ZESTO AUDIO: EROS 300 Class A Monaural Power Amp

EROS 300

They write:

Design Philosophy:

Design Challenge

The challenge designing the Eros 300 was the conflict created when you want a lot of power, low noise and most importantly you want it to be musical. It took over 3 years to develop the Eros and 79 circuit designs later. I always look at the design from two points of view, as an audio engineer and an electrical perspective. Each design phase is based on a 50/50 balance between the technical spec and listening to each component change.  Ultimately, the final design must sound good because who listens to sign waves anyway.

Class A amplifier design

Class A has less cross-over distortion and therefore is more musical. The tubes are always on, so you have power when you need it. Class A is fast and responsive. There is no lag, providing your music more punch, transient response, better dynamic range and transparency.

Secret Sauce

The secret to a good power amplifier design is matching the circuits of the power supply to the amplifier. The Eros 300 is a choke based power supply with a custom toroid power transformer that gives you maximum power with no compression. It’s the most musical design because it retains all the dynamics from your sound source.

Lots of choices

How many tubes is enough? How much power is enough? I decided that 6 KT88’s and 150 Watts of Class A power was a good balance. More tubes and more power didn’t actually sound better, in fact, worse. Adding more tubes would have created more heat and less reliability.

What is EROS?

In Greek mythology, EROS is the God of Love and Desire.


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