Preamp PD2

PD2

Preface:

With the PD2 we wanted to make an reference pre-amplifier. Designing an pre-amplifier is not an easy task, not even with opamp’s. When designing this pre-amplifier we decided to make it module build, by making discrete amplifier modules, separate DAC section and separate phono amplifier section as well. This way it will always be possible to get upgrades for the pre-amplifier as we wanted to make this pre-amplifier an lifelong investment.

All our discrete amplifier modules are single gain stage designs. We use exclusively folded cascode voltage feedback or Current feedback designs depending on the circuit they are used in.

All parts of the circuits has been extensively tested before getting part of the design of the PD2 preamplifier.

By using our own discrete design with a fine tuned blend of JFET’s and bipolar transistor we have taken control of the IP. The used gain stages are module based. So a lifelong upgrade path of the PD2 can be made.

IMG_1682

The Volume control is based on highest quality DAC8812 which enables 0.5dB from -120 to +12dB while ensuring low noise floor low thd.

IMG_2083

 

The DAC section features ultra low noise crystals from Crystek, but also galvanic isolation of the USB port and reclocking of DAC data enabling deep dark background while keeping focus on the soundstage.

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We believe that a carefully designed printed circuit board and state of art circuit will give an extraordinary level of sound reproduction. Internally as well as from the outside we want this amp to be jewel.

Operation of the amplifier:

To make the amplifier as versatile as possible we have chosen to incorporate and high resolution 4.3″ tft touch display. Or menus are logical and does not reflect all the colors of the rainbow. We want the display to be timeless, discrete and informative at the same time.

Specification:

  • 3 single ended inputs that we convert to balanced right at the input.
  • 2 balanced inputs
  • Fully discrete from input to output.. No opamps
  • Bandwidth: > 500KHz
  • 1 balanced DAC with 4 x SPDIF inputs and USB AUC 2. PCM 384KHz/32bit and DSD 256
  • USB is galvanic isolated
  • Reclocking of DAC data
  • Ultra lownoise crystals in the DAC section.
  • 1 MM/MC RIAA section Optional
  • Fully balanced volume control -120 to +12dB
  • 1 single ended output
  • 1 balanced output
  • Remote : Apple TV remote or Phison Audio remote
  • WxDxH : 440x312x100mm
  • IEC inlet: 100-120VAC or 200 – 240VAC

Manual:

PD2 Owners Manual