Digital room correction

Digital Room Correction is using a processor to correct the interaction between the speakers and the room.

Proper DRC requires measuring the response using a calibrated microphone at the listening position.
This measurement is used to generate a target curve, one that compensate for the amoralities caused by the interaction between room and speakers.

More about DRC


DRC can be implemented in dedicated hardware but it can be implemented in software as well.

Audiovero Abacus Preamp 14 CleanVolver 1345

  • stereo preamplifier with inbuilt convolver, AcourateCleaner and SqueezeLite streaming client
  • convolver fits to Acourate filters with standard length 65536 taps
  • automatic filter switch sync'ing to input samplerate
  • convolver hardware based on Raspberry Pi 2 and Cirrus Logic Audio Card
  • selectable Linux kernel 3.18.9 or 3.18.9-rt (realtime)
  • AcourateCleaner can be switched off individually for all channels
  • SqueezeLize: headless streaming client (Squeezebox emulator)
  • 7 inputs: 6 analog, 1 digital S/PDIF
  • channel 1 and 2 switchable between symmetric or asymmetric
  • channel 6 can be used as line-in or phono-MM (by jumper selection)
  • channel 7 samplerates 44.1, 48, 88.2, 96, 176.4 und 192 kHz
  • AD and DA conversion 24 bit
  • clipping indicator for input channels
  • variable symmetric and asymmetric stereo output + fixed gain asymmetric
  • outputs equipped by line driver modules of newest generation
  • high quality headphone output
  • home theatre bypass function for selectable all analog channels (1:1 volume gain)
  • microcontroller for channel selection, display and for memorizing of channel configurations
  • IR remote control in metal case
  • 3 linear power supplies for analog circuit, computer and microcontroller
  • switchable power plug
  • 110 VAC on request


Added 2016

DEQX HDP-3 Preamp proccesor AUD 6575

The HDP must be placed between the pre- and the power amp.

The signal from the pre-amp is converted to digital.

The DSP is applied and the result is converted by the DACs.


  • Provides DEQX Calibrated™ speaker correction for passive speakers
  • Provides DEQX-HD™ speaker correction for up to 3-way active speakers
  • DEQX-HD™ active crossovers; 48dB/octave to 300dB/octave linear-phase
  • Traditional active 3-way crossovers from 6dB/octave to 48dB/octave
  • Frequency-response of speakers typically corrected from 6dB range to 1dB
  • Automatically corrects phase and group- delay over typically 3ms window
  • 32-bit, floating-point, 240-MFLOPS processing with dual SHARC DSPs
  • Audiophile 24-bit 96kHz ADC-DSP-DAC processing and conversion
  • Provides anechoic measurement and detailed display for speaker correction
  • Provides room-measurement/display (non-anechoic) for room correction
  • Calibration Kit provides DEQX-calibrated measurement microphone
  • Two analog inputs: Unbalanced (2 x RCA) and Balanced (2 x XLR)
  • Two stereo digital inputs: S/PDIF (1 x RCA) and AES/EBU (1 x XLR)
  • Six analog outputs: unbalanced (6 x RCA)

DSPeaker Anti-Mode 2.0 Dual Core

Manufacturers description:

The new DSPeaker Anti-Mode 2.0 Dual Core room correction system can be used to correct any stereo audio system automatically. It utilizes a highly powerful DSP chipset for master grade room correction, the new dual-core VS8053 "IceDragon".

The new Anti-Mode Dual Core can be inserted between a pre-amp and a power amp (or active speakers). With automatic calibration and built-in TFT screen to display the room measurements, it offers the unmatched ease of use DSPeaker is famous for around the world.

In addition to the acclaimed Anti-Mode room correction, Dual Core also offers remote controlled USB-DAC /  S/PDIF-DAC, pre-amp, volume control and versatile EQ functions. All easily controlled with the featured remote control. Both balanced XLR/RCA connections are available, but also Pure-Digital mode where the corrected signal is passed through completely in the digital domain.


  • Automatically corrects any stereo system with userdefined frequency range
  • Remote controller
  • Can be used as a digital 1.1 crossover
  • Measures and displays the room response on a color TFT display
  • Supports multiple measurement points
  • Custom parametric EQs (notching, peaking, lowpass, highpass)
  • Easy to use House curve and Tiltcurve tools
  • Supports several independent "sweet spots", selectable with remote controller
  • Dual 6 MHz oversampling multibit DAC per output channel
  • Dual 192 kHz ADC per input channel
  • Pure Digital mode (Optical)
  • Digitally controlled analog volume control


Price: $1200 / €850

Ground Sound DCN28 € 4.217,00

DCN28 is a digital crossover, pre-amplifier and room correction in one unit.

DCN28 is supplied with the XOverWizard II advanced software which is a graphical tool to manipulate with inputs, outputs, gain, crossover frequencies, crossover slopes, equalization and delay. The software features measurement engine, post processing tools, optimizer engine with target option, output listing and direct transfer to the crossover setup environment.

  • 4 Digital Inputs (AES3-Coaxial-Optical)
  • 2 Balanced Stereo Analogue Input
  • 1 USB Audio Soundcard Input (galvanic isolated)
  • Digital controlled analogue attenuation on all outputs
  • 4-way stereo true balanced outputs
  • Digital PCM signal 32kHz-192kHz
  • Included XOverWizard II advanced software
  • Included Philips SRU6006 Remote
  • Optinal application code for Philips Pronto remote
  • Optinal code for Logitech Harmony Remote
  • Big Dimmerble Dot Matrix display
  • All in one Encoder Button controlling menu and values
  • 4 Power Amplifier remote trig outputs for 12V relays
  • Converter Resolution 24bit
  • Sample rate 96kHz
  • Total processing power: 180 biquads IIR
  • Frequency response: 5-48kHz (-3dB)
  • Latency input-output about 1ms
  • Low Standby Power
  • Dimensions: 430mm x 290mm x 100mm

Lyngdorf TDAI-3400 €5.799,00


Integrated amplifier with room correction.

Spotify Connect, AirPlay, internetradio (vTuner), DLNA (uPnP), USB


Measurements at Audio Science Review

Added 2019

MiniDSP DDRC-22D US$ 799


All digital Dirac Live® correction DSP with SPDIF/AES-EBU/Toslink interface.

  • Processor: 32-bit floating-point Analog Devices SHARC DSP
  • Input/ouput resolution: 24 bits
  • Maximum input sample rate: 216 kHz
  • Internal operating sample rate: 96 kHz
  • Output sample rate: 96 kHz
Added 2016
  1. Digital room equalisation - Michael Gerzon 1991
  2. DRC: Digital Room Correction - Denis Sbragion
  3. Acoustic and Psychoacoustic issues in Room Correction - James D. (jj) Johnston & Serge Smirnov