XiB4 Amplifiers


Linea’s XiB4 is a four channel amplifier suitable for use anywhere a powerful, clean sounding product with inbuilt DSP is required. Equally at home in portable PA, conferencing and contractor environments the XiB4 is the perfect choice in any application where being tamperproof is important.

XiB4 Features

  • 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

RMS per channel, all 4 channels driven
Model 2 Ohms 4 Ohms 8 Ohms
XiB4 1250W 800W 450W

Linea’s XiB4 is a four channel amplifier suitable for use anywhere a powerful, clean sounding product with inbuilt DSP is required. Equally at home in portable PA, conferencing and contractor environments the XiB4 is the perfect choice in any application where being tamperproof is important.

Remote operation is possible with Linea’s intuitive Podware PC application over BvNet, our installation friendly network. BvNet is an RS485 based system that allows many XiB4 amplifiers to be ‘daisy chained’ over hundreds of metres using low cost cables and without the need for network switches etc. Integration with other parts of a system is possible using dimple contact closure ports and Linea offer a range of interface units that allow seamless connection to Ethernet and Dante.

The XiB4 also provides extensive fault and status logging including driver integrity monitoring. These facilities are usually only associated with expensive specialised products and this is the first time that they have been made available as standard features for no additional cost.

The advanced 96kHz DSP is fully integrated into the product and provides an array of unique and genuinely useful features. Because all aspects of the DSP algorithms are designed and hand crafted in house by Linea, they are not available on products from any other manufacturer. For example, LIR linear phase crossover filters which are as easy to use as more conventional filter shapes, and have less latency than FIR filters.

Each of the XiB’s four channels can deliver 1,250 Watts RMS in to 2 Ohms continuously, or up to 2,500 Watts in to 4 Ohms for a bridged pair of channels. Unusually these are not, ‘transient’, ‘burst’ or ‘peak’ power figures, they are the power levels that are delivered by all channels simultaneously even when driven with the same dense program material.

With Linea amplifiers there is no need to ration power between channels, you can use all the power you have paid for all the time.

Linea can do this because state of the art components and a finely optimised design results in an amplifier that is more efficient than competitive products. This efficiency gain directly translates in to the generation of less wasted energy (heat). In addition to reducing energy costs high efficiency results in generous power reserves ensuring that pristine sound quality is maintained even under the most extreme conditions.

General Specifications­

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, 4 Ohm 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



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


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 link
LED 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).