I think they're kind of loud. I've heard people complaining about the 3ds volume in general, but I think it's fine. I never have mine set on max.
However, I have kind of sensitive hearing, so that may be why. General noises sometimes make me flinch in discomfort while everyone else goes on unscathed. And they set the tv to like 20, and it's a bit uncomfortable when I'm fine with it on 5. --- The following statement is false. The previous statement is true.