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ACS 4x2 | ACS 8x4


The KHE Amplifier-Cabinet-Selector is a switching system for guitar amplifiers and speaker cabinets.

Connect all your amps and cabs to the ACS and you’re ready to go.

Enjoy the fast access to your amplifier- and cabinet collection at your fingertip.

The KHE ACS-Series is the ultimate solution for any situation where more than one amp or cab is available:

  • recording studios

  • reampers & profilers

  • gear enthusiasts & collectors

  • music stores & showrooms

  • amp manufacturers

  • repair shops

  • gear reviews & comparisons

  • live musicians



working with multiple guitar amps and cabinets can be difficult:

re-patching different amp and cab combinations is time consuming and laborious.
it takes minutes to re-patch all cables and to power up the amplifiers.
it's a workflow killer and it draws on your creativity and inspiration.
great amps and cabs sit unused in the corner and don't get the attention they deserve.

imagine to have all your amplifiers and speaker cabinets available on your fingertips...


Connect all your amps and cabs to the ACS, power up the amps, and you’re ready to go.

Enjoy the fast access to your amplifier- and cabinet collection - right at your fingertip.


• ACS 8x4 : 8 amps + 4 cabs
• ACS 4x2 : 4 amps + 2 cabs

• no chance of activating an amp without load

• the presence of speaker cabinets is supervised

• amplifiers are safe & protected (int. dummy load)

• change amps and cabs by a push of a switch
• up to 2 cabinets at the same time

• compatible with tube- and solid state amps
• color coded jacks for easy wiring
• front & rear instrument input, tuner output

• midi controllable
• analog signal path
• digital control
• signal switching by
  high quality relays


switching tube amplifier is not that simple - bad and expensive things can happen if your amps sees no load.

it needs a well tought out concept to make the swichting process safe and reliable.

to make the KHE ACS as safe as possible, it features a number of safety features:

  • unused amplifiers are connected to a dummy load, simulating a speaker cabinet

  • unused amplifiers are muted, no signals can reach the poweramp

  • cabinet jacks are supervised for the presence of a cabinet

  • no cab can be enabled if no load is connected

  • no amp can be enabled if no cabinet is enabled 

  • i

    n case of power loss of the ACS, all amps are in a safe state

  • clever digital switching logic  to make sure no invalid combination is possible


a special mute circuit was developed to make the switching process as silent and as fast as possible.

the switching between amps and cabs is more silent than most amps channel switching.

the switching process is timed and supervised by a microcontroller for fast, percise and reliable switching.

the use of the user interface (switches and leds) is optimized for maximal user comfort and safety.

all jacks are color coded to simplify the wiring setup and to make sure not wiring errors happen.

the KHE ACS works with Tube- and Solid State Amplifiers.


the KHE ACS is built in Switzerland, using highest quality parts such as:

OMRON™ relays, NEUTRIK™ connectors, TI™ semiconductors, PANASONIC™ capacitors and AVR™ microcontrollers.

advanced shielding techniques are used inside the ACS to shield the sensitive input lines from the powerful output lines. 


  • ACS 8x4: 19", 1u

  • ACS 4x2: half 19" width, 1u

  • power handling: up to 150W

  • 2 year warranty

  • switching time: 3 - 12ms

  • contact resistance: < 0,1 Ohm

  • power consumtion: < 10W

  • crosstalk level : < 100dBu

  • input impedance: 2,2MOhm

  • ouput impedance: < 1kOhm

  • max. input-level: +15Vpp / +18dBu

  • frequency-range: 10-100kHz, +/-0.2dB

  • studio grade Hi-Z input,

        running at 30V for

        maximum headroom

  • noise floor: < 100dBu