Well, yeah, you DID make the point that it's not grounding. I made the point that it IS grounding because grounding means more than your definition included. And in this post you call it grounding. Is it grounding? If it's not grounding, why aren't you calling in equipotentializing?

Make sure the tiny leads on the back of the cartridge are wired properly. Do you know the right config? Red/green right, white/black left. Be careful - fragile!

Make sure you bring a test receiver with you. You are in some trouble because you don't know if it is going thru a phono preamp or not, or so I read. If you get good sound through the phono input on the receiver, then there's no preamp. In that case, I wouldn't try to send a 5mv audio signal 70 feet. I would buy an outboard phono preamp to get it to line level. Note - if you plug into the phono input and it is terrifically loud or wildly distorted, then the signal has already passed through a phono preamp.

Your test receiver will reveal all you need to know.

If you've done all the things suggested here, or have chosen not to do some because you can see that what you've done covers the problems mentioned, it's time to call the manufacturer and tell them that you need a return authorization due to hum. Be sure to have a written list of how you've tested it with its normal cables (don't mention any experimenting you have done with added grounding wires) and tell them that it simply doesn't work and the client needs a good one.

This should shake things up a bit, either resulting in a replacement or resulting in them giving you some help that you wouldn't otherwise get.

Grounding is connectingbto earth and the other is called 'bonding'.

I walked by a Radio Shack a couple days ago. "Store closing, up to 90% off". Looking in the window, it seemed like there was more merchandise stuffed inside than usual. Probably they were attempting pump out as much dreck as possible. There was also a guy and a table out front trying to drive traffic.

In my opinion, even at 90% off, most of their stuff is not worth the bother.

Let me try again. From whatis.techtarget.com:

This definition includes exactly how you define ground, but makes it clear with the word "or" that there are more than only one definition of ground.

This is a second source where one definition of ground is that it's a reference point from which voltages are measured.

I don't know the uses of the term "bonding" outside of simple electrical wiring, but in many years of electronic work, I have NEVER heard "bonding" used when talking about chassis ground, signal ground, power supply ground, or any other common point used as the reference point from which voltages are measured in electronic equipment. I dare say it's not the proper term for what we call in audio connections to ground, to system ground, to chassis ground.

Everyone is sloppy about the use of "ground". Sometimes "ground" is literally a stake in the earth, other times a "ground" is only a reference point that implies "zero signal" -- for the device or stage being discussed. It is common to use multiple symbols on schematic diagrams to signify a "signal ground" (zero signal reference point) and a connection to the enclosure ("chassis ground"). In some high precision instruments, such as voltmeters that offer sub micro volt precision, there may be an ultra isolated section with its own "guard". This scheme is similar to our balanced system of protecting the signal with an overall shield that is not used as a zero reference. In some cases this guard is deliberately biased to some potential in an attempt to discourage leakage into the measurement.

Bonding is the word used for the metal strap, wire or clip with teeth that connects an engine to a firewall and/or hood on a car- these are often removed and left off when building custom cars because they don't look good, but they help to keep RF from exiting the engine compartment when the engine is running. If you have listened to AM radio and noticed a load of static when a classic car or truck pulled next to you at a stop sign or light, it's usually because they used solid plug wires or they left the wire/braided strap or clip off.

A bonding conductor is also required when the electric service has a main breaker panel and at least one sub panel.

[Link: ecmweb.com]