Listened to a lot of subs in the past (none at that level however) and could always feel the sub working separately from speakers. How's the integration in your case, Yuen ?
The proper method to integrate a subwoofer in a stereo system is to use an active crossover like the JL Audio CR1. JL Audio T/S was very helpful in providing the procedure below. Using this type of setup your main speakers and subwoofer will sound as one cohesive unit.
Adjust phase alignment between the main speakers and subwoofer(s):
CR-1; set bypass button off, sub & satellite frequency 80 Hz; crossover slope 24 dB; mute right main speaker
F212v2; set master volume to off; LP filter off; LP frequency doesn’t matter (set on the CR-1); elf trim to 12 o’clock; phase 0.
- Match volume level match left speaker and subwoofer; turn preamp volume to talking level (frequency disc) 75 dB; standing exactly between the left speaker and subwoofer, turn the master level control clockwise until the volume matches the left speaker.
- Set subwoofer phase (polarity) to 180 degrees.
- play frequency disc in repeat for 80 Hz; turn the subwoofer phase control clockwise & then counterclockwise to find the quietest position 80 Hz position.
- turn the polarity back to 0 on the subwoofer and unmute the right speaker on the CR-1.