ive always had this idea, having done most drugs(street/rc) other than coke/crack/pcp/meth(tho done many amps and ket/methoxetamine), that crack is very similar to a stimulant nitrous rush. i dont know really, but most descriptions of crack mirror my times on n2o. sept obviously not a stimulant.
and the ringing... i chase the happy dmt land like pure euphoric ear ringing state you fall into when u close your eyes with a bit hit of n2o.
any comparison from someone who has done both many times?
edit: i also once got a horrid dysphoric effect from a non tryptamine non beta carb isolate of mimosa(could have been dissolved plastic for all i know, it was insoluble in everything it was originally dissolved in) 5mg of it gave a stupid strong headrush/pressure with ringing and this sick feeling like my skull was going to explode combined with the exact effect shown in the episode of southpark where mr mackey takes lsd. head floating, necktie tightening, head blowing up like a balloon. leads me to believe the thing about inner ear pressure.