Linea Research XiB4 Power Amplifier

• Four channels of sonically pure Class D amplification
• Unique, precise, 96kHz digital signal processing
• Over‐designed switch mode power supply
• 85V to 240V Auto-sensing PSU
• 5,000 watts RMS total output
• Tamper proof front panel
• USB and BvNet network operation
• Powerful grouping & multi‐layer EQ
• Fully designed and engineered in house by Linea Research
• Manufactured in the UK

General

• Number of output channels:  Four
• Total power output, all channels driven:  5,000 Watts RMS
• Audio inputs:  4x Balanced Analogue
• Digital Signal Processing:  High performance 96kHz DSP on all inputs and outputs
• Control, monitoring and system status:  USB and BvNet (optimised RS485)
• Contact closure ports for voice recall and system shutdown
• Power-save modes:  Standby after user defined time with fast wake up on audio detection or from a network command

Power Output

• Power specification:  RMS output all channels driven with continuous program material and a nominal ambient temperature of 40ºC / 105ºF
• Crest Factor of 4 (12dB), 2-Ohm nominal load:  1,250W per channel:  
• Crest Factor of 2.8 (9dB), 4-Ohm nominal load:  800W per channel:  2,500W per bridged pair
• Crest Factor of 2 (6dB), 8-Ohm nominal load:  450W per channel:  1,600W per bridged pair
• 25V line (CV) operation, Crest Factor 4 (12dB):  625W per channel:  
• 70V line* (CV) operation, Crest Factor 4 (12dB):  1,250W per channel  *can drive 70V line to -2dB max.:  2,500W per bridged pair
• 100V line* (CV) operation, Crest Factor 4 (12dB):  1,250W per channel  *can drive 100V line to -5dB max.:  2,500W per bridged pair

Audio Performance

• Amplifier topology:  Linea Research high performance Class D
• Amplifier modulation scheme:  Low feedback, multiple loop, with feed-forward error correction
• Output noise, ref. maximum amplifier output:  Better than 106dBA typical, unmuted
• Gain (with all the DSP level controls set to 0dB):  27dB
• Frequency response, 4 Ohm load:  20Hz to 20kHz, +/-0.5dB
• Total harmonic distortion, THD:  <0.05% typical, 1kHz signal, AES17 filter, 4Ohm load
• Inter-channel crosstalk, worst case combination:  better than -80dBr at 1kHz
• Slew rate:  >25V per microsecond typical
• Damping factor (Ref 8 Ohms):  >100 at amplifier output (see Linea’s “Damping factor debunked” white paper)
• Maximum analogue input level:  +20dBu
• Analogue input sensitivity range for full output:  0dBu to +20dBu, continuously adjustable
• Analogue input (four channels):  Input 10k Ohm, electronically balanced, link directly connected to input
• Analogue ground scheme:  AES48 standard compliant

Digital Signal Processing

• Resolution:  40 bit, using Linea Research proprietary algorithms
• Sample rate:  96kHz throughout
• Input processing, per channel:
  • Input signal routing, Delay, Gain, Phase, Mute
  • EQ: 4th order HPF, 4th order LPF, 8x Parametric, Low and High shelving filters
• Output processing, per channel:
  • Source, Delay, Gain, Phase, Mute, up to 8th order crossover filters, intelligent limiter
  • EQ: 6x Parametric , Low and High shelving filters
• Crossover filter types:  Bessel, Butterworth, Linkwitz-Riley, Hardman (Like Linkwitz-Riley but with better out of band rejection)
• Pre-set management:  4 voice pre-sets per channel pair, selected by contact closure

Power Supply

• Topology (main power supply):  Linea Research high efficiency Series Resonant
• Nominal mains input voltage range:  85V to 240V, Power supply automatically detects voltage and configures accordingly
• Mains input frequency range:  47Hz to 63Hz
• Mains inrush current (max for <10ms):  23A at 115V, 46A at 230V

Protections Systems

Under all circumstances the control and protection systems will endeavour to deliver the maximum power possible for a given set of conditions, applying limiters only in extreme circumstances. Muting will only occur when a dangerous situation is detected, normal operation automatically resuming when the condition clears.

• System protection:  Speaker protection
• Excessive power supply current (per channel pair):  Sonically clean audio limiter
• Excessive internal temperature (per channel pair):  DC offset protection
• Mains voltage within acceptable limits:  Internally stored information
• Output current within limits (each channel):  Log of temperature over time
• Driver impedance within limits (each chanel):  Log of protection gain reduction over time
• Power throughput within limits (each channel):  Log of output current over time (each channel)
• Switch on mains surge:  Power cycle count

An inbuilt notification system is provided to indicate problems to remote devices via the network

Physical

• Cooling:  Vari-speed fans, back to front airflow
• Analogue IN and LINK:  4x female and 4x male Neutrik™ XLR
• Amplifiers output:  4x Neutrik Speakon™ NL4 connectors
• Mains input:  Neutrik 20A Powercon™
• USB:  Standard USB ‘B’
• Network (BvNet):  RJ45 in with RJ45 daisy chain link
• Contact closure and shutdown inputs:  RJ45 in with RJ45 daisy chain linkLED indicators:  Bright, easily differentiated
• Operating temperature range and humidity:  0 to +40ºC, (+32 to +105ºF)          0 to 80% RH (non-condensing)
• Enclosure:  Standard 19” 2U (88mm), 360mm (14”) deep (from rear panel to front rack support)
• Optional accessories:  Rear rack support kit
• Net Weight:  9.5kg (20 pounds).