mccormack micro phono drive

hello, i just bought this preamp without user manual, i 'd like to experiment with resistor/capacitor slot. I have searched high and low, but found nothing. Do you know how to do this or have manual? Thank you.

You need to open the case and look at the PCB. Each channel has a pair of sockets (marked "R/C1") next to the 47k5 input load resistors. The left channel load resistor is R12 and the right channel is R28 -or may be that is back to front!

So if you want to use different loading, then you get the desired resistor or capacitor, bend the leads carefully, and insert into the sockets. You wil need to calculate the correct resistor to place in parallel with the 47.5k input resistor to get want you want.