel 1 and J7, Channel
2 connectors located on the Input Module motherboard.
Additional Features are as follows:
• Two input connectors per channel allow 1/4" TRS, XLR, or quick connect terminal block connection
• Two input connectors for each channel are wired in parallel
• Accepts balanced or unbalanced lines
• Independent CH 1 and CH 2 Level Controls with 11 detented positions
• Level Control Defeat Switch
• Dual Mono Mode for combining the power of both channels into a single higher powered channel
• Sequencer connection for sequentially powering-up multiple amplifiers to limit instantaneous in-rush
current
• Bi-Amp/Full Range configurable
• Internally configurable for Parallel Mono mode for single channel low impedance operation
• Internally configurable for 0.775V or 1.5V rms input sensitivity
• Internally configurable input polarity of XLR connectors
• Class H dual-rail power supply
• Additional protection circuitry includes Clipping Eliminator, AC Lines Fuse
• Power Connected/Standby Indicator
• 7 LED display per channel, including power ready and Clip/Protect indicators
• Two-speed fan cooled
Summary of Contents for 1800-V
Page 7: ...Figure 3 502A EQ Card HF Only Response Figure 4 502A EQ Card Full Frequency Response 7...
Page 8: ...Figure 6 802 EQ Card HF Only Response Figure 5 502B EQ Card Response 8...
Page 9: ...Figure 7 802 EQ Card Full Range Response 9...
Page 69: ...402 Equalizer Card Schematic 69...
Page 70: ...502A Equalizer Card Schematic 70...
Page 71: ...502B Equalizer Card Schematic 71...
