Heya,
there's a couple of threads asking about safe listening levels and people asking about voltage/power requirements in almost any amp/headphone thread.
Here's my take on this:
Noise Exposure Limits
The EPA and WHO recommend that noise should be kept below 70 dBA over 24 hours and below 75...
Say there is a device that supplies ~54v of phantom power instead of the conventional 48v.
If one plugs Cloudlifter, FetHead, etc. into the chain, can these be damaged by the excess voltage?