DJames89 Posted July 5 Share Posted July 5 Hey there! I’ve got a bit of a humming issue with my turntable setup, which isn’t too uncommon. Here’s what I’m working with: Turntable - Audio-Technica LP3XBT (connected with Hosa/Amazon right-angle RCA and ground wire cable) Stylus - ATVMN95E Phono Preamp - NAD PP 2i (second-hand, near new condition) Speaker - Sonos Era 100 (connected via Belkin RCA to 3.5mm + Sonos adapter, usually grouped with other Sonos speakers) Power - All devices plugged into the same surge-protected power strip My setup is pretty new and entry level. Initially, I wasn’t planning on using an external phono preamp, but I found a good deal on a second-hand NAD and thought it might be better than the internal one. Everything is set up in a metal/glass cabinet (not ideal, but I’m short on space). The turntable and preamp are on different shelves, and I’ve kept the cables neat and connected properly. The Sonos speaker is about a meter away on a separate stand. Before adding the external preamp and using the internal one (directly into the Sonos speaker), there was no noise. But now, with the external preamp, there's a mild hum from the Sonos speaker. I’ve tried moving things around, which helped a bit. Unplugging the grounding wire made it worse! Lowering the Sonos line-in level from 10 to 8 reduced the hum to almost inaudible, but it also lowered the volume. Overall, it’s not too bad and the music sounds decent to me. I’m not expecting an audiophile experience haha. I can always return the NAD preamp and just stick with the internal one for now. Any tips or advice would be awesome! Link to comment Share on other sites More sharing options...
mbz Posted July 5 Share Posted July 5 What happens if you run a GND wire from the NAD phono to the amps GND connection. Keep the TT to phono GND wire in place. Hum increases? Most likely a 50Hz GND loop, sometimes worthwhile to check that it's not mains rectified 100Hz, more of a buzz. You can use mobile phone ap like spectroid or ... to check. Just to rule out a power supply issue in the NAD phono. Link to comment Share on other sites More sharing options...
DJames89 Posted July 8 Author Share Posted July 8 @mbz I think it's a ground loop issue! My turntable's ground is hooked up to the preamp, which then connects to my Sonos speaker through the line-in. There's no hum when it's just the preamp and the speaker, but it starts when I add the turntable. If I remove the ground, it gets even worse. It might have something to do with where the cables are placed, or maybe some WiFi interference from the nearby Sonos speakers. For now, I'm using the built-in preamp since it doesn't have any issues. I'll do some more troubleshooting later! Link to comment Share on other sites More sharing options...
mbz Posted July 8 Share Posted July 8 disregard... Link to comment Share on other sites More sharing options...
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