Phono Cable Connection

phono in balanced

While Sy is watching, My turntable input of the RA88A mixer has the shields going to common RCA rings with the radio and CD player, and the minus of the all the 4558 op amps. (Now ST33078 op amps for less hiss). I have a little hum problem even with the turntable shell grounded to the mixer case. If I want to balance the phono inputs, do I put the RIAA caps and resistors that are on the plus op amp input, also on the minus op amp input? I've already bought a Stackpole RCA 4x2 array that does not have the rings common grounded across devices. (L & R ring same device are common). I have two phono op amps for two mag phono turntables, but I thought hooking the minus of one up to the black of the phono cartridge would help. It is a Shure V15 Era IV cartridge.The cables from TT mixer are now single wire in shield, but I bought some teflon twisted pair in shield cable for the upgrade. I'll have to cut some lands on the mixer PCB to isolate the op amp minus inputs, but this is DIY. There is plenty of room up in the air for a flying PCBlet.
 
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