Keep in mind that we dont' know his preferred SPL and distance for listening. With that amp, running the 880s, i actually wouldn't expect alot of oomph at higher SPL.
Actually, I would expect that amp to get to “Rock Concert” levels. ( in a reasonably sized home listening space). It’s the dynamics which might be limited at extreme volume. I think the limiting factor probably has more to do with the audio chain. I.e. what’s the full output of each device v.s. Full expected input to the device after it.
