Sony Ericsson DFP-D3000 - Manual (Page 24)

6-4 DFP-3000
40 63 100 160 250 400 630 1K 1.6K 2.5K 4K 6.3K 10K 16K
Center channel loudspeaker response
40 63 100 160 250 400 630 1K 1.6K 2.5K 4K 6.3K 10K 16K
Analog subwoofer channel response
Same SPL
6.8 To set the equalization for the subwoofer loudspeaker, press
F6 to select the Subwoofer output channel and bring up the
2-band parametric equalizer. Verify that sound is coming
from the subwoofer loudspeaker cabinet.
Purists may want to set the optical subwoofer level by playing a pink noise loop and adjusting to
make the overall response of the screen speakers as flat and extended as possible as a result of the
subwoofer’s supplementation. This technique is beyond the scope of this Guide.
Recognize that the SDDS (and other digital formats’) subwoofer is an effects channel that delivers
low frequency sounds that are designed to enhance certain elements of a particular film. The analog
subwoofer is derived from the optical L,C,R channels and is intended to compensate for limitations
of the screen speakers being used; modern, full-range screen loudspeakers may need little or no
analog subwoofer supplementation. For a longer discussion, see Tech Note TN99051701.
The low pass filter frequency for the optical preset must first be set to match the response of the
subwoofer to the response of the screen speakers. Wide range screen speakers can have the optical
subwoofer low pass filter set to the lowest value of 80 Hz; 100 Hz is a good starting point for most
modern screen loudspeakers.
What ever method is used, a final listening test, using film having a high quality optical track with
familiar, wide range content should be auditioned to ensure that the subwoofer level is set for best
sound and optimal low frequency balance. If you use a non-sync audio source, such as a music CD,
for this test, be sure to select Mode 6, 7, 8, or 9 for your non-sync Preset in the Preset Configuration
screen (see Step 6.11), so that the analog subwoofer output is active.
Adjusting the subwoofer equalizer is especially difficult and benefits from experience with the
particular cabinet model used. Use as little EQ as possible and allow your RTA display extra time to
settle between adjustments. Aim for a smooth, rather than extended, response. Note that the higher
frequencies are rolled off by the subwoofer low pass filter, whose frequency is shown below the
graphic display and is indicated by the vertical yellow line. Use 330 Hz for this step and reduce the
setting later, using separate settings for optical, digital, and other presets.
The analog subwoofer channel level trim affects the subwoofer output level of all eight presets. The
SDDS subwoofer level is an offset trim from this value. The AUX subwoofer offset settings are also
offset from the analog subwoofer channel level trim.
6.9 The recommended method of setting the analog subwoofer level is to use the internal pink noise
generator as you have previously done for the screen speakers and adjust the subwoofer power
amplifier input gain control and the subwoofer level trim (which is essentially in series with the
subwoofer power amplifier’s input gain control) to make the subwoofer’s RTA bands match the level
of the Center channel’s RTA bands where they are flat. Use attenuation in preference to gain at the
subwoofer level trim and achieve gain with the subwoofer power amplifier’s input control. When you
make a change to the Analog Channel Level Trim slider while the Subwoofer output channel is
selected, the software will automatically select a non-SDDS Preset.