K235 Stereo 3-Way Active Crossover

May-15-2024: Notice to our customers: We're currently running a short back-log of about 1-2 weeks. We will process orders in the order they come in. We apologize for the inconvenience. Thank you, SA

Transform Your Sound System with Professional Grade Active Bi-Amping or Tri-Amping.

The K235 Analog Stereo Active Crossover significantly improves the audio quality of your sound system by separating the high, mid and low frequencies using ultra-low noise, high precision active filter circuits. This allows the use of a separate power amplifier channel for each speaker driver to virtually eliminate the intermodulation distortion inherent with any passive crossover. The result is a massive improvement in the level of clarity, detail and warmth of the sound produced. This is called Active Bi-Amping or Tri-Amping.

Our primary goal with the K235 is to bring the benefits of high quality analog active bi-amping into the price range that is affordable to the average audio enthusiast. The K235 uses the highest quality audiophile grade components and has specs that match or exceed those of the higher priced analog electronic crossovers but without the huge price tag.

 K235 Features:

• Supports either 2-way or 3-way crossover operation
• Linkwitz-Riley filters, 4th order 24dB/Octave or optional 2nd order 12dB/Octave filter slope.
• Ultra-high precision 0.1% filter components give precise XO frequency selection.
• Allows you to Bi-amp or Tri-amp your sound system or add a sub-woofer to vintage audio equipment lacking LFE support.
• Supports 4-way or 5-way crossover operation by cascading two K235's.
• All analog design using only the highest quality audiophile grade components:
• Burr-Brown op-amps ~ Legendary audiophile grade op amps with .00005% Distortion
• Metalized Polypropylene Film capacitors with 2% precision
• Metal film resistors with 0.1% precision
• ALPS metal film potentiometers
• Neutrik XLR connectors
• Crossover frequency and slope is selected through pluggable 'XO Modules’.   
• Wide range of XO Modules are available to support any crossover frequency.
• Optional Sub channel L/R mixer to support a mono sub-woofer channel.
• Sub-sonic high-pass filter centered at 15Hz with 24dB/octave roll-off.
• Supports both Balanced and Unbalanced audio signaling on all inputs and outputs.
• True balanced signaling with fully differential and precisely impedance matched (+) and (-) signal legs.
• Sub, Mid and High output gain front panel adjustments.
• Baffle Step Compensation, with adjustable gain and 16x selectable baffle width ranges.
• Available with either 19” 1U rack mount or standard 17” faceplate.
• Made in USA
• 45 Day No-Hassle Return

 Specifications:

• THD Better than 0.00061%
• THD+N: Better than 0.0071%
• IMD : Better than 0.0085%
• SNR: 128dB
• Channel Crosstalk Less than -88dB
• Frequency Response: Linear from 20Hz - 250KHz
• CMRR (balanced input): Better than 70dB
• Input Impedance: 75K ohms unbalanced, 150K ohms balanced.
• Input Signal Max: 5.5V
• Insertion Gain: Adjustable -9dB to +8dB
• Filter Topology: Linkwitz-Riley, Constant Voltage, 4^th Order, 24dB/Octave.
• Enclosure: Aluminum Extruded Chassis
• Dimensions: 19”W x 8”D x 1.75”H (standard 1U dimensions)
• Shipping Weight: 7.5 lbs
• Power Supply: Internal Analog Bi-polar, 20,000uF total filter cap
• AC: 115/230 VAC, using standard C13 plug

 Audio Signal Inputs:

• Stereo Balanced: XLR-F Jacks
• Stereo Unbalanced: RCA Jacks

 Audio Signal Outputs:

• Stereo Balanced High, Mid, Low: XLR-M Jacks
• Stereo Unbalanced High, Mid, Low: RCA Jacks

Preview the K235 User Manual (.pdf)

We stock the following XO Module frequencies. When ordering, please specify your desired 'Sub' and 'Mid/High' crossover frequencies, as well as the slope (12dB or 24dB/octave) in the 'Special Instructions' box on the shopping cart page:

• Any multiple of 5Hz from 30Hz-100Hz (e.g. 30Hz, 35Hz, ... 100Hz)
• Any multiple of 10Hz from 110Hz-200Hz (e.g. 110Hz, 120Hz, ... 200Hz)
• 250Hz, 275H, 350Hz, 450Hz
• Any multiple of 100Hz from 300Hz-4000Hz
• Any multiple of 500Hz from 4500Hz-16KHz

You may want to experiment with various crossover frequencies and/or slopes. This can be easily done with the K235. Simply plug in a new XO Module to set a new crossover frequency.

The K235 comes with 2 XO modules. You can order additional XO Modules here

Questions? Please see our FAQ for many answers.

Trouble? Check out our Troubleshooting page.

To learn more about the advantages of active Bi-Amp'ing ~ 'Making the Case for Active Crossovers vs. Passive'