Electronics Overview
We like to add this section to outline and give a brief overview of exactly what hardware the end-user receives if they invest their hard earned dollars in this soundcard. So, lets have a look under the hood of this bad boy and see what we have.
CM8888HT APU Chipset
The main feature and difference between this new offering from C-Media and the legendary CM8788 chipset is the interface. This new chipset is native PCI-E whereas the 8788 offered a PCI interface and Xonar products that offered PCI-E connectivity required a separate bridging chip.
We will look at the headphone output and speaker output sections separately.
Headphone Output Section
The headphone output circuitry on this card is quite similar to what ASUS has utilized on the Essence series soundcards. Starting from the right hand side, we have:
PCM 1796 Digital to Analog Converter (DAC)
This DAC chip offers a dynamic range of 123dB and a THD+N rating of 0.0005%. This DAC chip is a Current (I) output part so it requires a differential current to Voltage converter section.
JRC2114 (Opamps)
The pair of JRC2114 opamps is used as a differential input current (I) to voltage (V) converter section. These opamps are a more generic opamp but they have been seen in many audio products including the high end Essence series and the HDAV 1.3 soundcards. The chip has a slew rate of 15V/µs typ. And a low noise 0.9µVrms
TA6120A2 (Head Amp)
ASUS is fond of this head amp chip as it has been seen in other designs. The chip allows gain range setting through the driver to allow the user to connect headphones with different impedances.
