Run FM Tuner/Preamp to Pre-amp- Is this safe ?

Sounds OK to me since you're placing a line-level signal onto the next preamp input anyway. No doubdt it's amplified but wouldn't be to an overload level if you don't crank the volume controll all-the-way open on the tuner-pre.

It certainly won't interfear with any other components hooked-up to your current preamp safety-wise but whenever other components you're playing I'd suggest the tuner(or any other RF device) to be powered off(or at least you can switch to different mode your tuner-pre that basically powers tuner off).

You could always use the tape loop output of the adcom (I assume it has one) instead of the preamp outputs ... that way you would not have to use the adcom's volume control, which you could leave set to the minimum volume. I'm afraid I'm not familiar with the adcom pre, so please discount my post if it will not work in your particular case.

Thank you very much for your assistance. Assuming there is no inherent damage with this arrangement, it is cheaper to use the preamp tuner than spend the bucks for a new, separate tuner.

I agree you should use the tape-out connection on the Adcom, which removes the second volume control. It will be a much cleaner signal as well.