ASUS Essence One review

A Look Inside

Our audio reviews are never complete without a look inside and an explanation on what components you are investing your hard earned money in.  Certain components can look identical in size and shape but offer very different sonic qualities and overall price tag.  Without getting too technical or going beyond the scope of this review, we will explain the unique design consideration of this unit and also point out where the E1 is getting its sonic muscle that we heard during the listening tests.  It is time to operate!

Electronics Overview

S/Pdif Receiver Chip � AK4113

This is one of the AK corporation flagship digital audio receiver chips and the unit handles all S/Pdif communication for the Essence One.  This product offers input support for 8Khz, 11.025 Khz,16Khz,22.05Khz,24kHz, 32kHz, 44.1, 48Khz, 64kHz, 88.2, 176.4kHz, 192khz.  AKM4113VF Specification Sheet

Chipset � CM 6631

C-Media CM6631 is the first true high-speed USB2.0 APU which has audio processing capability up to 192 KHz/32bit.  This product offers asynchronous USB input for the Essence One and this input method is usually sought after by audio lovers as it is basically immune to timing issues such as jitter that plague other design types.  Based on some research, it would seem a few companies are using this chip in new USB audio designs.  Given this chip is the worlds first true high speed USB 2.0 devices and offers asynchronous signal timing, we can understand why.

Chipset � Analog Devices ADSP-21261

This chipset is the main audio processor for the Essence One unit.  The 21261 is a 900MFLOP, 150 MHz SHARC audio processor.  This chipset handles the upsampling features of this device.

DAC � PCM1795

The High end PCM 179X series of DAC chips has been seen in other PC audio products and in more consumer based audio products then we can mention here.

This DAC offers sampling rates up to 32/192 KHz, a high Dynamic Range of 123 dB and an impressively low THD+N of approximately 0.0005%.  This unit also boasts an 8X Oversampling Digital Filter.

In the Essence One, this DAC chip is used in a different way then previously seen in other PC audio offerings, we will speak more about this in the electronics overview section. 

PCM1795 DAC Spec Sheet