Audio Note M10 Signature - Manual (Page 9)

The preamp unit of the Signature is also upgraded, I redesigned the output
transformers, this time using a much larger core of the same 55% nickel iron material
C-Cores. This allowed me to increase the bandwidth and lower the distortion of the
output transformer as compared to the original.
To further improve things I designed a new input transformer, again on a larger core.
The results are the same as for the output transformer. However here I have used a
double screen between primary and secondary to separate the grounds internal to
the preamp and external to it.
These improvements to the transformers are akin to having larger windows on your
house, more light is allowed inside so you can see more clearly.
The upgrades to the power supply and to the transformers made an incredible
difference to the absolute clarity of the machine. However, we are not in the business
of making lab instruments; The M10 is about musicality.
So, the next step was to tune the circuitry by ear, and for an audio component of this
quality level that requires time, knowledge, good ears, patience – and a good system
in which to insert the unit and listen to it.
In the end not too much was required to be done, the incredible clarity meant that I
had to slightly rebalance the voicing of the preamp (I have a box of "magic
components"!). It took some time to get it exactly right, but the results were
absolutely worth it.
Not only were we hearing into recordings to an unprecedented depth, but the sound
had a beautiful organic tone, for example wooden instruments felt like they were
wood, you could feel it inside yourself, not just hear it. Percussion was tidy, but not
blunt, rigid and "square edged": Drums had a defined dynamic envelope and
resonance.
What really left us with open mouths, and a tear in our eyes, was the representation
of voices. It seemed that before, even with the M10 Standard, you heard a voice, but
there is a thin veil between the sound of that voice and the communication with your
soul. The Signature lifted that veil, and Ella was singing to each of us personally.
We know what it means when you look at a pretty girl across the street, and then she
turns and looks in your eye..."
Andy Grove, Designer in Chief for Audio Note (UK), 2012.
AN INTRODUCTION FROM THE DESIGNER continued…