Putting
together a one-off Transformer Balanced Variable Diode
colour/saturation box. Massive high level 600 ohm to 600 ohm 1:1
transformers that came from a vintage Decca Broadcast unit. 

They are
too big to go inside the box so some mods done to house them and still
look great! 

These were used as a balanced line output for the main
signal. A very high build quality MU-Metal transformer than was
probably made for them by Sowter... Around a 30dB level without
saturating so would be perfect for a cleaner less coloured sound but
then you have a multi way diode saturation circuit across the outputs
for a clipper distortion unit. 6 way selection switch with 2 x OFF
positions for transformer only sound, then 4 diode selections to give
Germanium, Schottky, Silicon and LED. So a very good mix diodes with
various "trigger level" clipping drive. This version also has a diode
level control to fine tune the amount of signal hitting the diodes so
gives a blend option. Works great!! Custom designed control PCB,
Vishay Pots, 1/4" TRS gold plated made in England sockets for in/out and
a full hard bypass switch on each channel too.. Awesome bit of kit 

Super spec with the high end up to around 100k hz