Thermionic Culture The Robin

The ROBIN is a very simple box, but rather special in terms of
quality and application, and has the following features:
– NO solid-state transistors or ICs so NO 48V power required;
– PHANTOM POWER to The Robin must be OFF;
– HIGH spec transformer (E.A. Sowter) to match impedances;
– BYPASS switch so that the transformer is out of circuit and
you connect directly to the mic amp input. This works well
with the Snow Petrel as it has a relatively high impedance
– THE AMP JACK is connected directly to the DI JACK for a
separate amplifier to be used;
– EARTH LIFT disconnects the ground connection (Pin 1 of
the XLR output) from the circuit in the box to prevent a hum
loop which may occur if an external amplifier is used or the
instrument is powered from a grounded mains supply;
– SWITCH GUARDS are provided to protect the switches from
possible damage and the box is of very rugged construction.

SPECIFICATION with the transformer in circuit is pretty basic but the
following facts are worth noting in relation to the transformer:

– It has a 10:1 ratio and input impedance is 100x the input impedance
of the mic amp, so a mic amp with 1kΩ input impedance means that
the transformer will present a 100kΩ load to the instrument.

– The frequency response is flat over the audio range and there is no
measurable distortion added by The Robin.

PRIS: Ring