Replacement Module for Vintage Mark
Levinson

It enables to replace DOA018 with LD-2/FET
input amplifier module for LNP-2.

The circuits of 018 are configured the two-
stages of the differential amplifier and the
output stage of push-pull buffer.

The differential amplifier of the first stage is
made up of the dual-FET driven constant
current control.

The dual FET of this stage is the most important
device for giving　high-quality sound.

The dual FET was carefully selected after
listening check over and over again.

The differential amplifier of the second stage
is made up the PNP transistors of matched
pairs.

The current of the class-A operating area is
controlled by this stage.

Usually, the out put stage operates by
complemented NPN and PNP transistors but
we actuate by NPN transistors of the matched
pair.

This is because, it is not symmetry for a pair
of NPN and PNP transistors.

DOA 018 are made up of the finest available
discreet parts and devices which are monolithic
dual FET, matched high quality transistors,

selected mica & polycarbonate film condensers
etc...