Mathaudio will not help. You have to make a REW measurments than you have to buy a Minidsp an upload the REW measurments into the Minidsp connect the analog recordplayer to the minidsp audio input which translatie an modify the analog input to a digital format which wil be translate back to An anolog signal to your amp. An possible other costly solution is looking for a pre or integrated amp with lyngdorf of dirac live incorporated which probably wil do the same with any analog input as Minidsp does. For instance NAD has such solution.
https://www.minidsp.com/products/minidsp-in-a-box/flex