Caledonian Audio Phono Classique, Assembly Manual

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You have now successfully completed the power supply PCB.
2.2 Phono preamp PCB
The phono PCB is the main part of the audio amplification system. It handles
both left and right audio channel.
The PCB has been designed in such a way that that all components (apart from
the valve holders) can be mounted in either side of the board. This enables
builders to choose which PCB mounting configuration to use (e.g. valves
sticking out from the case OR valves and PCB stay inside a case).
However, in this manual, we will be mounting the components on the normal
silkscreen components side, which enables us to mount the PCB in such a way
that the valves will be protruded outside the case (check the front-page picture).
2.2.1 Valve Holders
On the “VALVE SOCKET SIDE” of the PCB, place and solder the valve/tube
socket.
Ensure that the valve socket is sitting correctly and leveled with the PCB. It is
important to sit the socket correctly (the axis of the socket and PCB are parallel)
as this will determine the angle of the valve when it is inserted.
HINTS: Put a small amount solder on only one of the socket feet first and check
and make sure that all others are sat correctly. Only proceed with soldering
others once you are 100% sure that the base is correctly placed.