Which processors to use ?

I would recommend a FIR processor because it is easier and more precise for correction EQ (and it can also correct phase). Here are some possiblities I have worked with (prices are approximate and indicated without VAT) :

  • QSC QSYS, max 16384 taps per channel (with max total about 4×8192 for model Core110F), completely configurable, multichannel ie 8in/16out , very very complete features but a bit costly (about 3600€ for the smaller Core110F)
  • Trinnov, max (about) 4096 taps per channel (with total depending on stereo or multichannel model), high end product but you can only use Trinnov’s own software to mesure and EQ, not cheap (starts at 3600€ for stereo models)
  • MiniDSP OpenDRC, max 6144 taps per channel (with total of 2×6144), cheap and stable, only available with digital I/O, cheap, less than 300€
  • MiniDSP 2x4HD, max 2048 taps per channel (with total of 4096 for all channels), very cheap, near 200€
  • Xilica Solaro QR1 or FR1, max 4096 taps per channel (with max total of 6×4096 but FIR cannot be loaded into presets so cannot be changed on the fly, contrary to QSys), completely configurable (not far from QSYS) with choice of different I/O boards and nice possibilities to remote with Ipad or Android tablets, competitive price starts at about 900€ for QR1 (8 slots for I/O boards) and 1600€ for FR1 (16 slots) without I/O boards (boards are quite cheap). Note that those processor can ran at 96kHz but the FIR length is still 4096 taps so less efficient in the lows…
  • softwares are cheap (or free ! ie BruteFIR) but need more configuration and sometimes not so easy for every user

All above processor also have IIR parametric filters so you can adjust the LF EQ if you have not enough taps for a precise correction in very low frequencies. In France, QSYS, Xilica and Trinnov can be bought at Company 44.1 (with optional configuration and on-site setup)