Reaper is much louder than Renoise

I rebuild the same tracks (same samples, VSTs, settings) I had in Reaper → in Renoise and Reaper is much louder. No compressors or limiters in either DAW.
Any idea what knobs to tweak?

Check the song headroom settings, I think the default is -6dB


Setting that to 0, raises it to exactly the level of Reaper. Thank you!