SECA technology - an overview.


Single Ended Class A


EWA amplifiers will provide you with the ultimate experience in musicality and loudspeaker control.

State of the art class A performance is guaranteed by Colin Wonfor’s peerless experience in power supplies and audio engineering. 

Colin designed and built the largest ever Single Ended Class A audio amplifiers, which are pure class A all the way through from the input to the output terminals. The current generation of SECA derived circuits, available in EWA amplifiers, is rather different; representing a refinement built on this unique heritage which brings extraordinary class A amplification into our homes in a much more efficient manner.

The input and driver stages of all EWA amplifiers operate in high speed SECA, pure class A. Smaller amplifiers in the range then output class A/B. The larger amplifiers also incorporate constant current drivers, their output is class A Push/Pull. 

This can be described as a quasi hybrid approach, as the grip, power and efficiency of an A class P/P amplifier is in full evidence, but the character of the sound is very much pure SECA.

Featuring very low NFB (Negative Feed Back) EWA amplifiers are conservatively rated for power - they will actually do rather better than stated, making every EWA amplifier equal to the task in hand. Each amplifier has very wide bandwidth, very fast rise time and uncommonly high damping factor, meaning EWA amplifiers are in complete control over your loudspeaker. There is 22V gain for 1V input.

EWA pre-amplifiers are Single Ended, and electrically very quiet. They are superbly fast and detailed, digging deep into every musical nuance. They are also equipped with excellent, high performance headphone amplifiers as standard. 

Contact us:  United Kingdom. EWA designs for cables and amplifiers, by Colin Wonfor.

All text and images copyright 2020. ABCaudio and Elsdon & Wonfor Audio.