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Special Design Features

Rugged Build

 

Mechanical strength has been a hallmark of Perreaux products since the

 

Quality

 

company first started production back in 1974. The concept behind the physical

 

 

design and construction is that each structural member should contribute to both

 

 

rigidity and performance.

 

Stiff Power

 

The E160 incorporates a custom designed, toroidal power transformer,

Supply

 

employing heavy gauge wire that reduces copper losses to a minimum. An

 

 

electrostatic shield prevents AC line borne interference from entering the signal

 

 

path. The power supply filter capacitors, totaling 20,000μF have exceptionally

 

 

low inductance and internal resistance. They charge and discharge in response

 

 

to load demand far more rapidly than conventional storage capacitors and are

 

 

capable of delivering the instantaneous current required by the output stages,

 

 

providing optimum dynamic range and transient response. The wiring from the

 

 

power supplies to the output boards is designed for unimpeded transmission of

 

 

the required current and voltage and utilizes heavy gauge, copper wire cables.

 

 

Since power supply leads radiate at signal frequencies, all wiring is carefully

 

 

loomed to minimise this effect.

 

Hybrid Class

 

The bi-polar transistors used in the E160 are run in Class A mode. This avoids

A/AB

 

the crossover notch distortion and the resulting odd-order harmonics present, to

 

 

some degree, in all other classes of operation. The devices used in the E160

 

 

output stage are MOSFETs, which with high quiescent current circuitry, are run

 

 

in the equivalent of Class A to 10 watts. Beyond this point the output class is

 

 

technically Class AB (hence the hybrid nomenclature), but with a major

 

 

difference. The combination of MOSFET characteristics and their application in

 

 

this circuitry, result in crossover distortion so minimal that it is virtually non-

 

 

existent.

 

MOSFET

 

The E160 output stage takes full advantage of the unique qualities of MOSFET

Output Stage

 

devices and in many ways they are superior to bi-polar transistors. A major

 

 

advantage is their tendency to draw less current over a large section of the power

 

 

bandwidth as their temperature rises (Negative Temperature Coefficient), hence

 

 

self stabilising thermally, whereas bi-polar transistors draw more current as their

 

 

temperature rises (Positive Temperature Coefficient) and protection circuits

 

 

become mandatory to prevent thermal runaway and eventual self destruction.

 

 

MOSFETs have the ability to swing fully across the amplifier’s internal DC

 

 

voltage and are therefore true "rail-to-rail" devices.

Using MOSFETs

 

 

encourages the highest performance from the balance of the internal amplifier

 

 

circuitry.

 

Earthing

 

Perreaux engineers pay particular attention to designing the product to ensure

 

 

maximum separation between internal signal and power earths, only meeting at a

 

 

central starred point.

 

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