Adjusting Channel Levels - NAD S170iAV Owner's Manual

USING THE S170i
26
ABOUT THE THX MODE
In addition to certifying very high fundamental multichannel audio performance from components
awarded the THX/Ultra logo, THX Ltd's Home THX program also mandates that Ultra components include
the THX mode. This incorporates three fundamental surround-audio enhancements:
• Re-equalization contours high frequencies from the front channels to better match the tonal balance
of the original film soundtrack as reproduced on the "dubbing stage" on which the director and
sound-mixers auditioned the film during its production.
• Timbre-matching compensates for the lateral/rearward placement of surround loudspeakers in a
correctly deployed surround home theater system, achieving a more consistent tonal characteristic
from sounds originating from any point around the audience positions.
• Decorrelation mitigates the monaural surround channel delivered by all Pro Logic recordings (and some
Dolby Digital and DTS sources), yielding more spacious, natural reproduction of a film's ambience and
"virtual acoustics."
ENGAGING THX
From the the HTR 2 remote, press the [AMP] key first, then press the [THX ] key; THX surround will be
engaged. Subsequent presses of the [THX ] key will "toggle" between standard-THX and THX Surround
EX modes (if available) then back to non-THX mode.Note that:
• THX modes are only available to digital-input sources: Dolby Digital; DTS; PCM
• For PCM sources, the Dolby Pro Logic listening mode must previously have been engaged.
• "Incompatible Source" will appear on the OSD and front-panel readout when THX is invoked for an
analog source, when Pro Logic is not the current listening mode, or when THX Surround EX is invoked
for a PCM source or a Dolby Digital or DTS non-discrete-surround source (2/0/0, 2/1/0, 3/1/1, etc.).

ADJUSTING CHANNEL LEVELS

You may make temporary changes to the relative levels of center, surround, and subwoofer outputs
without abandoning the permanent levels calibrated from the OSD's Level setup item. This may prove
useful in a number of circumstances, for example: to increase (or tone down) a film's dialog clarity by
raising (lowering) the center channel; to enhance (or inhibit) subjective ambience from a music recording
reproduced via EARS by raising (lowering) the surround-channels level; to mitigate excessive deep bass (or
enhance deep bass) by lowering (raising) the subwoofer level.
CHANGING CHANNEL LEVELS
From the HTR 2 remote Use the three vertically paired up/down key-pairs, [Surr.]], [Center], and [Sub] to
adjustSurround, Center-channel, or Subwoofer -channels relative levels; the changing levels will be
displayed on the OSD and the front-panel readout.
NOTE THAT:
• Level settings are added to the setup levels established on the S170i preamp's <Levels setup> OSD
menu (above). For example: If your <Level setup> establishes <Center> at "-3 dB" and you manipulate
[Center up/down] level to +2 dB, the net overall effect will be a center-channel level of -1 dB.
• Changes made on the [LEVELS] page are canceled by cycling the S170i through its Standby mode.
• If a Preset was is in force (previously selected), the levels from which [LEVELS] page's three controls
"start" will reflect any levels stored by the preset. (See Configuring Presets, above.)
• The [LEVELS] page will show and permit adjustment of a channel that is not present in the <Speaker
setup> OSD menu. For example: Even if you have set <Center> to "No" on the <Speaker setup> OSD
menu, the [Center up/down] keys will appear on the [LEVELS] page; they will have no effect, even
upon the "phantom center channel" when listening in any of the surround modes.
• If one or two surround-back channels are configured as present in the <Speaker setup> OSD menu,
their levels will be raised and lowered by the [LEVELS] page's [Surr up/down] keys in lockstep with the
surround channels.