Unlike any other speaker or amplifier manufacturer, Bose refuses to publish any frequency response charts or distortion data on their products (and with good reason). And thus a few independent audiophiles, industry professionals, and newsgroups have taken it upon themselves to benchmark test the much debated Acoustimass system. The resulting numbers are always consistent. Here is a pretty credible one sourced from the August 1999 issue of Sound and Vision magazine...
SATELLITES BASS MODULE
Frequency Response 280 Hz to 13.3k Hz at ±10.5 dB 46Hz to 202Hz at ±2.3 dB
Sensitivity (SPL at 1 meter)* 85.1 dB N/A
Impedance (minimum/nominal) 5.3/8 ohms N/A
Bass Limits (-3/-6 dB) 280/220 Hz 46/40 Hz
* measured with 2.8 volts of pink-noise input
To reiterate the above, the Acoustimass's bass module responds to 46 Hz to 202 Hz at ±2.3 dB, while the satellites respond to 280 Hz to 13.3 KHz at ±10.5 dB. This is, by the way, the only speaker that I have ever seen tested with a ±10.5 db allowance. Still, this leaves a frequency gap between the satellites and bass module of about 80 Hz! That is 80 hertz of sound that is completely erased within the system's internal crossovers