I have a cheap Scott turntable equipped with a low priced Audio-Technica mm cartridge through a cheap Berhringer pre-amp into a Logitech Z-680 speaker system. I also have a CD player separately into the system.If the Berhringer is a phonostage, then I assume all sources are plugged into the Logitech. There are no specs listed, but it accepts line level inputs.
The budget AT carts I looked up are rated at 3.5, 4.2, and 5.0mV at 1 kHz. So it seems that a MM cart into a phonostage with 35dB gain is too low.
https://www.amazon.com/Logitech-Computer-Speakers-5-Speaker-Silver/dp/B00007AKDP