Thermionic Culture THE FREEBIRD 3 channel equalizer - Manual (Page 6)

©Thermionic Culture Ltd., May 2011 5
3 Circuit Design
The design of The Freebird was also initially based around
the type of valve selected.
We felt that the simple single ended design particularly
suited this unit and that the input 5965 valve combined with a
PC86 output valve, gave a very desirable quality to the
sound of the unit.
An input transformer was added to counteract potential
problems that might be found with certain combinations of
electronically balanced equipment. The output was left
unbalanced because we love the 'open' sound this gives the
unit.