The MLEQ's are linear eq's they can be used on either the input or interstage depending on your response. The MEQ's can also be used on the interstage or input but these are your basic equalizer and the MCE are your cable equivalent's. You have the MREQ which is used for the return. As far as the MPEQ's I haven't heard of those unless they changed the labelling on them from the MEQ's. Antec used to provide those peakers (FSC-1 + FSC-2)for us but now I could only guess where to find them. You might try DB Tronics or Broadband International, they both specialize in after market plug-ins. Hope this helps.
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