Input/Output Connections - Mapletree Line 2B SE User Manual

for the tubes to reach operating temperature ready for use. During operation, is it normal
for the power supply chassis to become warm to the touch.
The power supply is protected by a 1 A/250 V fast-acting fuse located inside the power
supply chassis. Under normal conditions, it should not be necessary to replace the fuse. If
power fails to come on, you can check the fuse and replace with a spare if necessary.
Wait 60 sec with the unit unplugged before removing the bottom cover. If the fuse blows
a second time, you should not try to operate the unit. Contact Mapletree Audio Design for
information regarding service.

Input/Output Connections______

The signal input/output jacks are located on the rear panel of the preamplifier chassis.
RCA jacks are provided for three stereo line inputs, and two stereo line outputs.
Depending on how you ordered your Line 2B SE, the line input gains may be different.
The standard configuration is 10 dB for all inputs. Consult the invoice included with your
shipment to verify the gains for your unit. The upper jacks are the left channel. The line
input impedance (resistance) is normally 100 k? , which provides minimal loading of any
line source such as CD/DVD player, tape deck, tuner, or PC sound card. If one or more
inputs have been configured for other than the 10 dB standard gain, the input impedance
will be affected. See the schematic diagram for details. The line output impedance is less
than 500 ? ? which is suitable for connection to a power amplifier through cables up to 10
ft in length.
The heater voltage switch located next to the power input jack allows you to
accommodate either 12SN7GT (supplied) or 6SN7GT tubes in your Line 2B. Note that
operation in the 12SN7 position with 6SN7 tubes installed will most certainly damage
the tubes.
Line
1
12SN7
1 L R
Out 1
2 3 2
In
6SN7
3