GTT Perspective · Master Fidelity
A volume control designed at the silicon level.
The NADAC L is Master Fidelity's line stage preamplifier. Its volume control is a custom analog attenuator chip, stepped in 1 dB increments from 0 dB to −60 dB.
The line stage in the NADAC system
The NADAC L completes the NADAC front end: server, master clock, converter, and line stage. Master Fidelity designed its volume control as a dedicated chip, developed with a semiconductor partner. It is the same decision that produced the proprietary converter chip in the NADAC D: design the part rather than buy a general-purpose one.
Left and right channels are isolated from the power supply through the signal path. The analog circuitry and the digital control system are galvanically isolated from each other. Balanced connections are true differential; single-ended connections are true single-ended.
What the engineering actually does
Volume, in 1 dB steps
0 dB to −60 dB in 1 dB steps, with channel imbalance under 0.1 dB and no click noise.
A chip of its own
The attenuator is a JFET-like custom CMOS ASIC, developed with a semiconductor partner. Master Fidelity describes it as continuing the approach of the NADAC D's proprietary DAC chip.
True dual mono
Left and right channels are completely isolated, from the power supply to the signal processing.
Analog kept apart from control
The analog audio circuitry and the digital control system are fully galvanically isolated.
Inputs and outputs
Four balanced XLR and two single-ended RCA inputs, one selected at a time. Three balanced XLR outputs and one single-ended RCA output.
Peak meters
The front-panel meters are true analog-style peak meters, accurate to ±0.05 dB.
Resistors
Following the NADAC C, only ultra-precision 2 ppm resistors are used throughout the audio signal path.
Questions we hear in the listening room
What is the NADAC L?
Master Fidelity's line stage preamplifier, and the line-level control in the NADAC front end alongside the NADAC S server, NADAC C master clock and NADAC D converter.
How is the volume controlled?
By a custom analog attenuator chip, in 1 dB steps from 0 dB to −60 dB, with channel imbalance under 0.1 dB.
What does it connect to?
Four balanced and two single-ended inputs, one selected at a time; three balanced outputs and one single-ended output.
Where can I hear Master Fidelity in the US?
At GTT, North American distributor for Master Fidelity — by Private Audition in our Private Listening Room in Long Valley, New Jersey.
Further reading
Private Audition
Hear the NADAC front end for yourself
GTT is the North American distributor for Master Fidelity. The NADAC components are auditioned as a complete front end in our Private Listening Room in Long Valley, New Jersey.