The standard output level of cd-players is often over 3V. My dac has exactly 3V. Cd-players used to be a lot louder than other components like tuners, cassette decks etc. which are usually at less than 2.5V. That’s the usual standard level, 2.5V.
On the input side there is supposed to be plenty of headroom. What happens when you feed to much amplitude is that the signal starts clipping, it starts distorting. And this is clearly audible. That is called overmodulation distortion. This can be accompanied by peaks in the signal, but those wil be filtered by the output- or power-stage. Highly unlikely that this will damage the speakers.
If you have an amplifier with a small power supply (ie a cheap amp) or a small amp and you try to drive low impedance dipping speakers at level 10, your output stage will start clipping and that can definitely distroy your tweeters. Even more so than lots of power can fry small woofers. But none of this will happen if you actually listen to the sound and turn the volume down when distortion gets bad.
Here is another thing that I learned when doing PA; every step of amplification has an optimal soundlevel to get the least amount of noise and distortion and the optimum dynamic range. If your microphones are to quiet on the mixing console you need to turn the power amps way up, causing a lot of noise (amplified from the consoles noise). If you drive the mixing console to hard, it starts overmodulating but you’ll have a lot less noise.
So, if your output of your Rose is low, into a normally rated 2.5V input amplifier you’ll lose dynamic range and get more noise. Not much, but noticable. Some preamps are more sensitive and like a bit lower input. I remember my Audio Note Oto had 2 tubes 12au7 and 12ax7 in series and was quite ‘hot’. I hardly ever went past 9 o’ clock on that 10W amp. I didn’t agree on that design. The person I sold it to removed the 12au7’s and he said it performed much better. But the Rose can cater to that by reducing the output.
So; 2500mV is standard. The rest is FYI
