Announcing all new USB Headphone Dongle  - Clarity Pettie

We are glad to announce that our first official high-fidelity headphone amplifier Clarity Pettie is ready for some preview. 

The Clarity Pettie is really our first marketable headphone amplifier, unlike the technical demo unit. 

Specification:

  • Sensor-less motional feedback headphone driver
  • Up to 384KHz in PCM mode
  • Up to DSD256 in native mode, and DSD128 in DoP mode
  • DSD128 by DSD over PCM (DoP) on Mac OS
  • DSD256 in native DSD mode on Windows
  • Frequency response 5-15kHz in PCM 44.1kHz and 48kHz,
  • Frequency response 5-40kHz in DSD, PCM >88.2kHz conditions
  • Hardware volume control support on USB interface
  • Customized up-sampling filter for time domain optimized performance
  • Analog and Digital combo volume control 
  • Driver free operation on Windows 10, Windows 11, Mac OS, Linux, iOS, Android
  • Verified computability with Audirvana Player
  • Typical Power consumption 0.5W via USB-C
  • Firmware upgrade via USB in DFU mode

FAQ:

  1. What is sensor-less motional feedback?
    We use back EMF cancellation scheme to closed-loop control the motion of the headphone diaphragm. Since the driver control the actual movement of the diaphragm, instead of the driving voltage, it reduces THD, IMD and produce accurate bass. However, the driver is match too a specific headphone when operating in this mode. Replacing the headphone without re-tune the amplifier will lose the benefit of the sensor-less motional feedback, or worse headphone damage. It also produce erratic measurement result if the amplifier is driving a measurement equipment. (an Audio Precision analyzer is not a headphone, there is no moving diaphragm on it, thus no motional-feedback.)
  2. What is time domain optimized up-sampling filter?
    We optimize the up-sampling filter in the DAC so that we produce minimum ringing and maintain group delay at best effort. This improves the spatial reproduction of the sound stage. Of course nothing comes for free. This is at the expense of elevated noise out of the audible band. So we prioritize sounding on the human side than the noise on the instrument measurement side. 
    Also note that, in DSD mode there is no signal processing, so the up-sampling filter is bypassed and become irrelevant. 
  3. Why is Mac OS limited to DSD128?
    Mac OS does not have mechanism to support native DSD playback. There is no industrial recognized standard on how to transport native DSD stream under USB Audio Class specification. Thus, DSD stream is packeted as a fake PCM stream and sent to the DAC. This has bandwidth limitation and capped at DSD128 when operating under DSD over PCM (DoP) mode on Mac OS, iPhone, Android and Windows.