How to build Symmetrical Class A Preamplifier

August 7, 2010 - category: Audio preamplifier


A very simple but very good amplifier unit, with low distortion. A similar modification was used as a preamplifier HAFLER. The quality however of the reproduced sound in all the symmetrical amplifiers regardless of the cost of the necessary materials, transistors, capacitor and resistors.

Circuit diagram

Circuit diagram

Part List

  • R1= 100Kohm
  • R2-3= 82Kohm
  • R4-5= 22Kohm
  • R6-7= 100ohm
  • R8= 5.6Kohm
  • R9= 100Kohm
  • R10= 1Kohm
  • C1-3= 10uF MKT
  • C2= 56pF ceramic
  • C4-5= 100nF 63V
  • C6-7= 47uF 40V
  • T1-2= BC 550C
  • T3-4= BC 560C
  • T5= BC 516
  • T6= BC 517

circuit from http://users.otenet.gr/~athsam/symmetrical_class_a_1.htm

If you liked this page please consider sharing. Thanks!

Bookmark and Share

Previous and next post from Audio preamplifier