Power Amp


CA 4D(1) 

 CA 4D front(1)

  Universal Controller Amplifier for all passive KS speakers



The CA4D is a 4 channel, 2,100 watt MOSFET amplifier driven into 4 ohms with control card system configuration technology using an analog controller card or the digital controller card exclusively supporting the KS Audio FIRTEC finite impulse response technology. The digital card is called FIRMOD 2. When changing controller cards or when downloading a new program / configuration from a chip card or a computer both the inputs and the outputs are appropriately configured to reflect the correct set up.


There are 5 basic program settings: - 4 single channels - 2 channel / 2 way - 2 channel with mono Sub woofer - 2 channel mono bridged high power sub woofer - 1 channel 3 way.

Whether or not the system is configured as a 2 in / 2 out or 2 way active or high-power bass bridge or additional activated cross over or bi-amping, etc... nearly every configuration is possible. This allows for a wide field of application from large concert-size sound reinforcement to speech producing the highest quality. The power supply is a PowerCon connector cable with a wide range switch mode power supply with power factor correction operating between 100 VAC and 250 VAC 50/60Hz.

On the rear panel of the amplifier there is an input socket for a remote stand-by that is switch-operated. It operates between 5 and 24 V. There are 4 mute switches corresponding to the 4 channels on the amplifier, each of these switches has 1 red LED below it to indicate the mute status and if the light is on the channel is muted. This feature is useful in many ways, such as when using this amplifier with monitors, you can mute individual mixes when they are not needed or, when you are tracking down problems.

The CA4D is equipped with 4 independent analog FET power amp modules. two modules supply a continuous 750 watts into 4 ohms each. And the other two modules supply a continuous 350 watts into 4 ohms each. The controller card and an applicable program determines the distribution of power to always deliver the maximum power available. The high performance of the CA4D amplifier is achieved by 3 independent balanced power voltage modules. The power losses are substantially less than with any other conventional power amplifier designs. A total of 72 quality selected power transistors, each featuring a P/V/max=250watts deliver a maximum headroom. Soft clipping circuits working in conjunction with the operating voltage, limit the NF signals before each power amp, which enables the power amp to always work with a high damping factor as well as remaining fully regulated.

The power supply is a state-of-the-art, heavy duty wide-range switch mode design, with Power-Factor- Correction (PFC) built in. The start-up voltage is limited to assure maximum protection. A second wide range heavy duty switch mode power supply including PFC is used to independently supply the controller card electronics along with the low voltage cooling fans and, to operate the stand-by operation via the remote standby switch. In the production of high output, high levels of heat are also generated as a by-product at the amplifier, which could damage the semi conductors. The reduction of these high temperatures is done with the installation of 2 independent cooling fans, thermostatically controlled. The air is taken in from the front panel inlet of the power amplifier thru an easy to clean filter and passed through to the back panel outlet while passing over the heat fins and the power transformer to actively cool these units down to nominal expected operating temperatures.

There are 4 Neutrik Speakon output connectors. These outputs are configured automatically by the controller card selected for the system. There are 8 balanced XLRs and are alternatively input or output, both for analog or digital AES/EBU signals.

The chassis is constructed of 1.5mm thick steel with rear mounting points available for extra security, and the face plate is constructed of 5mm thick aluminum and has 2 handles for ease of use.




Specifications CA 4D (without controller module)
number of channels four
frequency response + / -1dB 5 – 50,000Hz
output power per channel 2000W peak at 4 Ohms
output impedance min. 2 ohms per channel
power supply switchmode power supply with PFC
mains voltage powercon input (100/250VAC)
amplification mode Class H MOSFET, 3 rails supply
input connectors 4x XLR3 in, 4x XLR3 out
output connectors 4x speakon NL4
cooling 3 fans, speed controlled
case stainless steel
finish charcoal black
dimensions (height x width x depth) 3U / 19“ / 350mm(13.8“)
weight (without options) 14 kg / 31 lbs
features mounting slot for various KS Controller-Modules