where do I connect the earth in my pre to?

sorry, maybe I wasn't clear enough. Our local code also makes a ground mandatory, and my home has a pretty good ground (had a new one installed before moving in).

My comment about the ground pointed to why a ground and an earth connection? Lamm pres don't have built in phono stages, so why the earth?
I don't doubt the comment from Lamm is correct! Just wondering where I should connect the earth to. Water pipe? Anywhere? Ground in my power line?

Elizabeth is mostly correct, but not comopletely. It is common for preamps (and other components) to have this ground "lug", even in a unit without a phono preamp. The purpose is to ground various pieces of equipment to a common component to address ground loop issues.

However, that being said, my suggestion is similar to hers. If your system is hooked up/connected and you are not experiencing a ground loop, then ignore it/don't bother connecting your components via this ground lug. However, at some point if you do experience a GL, then you can use it to possibly address a GL problem.

Not connecting anything to this lug is not going to cause a problem in and of itself. It is a conveniece feature that can be used for the above referenced problems (in addition to other grounding schemes).

In some countries the term "earth" is used to mean the same thing that the term "ground" refers to in the USA, which in this case would mean chassis ground/circuit ground/ac safety ground (all of which are usually connected together in audio components that have three-prong power plugs).

So what is labelled "earth" on your preamp is just the ground thumbscrew the others have referred to, that is usually provided on preamps. It should not be connected to the physical Earth.

Some countries, including among others Russia and some parts of Argentina, according to this Worldwide Voltage Guide, appear to have only two-prong ac outlets. That would reduce or perhaps eliminate the potential for ground-loop problems, which is probably what was behind the comment that "the earth connection is for US electrical systems only."

Regards,
-- Al

OK, thanks for the feedback.

Al: that website is outdated. 3-prong installations are mandatory here. Also, it's not me using the term "earth"; it is printed on the back of the Lamm, which is a unit initially meant to be sold in the US.

I guess I'll forget about it: I don't experience any ground loops, no hum or hiss, except a little hiss I can hear with my ear to the tweeter and the volume wide open.
And I have no vinyl.

Thanks all for the input!