Front Panel Controls; Tubes; Care Of Your Line 2 - Mapletree Line 2C User Manual

Stereo line preamplifier, power supply

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Front Panel Controls

Line 2 C Pr e a mpli fie r

The front panel controls are (left to right) the 3-position Source selector switch (Line1-

Line2-Line3), Mode switch (Stereo or HT), Volume control, and Balance control. In HT

mode, the selected input source is connected to the output jacks and the active preamp

output is disabled; the power may be turned off.

The tubes supplied are new-old stock (NOS) and have been pre-tested. A burn-in period

of several hours may be needed to achieve the best sonic performance. Tube life should

be thousands of hours. Aging tubes may result in a reduced gain in one or both channels

or an increase in noise levels. Infrequently, a heater may burn out which is indicated by

total loss of sound. Replacement tubes can be obtained from several suppliers in the U.S.

and Canada. Some listeners enjoy trying different brands and variants of tubes. The

heater voltage selector switch permits the use of 6SN7GTB (or the 5692 special red

version) tubes of NOS or current manufacture. The highly regarded 12SX7GT is

equivalent to the 12SN7GT.

The chassis finish is lacquer-based and, while hard (and continues to harden over time), is subject

to chipping on impact with another object. Both the chassis and labels/logos are moisture resistant

but you should avoid cleaning with water, alcohol, or other strong chemical. A soft 1" paintbrush

is recommended to dust the chassis periodically.

Heat is the most troublesome enemy of electronic components, especially capacitors. Heat can be

properly dissipated by ensuring free air circulation around the preamp and power supply chassis.

It is not recommended that you leave the power on when not in use.

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