@mkgus, Rythmik provides very detailed information about phase and loudspeaker/subwoofer integration on the company website (rythmikaudio.com). The Rythmik A370 and H600 lines of plate amps include a "PHASE/DELAY" continuously variable knob control, providing 0 to 180 degrees of adjustment. Put in terms of time, that is zero to 16 milliseconds of delay. As sound travels roughly 1 ft. per millisecond, setting the control at 1ms in effect electronically moves the subwoofer back one foot. The control is not able to move a sub forward in time, of course! If you set the control to 180 degrees, you have just inverted the phase of the sub (which is all a 0/180 phase ’switch" is able to do, greatly limiting a users ability to integrate speaker and sub).
The Rythmik website page on integration explains in very understandable terms (with examples) how sealed versus ported speakers and subs can have their outputs put in phase via the use of the excellent Rythmik controls (which also include an EXTENSION FILTER providing three degrees of damping---low, medium, and high---at three different frequencies---14Hz, 20Hz, and 28 Hz, a CROSSOVER continuously variable from 25Hz to 120Hz, a single band PEQ control with variable bandwidth, frequency---20Hz to 80Hz, and level---+3dB to -12dB controls, a LIMITER on/off switch, and a RUMBLE FILTER).
Even if you choose a sub from a company other than Rythmik, the information provided on the website’s technical pages should assist you in your efforts to integrate any sub with any speaker. Gee, I wonder if I will now get chastised for "pimping" for Rythmik ;-).
