The box in which the FireWire card is housed is built around the front and rear surfaces between which a sturdy metal element is housed that constitutes the body of the equipment. All the electronics are on a single printed circuit and there is only one auxiliary circuit behind the front of the casing, mainly for the indicators and lights.

Operation is based on two main circuits, a Wolfson WM8770 codec and a BridgeCo DM1000 processor. The WM8770 offers eight channels of digital/analog converters that can operate from 8 kHz through 192 kHz at 24 bits. On the other hand, it only incorporates a single analog/digital converter (two-channel, for the stereo) that can operate from 8 through 96 kHz at 24 bits. The converter is preceded by a selector offering eight stereo channels with analog gain adjustment but it is still the only one and does not allow mixing. It is here that this limitation of the FireWire card can be explained. The DM1000 is a complex, specialist audio and video circuit incorporating a FireWire controller. It consists of a RISC 32-bit ARM496 processor with DSP extensions operating at 100 MHz.

Test Configuration And Audio Measurements

External cards have the undeniable advantage of being remote from that focus of electromagnetic pollution, the computer. They are thus capable of attaining very high levels of performance. High-performance internal cards often use an external module to solve the problem. However, the mass-market external sound cards that were on the market until now were generally low-priced products that compromised on performance. The Aureon FireWire clearly has higher ambitions and can claim higher aspirations for a mass market card, whatever the category. It may be considered too bulky by some people who like computing on the move and the price is nothing to sneeze at, both factors of which could act as deterrents.

In line entry, for an adjusted gain of 0 dB (all the other settings at maximum being 0 dB), the maximum level prior to saturation is 2.6 V, which ensures compatibility with all the standard mass sources. Under these conditions, the output offers a maximum level in the order of 2 V. Gain is adjustable (by using the cursor on the right of the source selection) from -12 through +19 dB (in nominal values). Using minimum gain, you can go up to 4.6 V in input, and with maximum gain saturation reaches 295 mV. This means it can be adapted to any source, which is a strong plus for FireWire.

The output level at digital 0 dB is in the order of 2 V (1.95 V), which is perfectly suitable for the sort of uses to which it might be put.