ESS ES9219C DACThe experts at Qudelix wanted the device to work as a universal DAC/AMP for both high-sensitivity IEMs as well as high-impedance open-back headphones. Qudelix wanted it simple, small, yet but powerful. In addition to the sound quality and the maximum output power, they also needed to consider the battery time as well, concerning the nature of the device.
Qudelix’s engineers tried many DACs and Amplifier ICs and found ESS9219C is the best option for their goal. Besides the sound quality, the primary advantage of ESS9219C is that the built-in amplifier delivers the maximum output voltage up to 2V RMS. Furthermore, it supports the 1V RMS option at the same sound quality to save power consumption.
For high-sensitivity IEMs, the amplifier noise figure is the most important. The high-sensitivity IEM is so sensitive that it translates every electrical noise or thermal drift into audible acoustic sound, usually white noise.
On the other hand, the high-impedance headphones require a higher power amplifier. Those headphones usually have low sensitivity, and they are free from the white noise affected by the amplifier noise characteristics. Instead, they need higher power from the amplifier output to deliver enough loudness and headroom.