Scroll through the preset delay time options and select
the desired time.
When both delays have been entered, choose “SAVE &
EXIT” to save the settings and return to the Main Menu.
In Dolby Digital surround mode, the rear channel delay
time can be set from 0ms to 15ms with 1ms increments.
The center channel can also be delayed up to 5ms, in 1ms
steps.
In Dolby Pro Logic surround mode, the rear channel delay
time can be set from 15ms to 30ms and 1ms per step.
For other modes including DTS, the channel delay time
cannot be adjusted.
Determining Delay Values:
Measure the distance from the listening position to the
center speaker and to one of the front speakers. Subtract
the center channel distance from the front left or right
channel distance. For example, if the front speakers are
12 feet (3.7 m) from the listening position and the center
speaker is 10 feet (3.0 m), the difference is 2 feet (0.6
m). For this example the center channel delay is set to 2
milliseconds or ms.
The GTP-860 can delay the center channel output up to
5 milliseconds and thus compensates for center channel
speakers that are up to 5 feet (1.5 m) closer to the listen-
ing position than the front left and right speakers.
In rare system setups, the center channel speaker is actu-
ally further away than the front left and right speakers.
In these cases, set the center channel delay to 0ms. The
center channel delay time adjustment is only available in
Dolby Digital surround mode.
Now, measure the distance from the listening position to
either the left or right rear speaker. Subtract the rear
speaker distance from the front speaker distance. The
resulting distance is equivalent to the delay in millisec-
onds for the rear delay setting. For example, if your rear
speaker distance is 6 feet (1.8 m) and the front distance
is 12 feet (3.7 m), the correct rear channel delay setting
is 6 milliseconds. Again, set the rear channel delay to 0ms
if the rear channels are further from the listening position
than the front speakers.
3.4 Speaker Settings
Four modes are available to the GTP-860’s setup: On or
Off, and Large or Small.
The On mode is used when the speaker is present. The
Off mode is used when a speaker is not present. Front
speakers are assumed to be present, so they cannot be
turned off. Center, Surround, and Subwoofer speakers are
optional, and these are the speakers you must describe to
the GTP-860. Audio signals intended for speakers which
are not present are redirected to the main speakers.
When a speaker is On, it can be set as Large or Small. The
Large mode is used when the speaker is full range and
capable of reproducing the entire audible frequency spec-
trum from 20Hz to 20kHz. The Small mode is used when
the speaker is not capable of reproducing the deepest
bass portion of the audio frequency 20Hz to 100Hz. When
a speaker is set to small, the low frequencies intended for
that speaker are redirected either to the Front speakers
or the Subwoofer.
For best results, you should consider using a center
speaker. Ideally it should be the same type as the left and
right speakers. Using a separate center channel speaker
will allow the dialogue to cut through even the biggest
sound effects and musical scores. Having the sound spread
across three front speakers also stabilizes the stereo
image, making the usable listening area much bigger.
Installing surround speakers will greatly enhance the sur-
round experience as these add considerably to the overall
“ambiance.” Dolby Pro Logic encoded material is deliber-
28 | ADCOM GTP-860 OWNER’S MANUAL
surround
rear left
surround
rear right
front left
front right
center
surround
back right
surround
back left