I've had some similar experience. But fortunately for me I've worked them out more or less. True, an ANC headset will provide quiet, but existing ANC headsets are bulky and about impossible to sleep in for very many hours in a row. My experience goes back to 1982 when I developed tinnitus. I wanted to wear a headset that sent masking sound ("pink noise") to my ears. I found that the ear sound level that suited me was about 35 dBA which was feasible with a battery powered pink noise generator output fed through a high-pass capacitor. That worked just well enough for me to discover an important fact at one point during the wee hours when I awoke. For a half second, I did NOT hear the masking sound... then I did hear it steadily. It was at that point that I knew that our hearing system can be turned off at or by the brain! In retrospect, I remember that our infant sons, after they fell asleep, could picked and held up like a limp rag. Talking did not wake them up. They never were conscious of that. Therefore, being "sound asleep" includes the state of disconnected hearing... In your case of a poor ANC unit, I can only say that of the several I have tried, only the Sennheiser HDC 200-120 ever gave me total silence of the sort we want, especially at very low frequencies... likely down to 20 Hz and less. Regarding fans and vibrations, you have to investigate each separately and determine what part of the fan assembly is at fault. You may have to resort to a different fan type, or more likely to put the fans on a timer that will have them OFF for your key sleeping hours. Coming back ON can be your alarm clock, for instance.
trying to sleep amongst noise
True, an ANC headset will provide quiet, but existing ANC headsets are bulky and about impossible to sleep in for very many hours in a row. My experience goes back to 1982 when I developed tinnitus. I wanted to wear a headset that sent masking sound ("pink noise") to my ears. I found that the ear sound level that suited me was about 35 dBA which was feasible with a battery powered pink noise generator output fed through a high-pass capacitor.
That worked just well enough for me to discover an important fact at one point during the wee hours when I awoke. For a half second, I did NOT hear the masking sound... then I did hear it steadily. It was at that point that I knew that our hearing system can be turned off at or by the brain! In retrospect, I remember that our infant sons, after they fell asleep, could picked and held up like a limp rag. Talking did not wake them up. They never were conscious of that. Therefore, being "sound asleep" includes the state of disconnected hearing...
In your case of a poor ANC unit, I can only say that of the several I have tried, only the Sennheiser HDC 200-120 ever gave me total silence of the sort we want, especially at very low frequencies... likely down to 20 Hz and less.
Regarding fans and vibrations, you have to investigate each separately and determine what part of the fan assembly is at fault. You may have to resort to a different fan type, or more likely to put the fans on a timer that will have them OFF for your key sleeping hours. Coming back ON can be your alarm clock, for instance.