Sony STR-ZA810ES Manual page 121

Select [Setup] - [Zone Settings] from the home menu.
1
Select [Zone2 Line Out].
2
Select the setting you want.
3
Variable:
Recommended when using another amplifier that does not have volume control for
Zone 2.
The volume for the AUDIO ZONE 2 OUT jacks can be changed.
Fixed:
Recommended when using another amplifier with variable volume control for Zone 2.
The volume for the AUDIO ZONE 2 OUT jacks is fixed.
Note
When [Variable] is set, the volume is turned down by default. Turn up the volume while listening to
the sound after completing setup. The volume for the SPEAKERS ZONE 2 terminals is changed
together with the volume for the AUDIO ZONE 2 OUT jacks.
[121] Using the Multi-Zone Features
Enjoying sound using another amplifier in Zone 2
You can enjoy sound from another amplifier in Zone 2 by the following procedure.
Select [Zone Controls] - [Zone2 Power] - [On] from the home menu.
1
Zone 2 is activated.
Turn on the amplifier in Zone 2.
2
Select the source signals you want to output in the [Zone2 Input].
3
Select [SOURCE] if you want to listen to the same sound as main zone in Zone 2.
Start playback on the input that you selected in step 3.
4
Adjust to a suitable volume.
5
Adjust the volume using the amplifier in Zone 2. If you set [Zone2 Line Out] to [Variable],
you can also adjust the volume in Zone 2 using [Zone Controls] - [Zone2 Volume] from the
home menu.
Enjoying sound in two rooms using another amplifier