Does Reaper have a built-in limiter on the master bus?

And if so (which it sounds like it does) what is there to be known about it? If I put a JS Volume Adjust on the master bus, it seems to override the limiter that's built in (probably because JS is getting clipped) but without it, the sound is clean and unclipped, albeit with a some slightly audible compression/limiting.

I think by default it's set to +18dBFSD just to prevent monitor damage if you accidentally create a feedback loop. It mutes the output rather than "limits"... Edit: if you're hearing limiting, maybe you've something in your interface catching the overs. What are you using? REAPER uses floating-point maths, so won't clip, but fixed-point audio interfaces receiving the audio feed will, unless they have some mechanism to counter it... >

No it does not. Why would it? o.O