Sony G90 …the controller represents, Radical new path to, Future…, High-Resolution Digital Audio

speaker systems. For example, if you have five			Keeping low bass out of smaller loudspeak-
small loudspeakers and a subwoofer, you tell			ers confers large advantages in the speaker’s
the controller to filter bass from each of the			power handling, dynamic range, midrange clari-
five channels, and to direct it, in sum, to the			ty, and sense of ease. When the woofer doesn’t
subwoofer. When watching a Dolby Digital or			have to move back and forth a long distance try-
DTS movie, the bass from the LCR and sur-			ing to reproduce low bass, the midrange sounds
round channels is mixed with the Low Fre-			cleaner and the speaker can reproduce louder
quency Effects channel to drive the subwoofer.			peaks without distortion.
The bass management in most controllers lets you			High-Resolution Digital Audio
direct the full frequency range to the left and right channels
(including the LFE channel), but filter bass from the center			Decoding
and surround channels.			Many controllers today feature the ability to accept digital
A feature in the most advanced controllers is the ability			input signals with a sampling frequency of 96 kHz and word
to specify the crossover frequency and slopes between the			lengths of up to 24 bits. This allows them to decode high-res-
subwoofer and main speakers. The crossover is implement-			olution digital audio output from a DVD player that can
ed in the digital domain with DSP. Splitting the frequency			deliver 24/96 digital signals (the Pioneer DV-09 is an exam-
spectrum into bass and treble in the controller is a vastly			ple). The selection of 24/96 discs is slim, and until a digital
better approach than subject-				interface with a copy-protec-
		…the controller represents
ing the analog audio signal to				tion system is in place, don’t
the capacitors, resistors, and		a radical new path to		expect many DVD players to
inductors found in the cross-				provide access to the 24/96
overs	built into subwoofers.	the future…		bitstream.
Other	controllers let you			A more useful feature for
specify the crossover frequency (40 Hz, 80 Hz, 120 Hz, for			taking advantage of the high-resolution multi-channel for-
example), but not the slope or phase characteristics. The			mats about to come on the market (DVD-Audio and Super
greater the flexibility in this function, the greater the likeli-			Audio CD – SACD) is a six-channel analog input on the con-
hood that you can achieve the best results with your speak-			troller. Until the digital-interface issue is resolved (which
ers and room.			may take a long time because it is inextricably linked to the