While indeed the Welti/Harman approach is aimed at a larger sweet spot, it does not preclude the possibility of improvement in the sweet spot gained...
Hi Steve,
My suggestion had nothing to do with adding more bass, but to deal with the dramatic response swings for which you are seeking relief with...
Screen
106” diag 16:9 Da-Lite Tensioned Advantage Electrol, High Contrast Cinema Vision surface, 22” total drop, SCB-200 and IR-200 remote.
42-deg view to front row
30-deg to rear row
Speakers
L/R Aerial 7B
C Aerial CC3B
4 surrounds B&W CWM-8180 inwalls in custom back boxes
Sub Hsu ULS-15 Quad Pack
Projector
JVC DLA-RS10
Amplifiers
Classe CA-201 for L/R (200w/ch)
Classe CAV-150 for C and 4 surrounds (150w/ch)
AV processor: Classe SSP-800
Bass processor: JBL BassQ
DVR/OTA tuner: DirecTV HR21/AM21
Blu-ray / DVD player: Oppo BDP-83
CD player: Sony CDP-X55