Model A Mono Compressor
The mono compressor has a circuit loosely based on a Fairchild 660. Its design came out of my love
for variable mu tube compression. Maintaining and repairing the three Fairchild’s at Capitol
gave me a pretty deep understanding of the circuit and what was essential to its signature sound.
I also repaired and listened to other typologies such as the Gates Sta-Level and UA 175.
There was just something tighter and thicker about the Fairchild’s sound and compression
characteristics. One unique design aspect is that the amplifier stage also doubles as the gain
reduction element. This way there doesn’t need to be DC blocking capacitors in the signal path.
The Magic Death Eye’s signal path is a passive input attenuator, input transformer,
class A tube amp stage and output transformer. All DC coupled. The AC phase shift is minimized
and there is lower noise compared to multistage designs. With the signal path being so simple
with very few components, each components is crucial to the sound.
Which brings me to TRANSFORMERS. In addition to build quality and research, transformers
are what makes the Magic Death Eye unique among other offerings.
I was never quite satisfied with off the shelf offerings like Jensen, Cinemag, Sowter,
or Lundahl audio transformers. These are all great transformers
and spec out very well. Some have bandwidth up to 100 kHz. But why do all the engineers like
the vintage stuff so much? Their “magic” micpre or compressor was never a modern boutique
unit but some dirty old vintage unit that weighed 50 lbs or more. The common thread
seemed to be UTC or Triad transformers. Even in old solid state units, there was that old
transfromer in there matching impedances. The audio gateway the the rest of the circuit.
The bringer of luscious harmonics and “color”.
The newer transformers seem almost too good, after all they strive
to be transparent and have the lowest distortion possible.
They also had to figure out how to wind them in a less laborious way using computer aided
winding machines that eliminated the need for tape or “fish paper” between each layer of wire.
I set forth to learn how to wind my own transformers using the old tape layer winding technique
used in UTC and Triads. Using oversize cores and having happy accidents along the way,
I finally came up with my own unique designs. They take way to long to make but its so worth it.
There hasn’t been one engineer producer or artist that wasn’t just blown away
with the sound of a Magic Death Eye.