Planning to run this setup for nSPL Finals this weekend... needed to stay under 5000 watts on the nSPL clamp meters. On my meter it clamped exactly 4000 watts last night which should be 4700-5000 on their clamps. Tuning is in the high 30s and peaks at 47 Hz... tuned to 30 Hz and also peaking at 47 Hz it was about 1.8 dB quieter but still not bad at all, IMO. I plan to try cutting the ports down a bit more to see if I can get a tad more from it on the meter... may or may not get that done before