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

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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 the homes of regular music lovers.

The input and driver stages of all EWA amplifiers operate in high speed SECA, pure class A. Smaller amplifiers in the range output Class A P/P (Push/Pull), and class A/B. The larger amplifiers also incorporate constant current drivers, and their output is class A Push/Pull. Very little negative feedback is used in the design.

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 SECA.

Featuring very low NFB (Negative Feed Back) EWA amplifiers are conservatively rated for gain and power; notionally they will give 22V gain for 1V input. They will actually do rather better than this, making every EWA amplifier sound larger than it is. 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.

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.