Oh, if you want to hear what they sound like, try simplynoise.com on a low setting. I prefer the brown/​red setting, which is quite similar to the noise the machines make (at least on the setting I use).
Oh, if you want to hear what they sound like, try simplynoise.com on a low setting. I prefer the brown/​red setting, which is quite similar to the noise the machines make (at least on the setting I use).