Installation; Before Operating The Reference 750 Sel; Vacuum Tube Installation; Vacuum Tube Placement Illustration - Audio Research Reference 750 SEL Manual

Installation

Vacuum Tube Placement

Before operating the Reference 750 SEL

Your Reference 750 SEL amplifier is
shipped with the vacuum tubes packed
in a separate foam-lined carton. These
must be unpacked and installed before
you attempt to operate the amplifier.
Included are one 6H30 input tube, two
KT150 drivers, and 16 KT150 output tubes.
In addition, two power-supply regulator
tubes - one 6H30 and one 6550 - are
located inside on the upper or second-
level circuit board.
Follow the procedure on the next pages
to remove the top cage prior to vacuum
tube installation.
8
001
010
100
011
101
110
111
002
020
200

Vacuum Tube Installation

Carefully remove each vacuum tube from
its protective foam and match its location
'V' number (written on the base of the
tube) to the'V' number screened next
to each socket on the top plate of the
Reference 750 SEL. Firmly seat each tube
in its matching socket, taking care to align
the key at the base of each KT150 to its
socket hole.
To access the internal vacuum tubes, use
the supplied Phillips-head screwdriver
to remove all fastening screws on one
of either of the two side panels; the tube
sockets will be visible near the center of
the board.