Adcom GTP-600 - Manual (Page 16)

D) The test tone will shift to the rear speakers. Use the “Rear Level Up” and “Rear Level Down” buttons © to
adjust rear channel output to match that of the front left, center, and front right speakers.
You'll probably need to let the Balance Check test tones cycle through all speakers three or four times until you've
matched levels closely. Don't worry about how fast you can accomplish this balance adjustment — just take your
time and do it carefully.
NOTE: DO NOT PLAY ANY OTHER SOURCE THROUGH THE GTP-600 WHEN USING THE BALANCE CHECK
CIRCUIT; if you need to check balances when playing a source, simply put the source on “Pause,” go through the
balance check routine, then resume playing the source.
27) SURROUND and DELAY CHOICES;
The GTP-600 is an enormously flexible unit. This section is the most subjective in the entire Owner’s Manual: Feel
free to take the suggestions here as starting points for your own experimentation. Above all, enjoy!
A) Choosing the proper operating mode:
The GTP-600 provides seven operating modes selected by the “Surround" button on the front panel © or the
remote controller e These are: Cinema, Dolby Pro Logic, Stadium, Concert Hall, Nightclub, 5 channel
stereo, and Bypass (2 channel stereo.) Each of the first six modes is indicated by a front panel LED. (The
Cinema mode displays two LEDs — one to the left of “Cinema" and the second to the left of “Dolby Pro
Logic.”) In Bypass, or 2 channel stereo, no Mode LED lights.
1) CINEMA: This ADCOM circuit enhances the dimensional accuracy of Dolby Pro Logic decoding with
proprietary signal processing techniques to more closely approximate the acoustical soundfield of a
large movie theater.
A shelving filter with a corner frequency of 7 kHz reduces the often excessive high frequencies that make
some video soundtracks fatiguing to listen to. In addition, Cinema mode adds diminishing multiple delays
through the rear speakers to diffuse the surround information even further than is possible through Dolby
Pro Logic.
Left & right front output: enhanced Pro Logic matrix
Center channel; Yes
Initial rear delay setting; 30 milliseconds
Additional delay choice: 20 milliseconds
2) DOLBY PRO LOGIC is one of the two preferred modes for properly processing Dolby Surround”^ encoded
video soundtracks, a growing number of CDs, and even the audio portion of some computer games!; In
this mode, the GTP-600 presents a spatially correct soundstage with precise lateral imaging and front to
back depth.
Left & right front output: Pro Logic matrix
Center channel output; Yes
Initial delay setting; 20 milliseconds
Additional delay choices; 30 & 15 milliseconds
3) STADIUM is used for non-Dolby Surround encoded material and recreates a large and acoustically
reverberant environment well suited for video sporting events and playback of music that is usually
performed in large outdoor arenas. A slight upper midrange frequency emphasis is added to the front
channels to enhance intelligibility. STADIUM mode is also well suited for playback of older epic movies
with mono soundtracks.
Left & right front output: Wide matrix
Center channel output: No
Initial delay setting: 75 milliseconds
Additional delay choices: 100 & 50 milliseconds
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