Channel frequency range not balanced


One channel coming from the turntable is `brighter` in sound than the other. The `highs` are clearer. I am using SME IV with standard phono cable, and vd Hul retipped Koetsu black. 
After many trials I have concluded that the problem lies somewhere between the RCA plugs and the stylus itself.
All sensible suggestions most appreciated!
lastperfectdaymusic
If you swap the channels at the cartridge, in the headshell, does the bright channel move to the other side? If so, it’s the cartridge. If not, it’s the cable or amps. Or your hearing. I assume it is not on other sources, so it would have to be the phono amp. Is it tube? If so swap tubes etc....
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If you swap the channels at the cartridge, in the headshell, does the bright channel move to the other side? If so, it’s the cartridge.

This.