true peak and what to do

So the cheapest car stereos could be an example of a worst case DAC? Something with no headroom? I’m actually looking for something like that to hear the effect. Maybe the cheapest portable player? I’ve heard the DAC in the iPod is pretty respectable (and I would assume has some headroom), so I would think I’m looking for something quite a bit worse than that. If anyone knows of anything that definitely has no headroom…