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I found the discussions on the recent thread started by Hifiwolf quite interesting, but think that DSP deserves more attention. As Serge and others point out in the other thread, DSP is not a panacea that will overcome truly awful room acoustics or poor placement, nor will it replace proper acoustic treatment. But if – like most of us on this forum – you don’t have a dedicated listening room, which limits options for speaker placement or room treatment, then DSP is well worth a try IMO. I’m posting to share my experience in case anyone else wants to have a go. My ~6m x 3.5m listening room doubles as a living room, so I have no option but to place my speakers (Audio Physic Avanti IIIs) roughly 2m apart along the longer dimension, about ~0.5m from the back wall, with each speaker ~2m from the nearest side wall. My listening position is almost nearfield – about 2m from the speakers, near the opposite wall. Room EQ using the recently released miniDSP 2x4HD unit (which I got from Keith at Purite Audio) has made a major difference at relatively low cost (~£200). The 2x4HD has analogue and toslink digital in, can work as a USB DAC, and has analogue outputs for up to 2 subs besides the main speakers. Any standard TV remote can be programmed to select inputs, digitally control volume, mute etc. Measurements with REW freeware (which can be downloaded with a complete set of instructions from http://www.roomeqwizard.com/ ) and a calibrated microphone (UMIK-1, also from Keith at Purite Audio) at the listening position showed this frequency response (1/6 octave smoothed) (image below= before correction, the 3 curves show the responses from both channels + sub below 600Hz and the L or R channels separately from 450-20kHz): It is quite clear that the frequency response is not optimal, particularly between 30-500Hz – probably a combination of room acoustics, speaker placement and the effects of the passive crossovers within the speakers themselves (the drive units in the Avanti IIIs cross over at 200Hz (6dB/octave), 500Hz (6dB/octave), and 2.2kHz (18dB/octave)) EQ using REW (which automatically generates filters that can be directly uploaded into the miniDSP 2x4HD unit) allowed this equalized response with L+R channels and sub across the 10Hz-20KHz range (also 1/6 octave smoothed) (image below= after correction): I can clearly hear the improvements after EQ - it really is night and day. I’ve tried out a few other pairs of speakers before and after DSP done in a similar way, and in all cases, there has been a marked and easily audible improvement. I haven’t used many of the very flexible capabilities of the MiniDSP 2x4HD unit - for example, it could be used as an active crossover for active bi-amping, and even allows FIR filters for phase correction. Also, miniDSP has recently released a firmware upgrade for ~£200 that gives the 2x4 HD unit Dirac live capabilities – so the unit will automatically scan the room response, and calculate the right FIR filters including phase correction and sub integration, provided you plug in a calibrated microphone like the UMIK-1. This will be useful for those who don’t want to mess around with REW themselves. All in all, a big improvement in sound for an ~£200 outlay.