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

All text and images copyright 2019 ABCaudio & Elsdon and Wonfor Audio

  • EWA M-50-P Pre Amplifier


    Single Ended Class A pre amplifier 


    All EWA products bought from ABCaudio webshop can be returned within thirty days for a full refund (minus shipping), amounting to an almost risk free trial period.


    • Specification

      Built as standard for UK voltage, can be built to operate elsewhere. Please specify when ordering. 


      Inputs:  All inputs are specified for a line‐level output of 1 volt into a 10kΩ load.


      Moving Coil: Standard loading 100Ω ‐ 470Ω with a loading capacitance 1000pF. Input sensitivity is typically 100µV. Frequency 20Hz – 20kHz ± 0.1dB.


      Moving Magnet: 
      Standard loading 47kΩ with a loading capacitance 100pF. 
      Input sensitivity is typically 5mV – 10mV. 
      Frequency 20Hz – 20kHz ± 0.1dB. 

      Aux input 1: 
      Standard input for a line levels device. 
      Input senstivity 200mV typical. 
      Frequency 0.5Hz – 200kHz ± 0.1dB. 

      Aux input 2: 
      This input has a subsonic and DC roll‐off making it ideal for portable devices which often have small DC on their outputs. 
      Input senstivity 200mV typical. 
      Frequency 1.5Hz – 200kHz ± 0.1dB  

      Outputs 1 & 2: The frequency response is specified for 1 volt output, both channels driven. 



      • Minimum load 100Ω 16Hz – 200kHz. 
      • Nominal load 10KΩ 0.5Hz – 200kHz. 
      • High level load 100KΩ 0.5Hz – 200kHz. 




      • Frequency Response 10Hz – 50kHz into 65Ω load. 
      • Maximum output voltage with no load is 15V Peak. 
      • 1 volt input level gives a peak output of 4V. 


      Power Requirements: 
      Standby Power Less than 1W.