Orpheus MK-3 with TVC

The Orpheus MK-3 is a DAC module designed around the well regarded Wolfson WM8740 chip. It is a differential voltage output DAC. The WM8740 is a very high performance stereo DAC designed for audio applications such as CD, DVD, home theatre systems, set top boxes and digital TV. The WM8740 supports data input word lengths from 16 to 24-bits and sampling rates up to 192 kHz. The WM8740 consists of a serial interface port, digital interpolation filter, multi-bit sigma delta modulator and stereo DAC in a small 28-pin SSOP package. The WM8740 also includes a digitally controllable mute and attenuator function on each channel. The internal digital filter has two selectable roll-off characteristics. A sharp or slow roll-off can be selected dependent on application requirements. Additionally, the internal digital filter can be by-passed and the WM8740 used with an external digital filter. Separate analog and digital power sections feature National Semiconductor low-drop out (LDO) regulators. Power supply electrolytic capacitors are Panasonic and Nichicon. All resistors are 0,1% thin film. Output stages are realized through transformers Sowter 3232 in differential mode for minimal harmonic distortion and best frequency response. The output level  is adjustable through high quality Sowter 9335 transformer volume control and 24 step gold plated attenuator  ELMA. This reduces the phase distortions and makes sound very clean. This model has balanced and unbalanced output

Battery Power supply unit

We use battery power supply with Valve Regulated Lead Acid Battery 12V/1,3Ah and automatic charge system. This allows reducing the noises from power supply. The sound is very clean with wide stage.

Technical data
  1. Frequency response: 10Hz- 30kHz
  2. SNR : 120dB (’A’ weighted, mono @ 48kHz)
  3. SNR : 117dB (’A’ weighted, stereo @ 48kHz)
  4. THD : 104dB (’A’ weighted @ 48kHz)
  5. Sampling frequency : 8 kHz – 192 kHz
  6. Input data word : 16 to 24-bit
  7. Selectable digital low pass filter
  8. Output level : 2 Vpp
  9. Output impedance : 47 kOhm
  10. Phase shift : < 2 degr
  11. Digital input : SPDIF
  12. Resolution : 24 bit / 192 kHz  ( I2S format )


  1. DAC case [mm] 160 x 72 x 220
  2. Power case:  [mm] 160 x 72 x 220
  3. Optional – luxury wooden case + engraving brass

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