Closer Look: TerraTec Aureon 7.1 Space PCB Design
The PCB of Aureon 7.1 Space is made of dark glass-cloth laminate. Its dimensions are nearly identical to DMX 6fire and 1.5cm shorter than Audigy. The gold-plated back bracket carries six mini-jack and two optical connectors. There are also two 10-pin connectors on the board that might seem to be intended for extension modules. But the manufacturer doesn’t offer any daughter-cards for Aureon and these connectors serve purely technological purposes. In fact, the official documentation is scarce in describing technical nuances (for example, it doesn’t even tell that Aureon is based on Envy24HT! Quite a shame!), so we decided to explore the hardware part of Aureon more closely.
The heart of Aureon 7.1 Space is a multi-channel audio-controller aka VIA Envy24HT (formerly known as ICE1724) supporting twelve input and twelve output channels (ten of them are analog and two more are digital). The chip has a powerful integrated digital mixer of a high resolution (considering the processing of 20 channels).
Besides purely musical capabilities (MIDI and GPIO support), the controller supports a joystick game port, which seems to be a legacy feature (manufacturers prefer USB for their new game manipulators). Moreover, VT1724 is responsible for communication with the PCI bus.
The controller flowchart available on VIA’s website is too simplified and doesn’t tell of any new units integrated into the Envy24HT architecture. Moreover, this flowchart resembles very much the flowchart of ICE 1712 controller IC Ensemble has been producing since 1999 (when no one ever heard of “audio solutions from VIA” :)). By the way, you can find more detailed info on Envy24HT at VIA Technologies' website.
Envy24 ICE 1712 Detailed Block Diagram
The effect-processor functions are entrusted to the digital 96kHz audio-interface receiver from Cirrus Logic: CS8415A-CS. This chip receives and decodes one of the seven audio channels according to appropriate interface standards (SPDIF, AES3 and so on).
Cirrus Logic: CS8415A-CS Block Diagram
The flowchart shows that there is a multiplexer at the input of the device. It collects data from seven audio channels one by one. Thus, the receiver processes data from one of the channels chosen by the multiplexer during one clock cycle; then they are sent over for further processing. Extra audio effects can be added to the sound data at this processing stage. CS8415A is used not only in audio cards, but also in AVR, CD-R, DAT, DVD and MD devices.