I'm about to embark on recording a box of LPs. Everything is set-up and my audio levels are good but I'm hearing a slight hum. It sounds like 60-cycle. My first suspect is that the record player is across the room from the receiver and is not grounded to the chassis. It's not grounded anywhere, come to that since it also has a two prong cord. So does the receiver so I don't think a three-prong plug gets me anywhere. Since this is a finite project, I could run some wire as discreetly as possible along the baseboards for the duration.
And I can't rule out that the technology itself is inherently noisy. I don't remember the noise before but it's been ten years since I actually listened to vinyl records. FWIW, the record player is going into the phono input of an Onkyo- TX-8160 and back out of the line-out into a Scarlett 2i2 interface. From there it goes USB to my computer. I'm using Audacity to record and the wave patterns look fine. I recorded the test song using FLAC and the playback sounds good too. It's not a wicked ground loop (got some experience there) and I haven't put a scope on the inputs looking for strays. My guess is that without the ground wire, it's picking up room hash on unshielded components.
Before I start peeling up carpet, does anyone have any ideas on getting the ground plane at the same level as the receiver?
As always, thanks for your experience and generosity. sh