effects loop question?

[DeadGoonz]

I have a tube power amp that I know very little about hooking up properly. So the question is should I run my preamp into the Line-in or should I use the effects loop? Or is the effects loop exactly what it says, a effects loop for effects only. Sorry if this is a dumb question but this is all new to me.

[bongomania]

Often the "return" jack on an fx loop is exactly the same as a "line in" jack. No difference in sound or function. However there are exceptions, so really you have to RTM to know in your specific case. As a side note for later, the fx loop is typically for line-level rackmount procesors, not pedals; so the important thing is the signal level, not whether it's "an effect".