Anthony Gallo Reference 3 S.A. Amp - Manual (Page 3)

Where do I set the crossover control which is continuously adjustable from 40-200Hz?
Remember that the natural acoustical roll-off of our Ref³ woofer occurs at approximately 40Hz. It still
reproduces sounds as low as 20Hz but those are significantly reduced in output and thus barely audible. To boost
those rolled-off frequencies in the lowest octave, you probably don’t want to set the SA crossover much higher
than 40Hz. This avoids undue overlap and excessive warmth or bass heaviness. However, the exact amount of
perfect fill-in is also a function of room size and how far away from the rear wall you have positioned the speakers.
The farther into the room you pull the speakers, the less boundary reinforcement support they receive. But the
farther you pull them into the room, the more spectacularly they will soundstage.
Conventionally, full-range speaker positioning always revolves around this compromise, between the best
(fullest and most linear) bass response on the one hand and the best disappearance act of ‘just sound and no
speakers’ on the other. With the Reference3s and the matching SA, this common compromise ends once and for
all. Whatever bass slam, impact and weight you will sacrifice in the best soundstaging position can be added back
by the SA. Not only that, you can extend bass reach below what the Reference³ will produce even in the most
optimal ‘bass position’ of your room.
That’s why the SA offers crossover points above 40Hz. It accounts for variables of rooms, setups and
personal preferences. Simply adjust the crossover control by ear and to taste and start with the lowest possible
setting at 40Hz.