Description of the MC TR01 moving coil transformer.
Posted on by Ben Lamb -
This completely passive moving coil transformer system requires no power to operate, it is incapable of introducing any more electrical noise into your system. Very high quality, specialised audio transformers are used which are produced in the UK. The transformers have an internal screen between the primary and secondary windings and are individually shielded inside Mu Metal cans to significantly increase immunity from magnetic fields.
The transformers enclosure is made of extruded aluminium alloy and provides a hermetic shield against R.F. interference. High quality gold plated RCA/Phono connectors are used and an arm earthing point is provided. The left hand switch controls whether the chassis is grounded or not. The right hand switch provides an earth path for arms which are grounded through the left hand RCA/Phono ground like the popular Rega arms. Switch position up is off and down is on. These extra features expand compatibility to a greater range of arm systems.
The transformer produces a mean gain of 17.5db taken from measurements at 20hz, 9khz, 16khz and 20khz. Input impedance is 600ohms and output is 27kohms. Frequency response is 15hz to 25khz and I provide some test images to show that these figures are genuine and not plucked from the air. In the images the red trace shows the amplitude of the sine wave output from the transformer and the yellow trace is the input to the transformer from a signal generator. Harmonic distortion is incredibly low with a MC transformer system and the sound is very different to a dedicated MC amplifier being much more natural and pure. Coupled to a good phonostage the noise floor is kept as low as possible. Using a typical MM phonostage with 40db of gain you will have a total of 57db gain with this transformer, enough to run cartridges down to 0.3mV of output voltage.