QRV-08 The high performance smd headphone amplifier with quadruple super regulators

Click on the picture to see a larger view of the pcb.

The performance is outrageous in headphone amp terms. See the technical data!

Interesting features:

  1. High speed, low distortion current feedback design.
  2. All discrete design of the amp itself.
  3. Offset trim with a trimpot and/or with a DC servo.
  4. Input LP-filter if you have problems with RF interference (you should have a filter though).
  5. Room for DC removal cap (if you need this)
  6. High speed and high performance SMD buffer as output stage.
  7. High current transistors as output stage.
  8. Extremely high quality dual mono power supply with large smoothing caps and transformers on the pcb and with four extremely high speed and high performing super regulators.
  9. Fits any headphone (except for electrostatic of course).
  10. Any bad feature? Possibly that this project requires skills more than usual in order to succeed. The skills are about soldering the parts in the right place. If you'll manage that, this isn't so hard after all. Building time 4-6 hours only.

My design goal was to make an ultra high performing amp with only "normal" parts but well balanced amp in terms of component choices and a well-tested topology. I think I have succeeded because this design is one of the best I ever have done so far and I'm pretty sure that the power supply is one of the most advanced regardless of price in commercial products.