6-1
DFP-3000
6. B-Chain Alignment
B-Chain alignment is performed using the DFP-D3000, Setup Software, and your own test equipment. To
begin, connect your computer to the Decoder using a null modem cable, launch the Setup Software, and
“connect” the Setup Software to the DFP-D3000 using the Config>Connect to DFP… menus. Set up
your microphones and analyzer (THX R2 or other multichannel real time analyzer) in the theatre. Refer to
SMPTE Standard 202M, B-Chain Electroacoustic Response, for more detailed information on micro-
phone placement, theatre acoustics, and the “X” curve. Note that the DFP-D3000 must be set up with the
Master Fader nominally set to 0.0 (not 7) and that from this position 10 dB of boost and full cut is
available, with an audio/dB fader taper.
6.1 Open the Master DFP-3K Settings screen by select-
ing Master DFP-D3000 under the Master option in
the main screen menu bar.
6.2 Ensure that the Master Volume is set to 0.0 dB. Select
the appropriate output level for the DFP-D3000; this is
the absolute signal level that corresponds to the _20
dBFS reference point. In most cases you should chose
_10 dBu (145 mV).
Use your real time analyzer (RTA) to check the SPL in
the theatre and ensure that it is in the right range when
the Master Volume is 0.0 dB.
6.3a Move all Channel Level Trims to the center
setting (0.0 dB). Center all equalizer sliders at
0.0 dB. To quickly set all EQ levels to 0.0 dB,
access the Reset Channel function in the Tools
pull-down menu located in the main screen menu
bar. The illustration shows the main screen of the
Setup Software in this condition, for the Left
output channel.