©
Thermionic Culture Ltd August 2014
7
3
Controls and Operation - Preamp A and B
3.1 Input
Level
This 3 way switch at the top of each preamp section
allows the user to run the preamp as a Line input, Hi
mic. level input or Lo mic. level input.
3.2 Gain
The rotary gain control is located at the top of each
preamp section. It allows the channel signal to be
attenuated at the input continuously. This gives a
channel gain between:-
-
∞
to + 5 dB gain for the Line amp
-
∞
to + 21 dB gain for the Hi mic. setting
-
∞
to + 34 dB gain for the Lo mic. setting
3.3 Top
The rotary control allows the amount of top lift EQ to
be continuously adjusted between 0 and +12 dB. The
EQ starts as a gentle type curve and it reaches it’s
peak at 9.5 kHz.
3.4 Pres
The rotary control allows the amount of mid lift EQ to
be continuously adjusted from 0 to +11dB with a very
broad curve peaking at 2.8kHz.
3.5 Bass
The rotary control allows the amount of bass lift EQ to
be continuously adjusted between 0 and +11 dB. The
EQ has a 'varislope' type curve which is initially very
broad, reaching a small peak at 90Hz at a position of
'5' and then reaches it’s final peak at 40Hz when the
control is turned on full.
