Question about FiiO X3 2nd gen

If I'm right, there is no 100db barrier, if that's what is meant. But what does it mean to operate it in large rooms? It is a player that has a lot of power (at gain=high or from the line-out/coax-out). Nevertheless, an amp should probably be connected in between for such use (as with high-quality headphones).

Meanwhile, I was able to test the FiiO. Yes, there is no volume lock. However, the operation is much less comfortable than with the iPod. When selecting songs, you only see text, no cover image.

Thank you for your answer.
Yes, I think that's what I mean by "100db lock". With the iPod Classic of the first generation, this lock could be bypassed (on the iPod and in iTunes) so I had enough output power to sound rooms up to 300m2 for disco. I tried "an amp" (Hama). But the battery is empty after 2 hours. That's not enough for me. I would have to have a headphone amplifier (amp) that runs for at least 8 - 10 hours. I am an adult educator and like to use the iPod in my seminars.