Speaker Levels - NAD M15 HD Owner's Manual

Speaker Configuration can be managed and adjusted by pressing a
combination of and then keys. Set 'Front, ' 'Center, ' and 'Surround' to
"Large, " "Small" or "Off" as your subsystem's speakers require.
The 'Back' speakers can either be one or two speakers. Set 'Back' to either 1
or 2 speakers as per availability. Set 'Subwoofer' to "On" or "Off, " selecting "On"
only if you have a subwoofer connected to the M15 HD's SUBW1 or SUBW2
output jack.
ENHANCED BASS
When the subwoofer is set to ON and "Front" is set to "Large", Enhanced
Bass is also available. Normally, with speakers set to "Large" the subwoofer
is not active. The Enhanced Bass option allows full range operation of
the speakers with the additional bass contribution of the subwoofer. This
feature is particularly useful when one wants to experience maximum
bass output. Please note that due to acoustic cancellation effects, the bass
response may be uneven when using this setting
You can set Subwoofer to "On" even with "Large" front speakers, in which
case bass content from any channels set to "Small" will be routed to both
the subwoofer and to the front speakers; LFE-channel signal will pass only
to the sub. In most subwoofer-equipped systems, setting front speakers to
"Small" is usually the better option.
All the speakers' low frequency content can be directly adjusted within the
range 40Hz to 200Hz.
NOTE
The configurations set forth at 'Speaker Setup' are carried over whenever
it is enabled during A/V Preset setting. Please see also the section 'AV
Presets' for reference.

SPEAKER LEVELS

Adjusting the relative balance of your system' s loudspeakers ensures that
surround-sound recordings, whether music or film, will present the balance of
effects, music, and dialog that the artists intended. Additionally, if your system
incorporates a subwoofer it establishes a correct relationship between the
volume of the subwoofer and the other speakers, and thus of low-frequencies
(bass) to other sonic elements.
USING AN SPL METER
It is quite practical to perform the M15 HD level setup routines "by ear, " and
careful work will produce acceptably accurate results. However, the use
of an inexpensive sound-pressure level (SPL) meter, such as Radio Shack
part number 33-2050, makes this task easier, more accurate and more
repeatable. Ownership of such a meter could prove a valuable audio tool.
USING THE M15 HD – SETUP MENU
The SPL meter should be placed at the primary listening position, at
approximately the height of the seated listener's head. A tripod is helpful
but with a little duct tape almost anything — a pole lamp, music-stand,
or ladder-backed chair, for example — can do as well. just be sure that no
large acoustically reflective surfaces obstruct or are near the microphone
element.
Orient the meter with its microphone (usually at one end) pointing straight
up toward the ceiling (not toward the speakers) and ensure that "C"
weighting scale is selected. Set the meter to display 75 dB SPL. On Radio
Shack meters, this necessitates either setting the meter to its 80 dB range
and taking your readings at the -5 point or selecting the 70 dB range and
reading at the +5 point.
SETTING SPEAKER LEVELS AT TEST MODE
While at 'Speaker Levels' menu, press the HTRM remote's 'Test' key activating
the M15 HD's Speaker Levels balancing test signal . You will hear a "surf"
sound as you step through your speakers ('test' appears to the right side of
the current speaker), beginning with the Front Left. If you do not hear the
test signal, check your speaker connections or your 'Speaker Setup' OSD
menu settings.
Use the remote's keys to adjust the loudness of the noise output from
the currently playing channel to the required level (it's usually simplest to
begin with the Front Left). As you cycle the test signal around the speakers,
the OSD will highlight the currently playing channel. The "level offset"
reading on the right will change by 1 dB increments; ±12 dB adjustment is
available. Press 'ENTER' to adjust the next speaker.
NOTE
If you are balancing levels "by ear", choose one speaker—usually the
center—as a reference and adjust each of the others in turn to "sound as
loud" as the reference. Be sure that you remain in the primary listening
position while balancing all channels.
To produce the same SPL meter reading (or subjective loudness), use the remote' s
keys to adjust each speaker.
NOTES
• All speakers must be in their final locations before level-setting.
• Your subwoofer (if any) should be set with its integral crossover defeated,
or if undefeatable, set to its highest-possible frequency if you are using
the M15 HD's Subwoofer output. Final subwoofer-level adjustment "by-
ear, " using music and film sound material, is frequently useful.
• Due to the effects of room acoustics, matched-pair speakers (front;
surround; back) will not always calibrate to exactly the same level offset
readings.
You can exit 'Test' mode at any time by pressing
'Speaker Setup' menu. You can also press the 'TEST' key to discontinue the
'Test' mode.
OPERATION
key, bringing you back to
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