6
DESIGN PHILOSOPHY
I. Design Philosophy and Approach (continued)
To maintain “Precision Bias” requires an advanced bias circuit that must have a very high
degree of stability under a wide range of temperatures and load conditions. Most amplifier
bias networks are of such high impedance and poor thermal regulation that at the extremes
of operation, bias currents are ineffectively controlled. Advanced tracking techniques used in
the 60.0 result in absolute control of bias currents under all conditions.
The main power supply of the amplifier consists of a 3000VA transformer with independent
rectifiers to isolate the channels from one another. 184,000 uF of total capacitance provide
effective filtering of all AC ripple.
These attributes result in an amplifier of such extreme linearity and bandwidth that no overall
feedback correction is required or used. One advantage of this is a high degree of immunity
from interactions with loads or cables and a superior transient response. An extremely low
nonreactive output impedance is maintained well beyond 20,000Hz. the resulting uniform
damping factor is not commonly found in other designs.
The chassis of the 60.0 is constructed of machined aluminum milled to very close tolerances
yielding the seamless appearance characteristic of previous products from Coda. As with all
high-power amplifiers, heat dissipation is important. The 60.0 uses six massive aluminum
heat sinks without fans for efficient, noiseless and clean thermal relief. The thermal coefficient
of the 60.0 heat sinks is one of the lowest and most effective in the audio industry.