Bag End’s newest generation of bass signalprocessors—the INFRA-MX2—offers numerous new features,including improved grounding scheme, use of surface-mount technology,included improved power supply with improved error tolerance, able toproduce a flat response down to 8 Hz and an improved graphicdesign.
The dual-processor technology operates a subwoofer below resonancewithout the use of lowpass filters, eliminating filter delay, impedancebumps and other irregularities. In the INFRA technology, the electricalsignal goes through the INFRA electronics before the power amplifier,as it would with a conventional electronic crossover. Inside the INFRAelectronics, a slope is applied to the signal by the use of dualintegrators lifting the low frequencies by 12 dB per octave.
The INFRA loudspeaker is placed in a small enclosure providing arelatively high system resonance for a subwoofer. The system’s responsewithout the INFRA electronic drive will rise at 12 dB per octave up toits resonance frequency and then flatten out until the woofer reachesits upper limit. When INFRA drive is applied, the 12 dB per octaveroll-off of the cabinet combines with the 12dB per octave lift of theelectronics to form a flat frequency response down to the lowest pointset on the INFRA electronics, which can be as low at 8 Hz. Aboveresonance, the loudspeaker would normally respond flat up into themidrange. With INFRA drive, the dual integrators roll-off at 12 dB peroctave from the system resonance or the point where the speaker wouldnormally run out flat.
There are no lowpass filters in INFRA technology. Therefore, thereis no filter delay. Below resonance, the impedance, cone excursion anddampening factor are uniform and predictable. Thus, the reaction time,controllability and the ultimate fidelity of the loudspeaker areimproved. The spatial offset between the INFRA system and theupper-range loudspeakers is minimized, providing a seamless match.
“The result is a conveniently sized subwoofer with a highly musicaland precise extended low-frequency capability,” commented James P.Wischmeyer, Bag End president. “To boil it all down to one concisephrase, INFRA technology makes a bass system simpler, smallerand—at the same time—makes it sound better.”