Hooking up vintage receiver and turntable?

It could be one of a few things.

The OHMs on older Marantz don’t match with some turntables. Also, some turntables are made specifically for the same model of receiver and will feed back on incompatible receivers. Or you could have a wire crossed. Or you could need to unplug a wire. It’s really hard to say without looking at your rig.

Answer by Seek’s Hubby

Turntables, compared to most other audio sources, are notorious for ground loop interference. Does the “feedback noise” you mention sound like 60 Hz hum? See if the turntable cable has a grounding wire (they generally did) that you can connect to a grounding post somewhere in back of the receiver. Also, route the cable so it’s not perfectly parallel to power cords—less likely to pick up hum.

Most turntables I own have a grounding wire that usually will be attached at the back of the amp. The problem may persist if your outlet is not properluy grounded. Usually florescent lights will exacerbate the problem. Do process of elimination and turn off any and unplug all devices plugged into anything close to where your amp is and light some candles and crank up the volume to see if anything has improved. Any turntable buzz I ever had was ground fault issues or having the turntable not on a solid surface and you then get harmonic feedback that increases as you crank the volume. Again process of elimination.

My best results are to have the turntable on an isolated surface, well grounded and behind the main forward facing speakers.

I like @Seek_Kolinahr s hubby. please join and post music/records related questions!!

@Seek_Kolinahr is probably right, but try removing the needle cartridge from the phonograph arm. Just a thought.

I remember the 70s.The ground thing is critical. The electrical fields in the rat’s nest of wiring behind a receiver can make that hum tough to crack. It’s a good idea to begin with the turntable as the first item you connect to the receiver. If the “hum” is there through your headphones when the turntable is the sole component, you can play with the cables to attempt to reduce the effect. With the addition of each component, don the headphones and check for the hum. Check with the new component switched “on”. Save the speakers for last. Sometimes the fault lies with the sensitivity of the pickup in the phono cartridge itself, and those things designed to track at a gram or less, well no 2 of them are the same. As stated above, you want to attempt to keep signal cables ( as much as feasible) away from power cables. In addition, you should make liberal use of contact cleaner on those connecting screws and RCA plugs and jacks on circa 70s equipment before installation. The other thing that’s critical about those low tracking turntables is that you MUST isolate them from vibration. Mounting your turntable on a rack or platform that in any way touches your speakers is just asking for “rumble”.