Adcom GTP-880 Channel Configuration Calibration, To set the channel levels for you system

this will insure that all the appropriate low frequency information is directed to the subwoofer where it can be most effectively handled.

4.Use the and buttons to cycle through the speaker options for the front speaker. The following options are available for each group of loudspeakers:

•For front you can select small or large

•For center you can select small, large or none

•For surr(ounds) you can select small, large or none

•For surr(ounds) rear you can select BS(LB), LB/RB or none. LB/RB means you have a left back and right back rear surround speaker setup for use in a 7.1 configuration. BS(LB) means you have a single centrally placed back sur- round speaker for use in a 6.1 (EX) type configuration.

•For subwoofer you can select on or off

5.Press the button when you have made a selection. Repeat steps 4 and 5 until you have completed selecting the speaker type for each loudspeaker in your system.

6.Press the button when you are finished to select

the front crossover (xover) menu. The front, center and surround crossover menus are used to independently set the internal high pass filter of the GTP-880’s crossover for each of these three speaker groups.

7.Use the and buttons to adjust the front crossover. The crossover settings appear as follows as you scroll through them: 40Hz, 60Hz, 80Hz, 100Hz, 120Hz, 150Hz

Note: None will appear for a large speaker setting.

You can scroll in either direction using the and buttons.

Consult the material that came with your loudspeakers to determine the correct settings, if any are recommended. If you are not sure about the frequency response of your speakers, we recommend you set the crossover at 80Hz, unless otherwise directed by the manufacturer. If you are using very small satellite speakers you may need to set the crossovers to 100 or even 120Hz. When correctly set, you should hear a smooth transition of lower to upper bass between the satellites and the subwoofer.

8.Press the button when you have made a selection. Repeat steps 7 and 8 until you have completed the speaker crossover settings for each group of speakers.

9.Press the button to select the return to main menu option.

10.Press select or menu to return to the main menu, or press the menu button twice to exit the menu system.

3.5 Channel Configuration: Calibration

The next step is to adjust the output level of each channel so that they are properly matched. This must be done

to insure a correct presentation of multichannel sound sources. The adjustment must be as precise as possible, and is almost impossible to accomplish by ear. Therefore, we recommend that you use a sound level meter. This device insures that all loudspeaker levels are precisely matched and set accurately. (The Radio Shack analog sound level meter is inexpensive and suitable for this task.)

Set the meter to slow response and “C” weighting. Set it to the 70 or 80dB sensitivity scale. Position the meter at the approximate center of your listening area, at average ear height [approximately 40-46 inches (102-117 cm)] with its microphone positioned vertically (pointing at the ceil- ing). Don’t aim the microphone at the speakers, as this will produce inaccurate results.

To proceed with the adjustments, you will access the channel calibration menu shown below.

To set the channel levels for you system:

With no source playing, set the volume level of the GTP-880, using the main volume control, to 0dB.

1.Press the menu button to enter the main menu. The main menu appears on the front panel display and the OSD. The cursor on the OSD should be pointing to the input configuration menu and input config appears on the front panel display.

2.Press the button until the channel calibration menu is selected. The cursor on the OSD should be pointing to the channel calibration menu and channel calib appears on the front panel display.

ADCOM GTP-880 Owner’s Manual 39