Rel sub question?

Should be.

Connecting yellow and red together to the positive speaker terminal and black to the negative terminal.

thanks for response....just wasn't sure if there would be any ill effects on amp or not...?

What is the rest of your system?

I have 2 Stadiums connected and have done it the way Lapierre suggests but when I talked to Sumiko this fall they told me to connect the black wire to the amp ground terminal rather than the ground speaker terminal. I am doing this and it works, the other worked fine also. I am not sure what the difference is. I would check with them, they are very helpful and have a very good set up manual for REL on their web site.

You are less likely to get any grounding hum when you ground to the amp. There is no sound difference between the two grounding connections.