Hi,
Are you sure you actually mean level limited? 88dBa seems very low for max SPL. And I don’t know many headphones where there is level limiting in the headphones. Usually limiting is done at the output stage of whatever it is you hook them up to (like the iDevices have built-in limiting). It does make sense if 88dBa is the efficiency of the headphone though. In which case there is two options, running your headphone level on the controller higher and/or getting an in-line (battery-powered) signal booster. Someone else on the forum bought one recently (because his controller had a very low output level, so the other side wasn’t capable of enough power) and I think it worked fine.
If I am not mistaken, the 480s stem from the 90s, making them not the most recent of models. Also I seem to remember they were somewhat of an audiophile choice. And somehow that doesn’t always translate well to DJ-ing environment (which is different yet again from production/studio work). I don’t know what Sony’s you have or what earplugs, but if they are good and you enjoy them, I’d say don’t change a winning team.
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