Phono amplifier is designed for a phono signal amplification while using Turntables amplifier inside for special sound equalization circuit (RIAA) for restoring vinyl, it cannot be used for other purposes.
Method for checking noise sources
After phono player connected with the phono amplifier stage, if there is a significant low-frequency noise, you need to check in which part of the noise. First unplug the phono amplifier input signal cable to disconnect connection between them, if the low-frequency noise disappeared or significantly reduced, that may explain the noise from the phono player; obvious if the same or reduce low frequency noise , the noise it is very likely to put itself caused by phono amplifier.
It may cause a greater frequency noise that no specialized non-standard phono
Generally, non-standard phonograph is a turntable part of music center to cope with this set of sound designed, when external phono amplifier put to ground that could cause a large hum due to the different ground ways.