i'd be willing to bet money, you gain a lot of loudness and sound quality swapping over to an audiopipe apcl 1800.
I owned two BRX 2400, sh*t amps compared most of the stuff out there. supposedly 4800 watts total or more like 4000 since its "overrated"
However even against a DC 3.5k, which is only 3.5k certified on the amp dyno, that DC absolutely destroyed the other two in both loudness and sound quality. the BRX even with no subsonic filter, didnt play anything under 30hz well at all. the DC got me playing down to low 20s and at least several dbs louder than the two.
Another run in with hifonics is my buddy's explorer which we tested a hifonics brutus 2200 vs an audiopipe apcl 1500. Same fking issue with the hifonics needing high gain, not playing lows, and overall not that loud. The audiopipe at 1/5 gain was already louder than the hifonics at 75% even with full 4 volt pre-out. The audiopipe played down to low 20s easily while the hifonics was cutting off at 29hz. Box was tuned to 28hz. WTF is that sh*t