VAC Phi 2.0 Master Control Preamplifier User Manual

Page 13

REPLACEMENT OF LOW LEVEL TUBES

Tubes V1L and V1R are 12AX7/ECC83;
you may wish to use low noise tested
tubes.

Tubes V2L, V2R, V3L, and V3R
are12AX7/ECC83.

Tubes V4L and V4R are type 8416, no
substitute types are acceptable.

We strongly recommend that you use
only tubes specifically selected and
tested by VAC for this application.

Before replacing tubes, all power must
be turned off. Allow 15 minutes for the
tubes to cool down before removing
the top glass cover - in use they
become hot enough to cause burns.

Install new tubes of the appropriate types firmly in their sockets, noting the location of holes
in the socket and pins of the tubes, taking care to make sure that pin pattern corresponds
to holes in tube socket. Replace the glass cover before operating the preamplifier.

In the event that trouble is encountered, check all signal, speaker and power connections.
If the problem persists, follow all safety precautions stated earlier in this section, and check
that all tubes are correctly seated in their sockets. If possible, try another tube. If the problem
persists, please consult your VAC dealer or contact the factory directly.

Tubes are like the tires on a car; they will eventually need replacement. Murphy's Law states
that a tube will probably fail right at the start of a long holiday weekend. Therefore, many
audiophiles keep a spare tube of each type on hand, just in case!

VAC can test tubes for concerned customers.