Nine long recordings, each on its own page with the timer beside it. Pick by what you need to cover, then by ear.
A free brown noise player with a focus timer in the same tab.
PlayA free white noise player with a built-in focus timer.
PlayA long rain recording, not a loop, with a focus timer in the same tab.
PlayCafé ambience with a focus timer in the same tab.
PlayBirdsong and leaves with a focus timer.
PlayCrackling fire with a focus timer.
PlayWaves on a shore with a built-in timer.
PlaySteady wind with a focus timer in the same tab.
PlayA waterfall with a focus timer.
PlayNot sure which colour of noise? Read brown noise, white noise, or pink noise.