The Thermionic Culture Snow Petrel is designed as a two channel microphone amplifier for all types of microphones, especially certain ribbons, eg. Coles 4038, which have a lower output level than others but offer superb quality. Their full potential can be realised with this high gain unit as it has a natural valve sound with very low background noise and distortion. The passive "AIR" control is provided to lift the very high frequencies as many ribbons suffer a little loss there and this compensates for that perfectly.
It will give excellent results with any microphone and they have included +48V phantom power and -20dB pad for use with FET and self-amplifying microphones.
There are 3 valves in each channel of the Snow Petrel, the first 2 acting as the main amplifier preceded by a specially designed Sowter input transformer, then after the passive HPF and Air controls comes the Tung Sol (6189) output valve and Sowter 1:1 transformer. This combination is capable of a clean output in excess of +25dBu. Of course many users may want valve and transformer colouration to give a bit more "edge" to the sound so Thermionic have provided 2 attenuators. O/P trim comes after the 1st 2 valves and can be used to provide a little 2nd harmonic colouration, then the "ATTEN" is at the actual output so if the unit is driven hard it will add transformer as well as valve distortion.
Designed originally for use with the Coles 4038 as a super-clean low noise unit, after extensive field tests in UK, Norway and France, They've found it sounds exceptional with ANY microphone including the classic Neumann U 87, perhaps because:They use extra-low noise valves with NO solid state impurities in the audio path, plus VERY special Sowter in and out transformersInput impedance is higher than usual to preserve clarity and can be tailored to individual mics with the Hi/Lo and Pad switchesIncredibly musical and progressive saturation for distortion lovers when overdriven and by employing the fine and coarse attenuatorsControls include Gain, from 40 to 75 dB, switched, HPF to reduce "proximity effect" and "Air" to add that extra clarity.Carefully hand made and tested in Harlow, England