Interview - APU and SoundStorm for EPoX nForce2
Date: 12.11.02

This Question and Answer is to help users to identify what the difference are between the Nvidia Soundstorm and the Nvidia APU and provide the users the understanding while this should help users pick which system is right for them.

What is Nvidia APU?

In a nut shell, the Audio Processor Unit is a hardware audio accelerator that provides both audio output and input streams. This Unit allows the streams to be transferred to any CODEC or USB audio system. The APU has four main sections:

1. Setup Engine

2. Voice Processor

3. Global Processor

4. Dolby Interactive Content Encoder

The most important part on this Q and A is the Dolby interactive Content Encoder which I will be emphasized mainly on. The Setup Engine is mainly the unit to regulate and manage memory allocation. The Voice Processor obtains the digital signal processing (DSP) which is responsible for processing voices and mixing in buffers. The Global Processor is a unit adds varies effects to the data in the mixer buffers and package the final output stream. The Dolby Interactive Content Encoder is also built around the DSP and is responsible for encoding the Dolby Digital (AC-3) data that could be sent to the S/PDIF (Sony/Philips Digital Interface) to external consumer decoder (i.e. stereo receiver). This function gives the quality of Dolby Digital 5.1 over 6 speakers which includes left front, right front, center, right rear, left rear, and sub-woofer.

So What is Soundstorm anyway?

SoundStorm has all the functionalities of the APU as stated above. SoundStorm has all the hardware output sockets implemented on the motherboard or a daughter card.

The SoundStorm hardware minimum requirements are as follows:

Must haves:

-Discrete (non-shared) front left and right analog outputs
-Discrete (non-shared) rear left and right analog outputs
-Discrete (non-shared) center and subwoofer analog outputs
-Discrete (non-shared) SPDIF digital output (Coax recommended, but they can do Optical)
-Discrete (non-shared) line in analog inputs
-Discrete (non-shared) microphone analog input
-MCP-T with Dolby Digital enabled

What are the differences between the Nvidia APU and the Soundstorm?

SoundStorm gives the quality of Dolby Digital 5.1 over 6 speakers on the motherboard or the daughter card level instead of having separate output hardware to translate the digital sound to the speakers



What does the Current EPoX nForce2 boards have?

The current nForce2 boards are APU ready. The boards have everything except a center/ subwoofer analog output. The current nForce2 boards while set as default has only mic, audio out, audio out. These boards do have the capabilities to change the default setting to produce 6 channel of audio but they will not be discrete. But the sound quality should not have any significant difference. Current EPoX nForce2 boards do have S/PDIF. If one should want to have the audio features of SoundStorm, one can hook the S/PDIF coaxial or optical cable to a sound system by purchasing an add-in card (EP-SPD650). But without the S/PDIF, you already have the (AC-3) which means the motherboards already obtain the capability of Dolby Digital 5.1.

I hope this clarifies the mystery of SoundStorm. If you do have any other questions, please feel free to contact me by email: Samuel.kang@epox.com or edward@techwarelabs.com