CD player output volume?

I just changed CD players in my system, and I originally was using a Rotel, and hooked up a Grant Fidelity(tube). I immediately noticed a huge change in volume. The Rotel is much louder. Why should there be so much of a difference is output from one CD player to another?
What Rotel model did you use?
You should check the spec on both player's output. Most are 2~2.5 V RMS through RCA and > 3.5 V RMS through XLR. Some do only 2~2.5 V RMS even through XLR.
Maybe the Rotel had significantly more VRMS than the Grant Fidelity? Were you using XLR or RCA through the Rotel? That also matters.
RCA. I checked specs on both, but neither show Output voltage.