I just opened my Terratec Aureon FireWire 7.1 few days ago. I will explain for modding possibility with the picture below.
First of all, Terratec Aureon FireWire 7.1 is very interesting. It is an external sound card based on FireWire interface. Uniquely, it may act as a stand alone 2-channel D/A without the needs of PC. Just plug the supplied adaptor, plug the input Optical, the plug your amplifier to its analog RCA line-out. The D/A is Wolfson WM8770IFT 24/192 capable.
The first mod that we should do is off course to build a better adaptor/power supply. The supplied on is very crappy (just like the one to charge your phone/PDA, switching design I believe). I won’t use this for my audio (especially my D/A which may be very sensitive with power supply noise/problem). I will not discuss a lot about the power supply design. I will discuss it later (on other post).
Inside of the card is very simple (picture below). The D/A WM8770IFT (blue circle) provides 4 analog output to the coupling capacitor (yellow line). Finally, the sinyal fed to the op-amp. Four (dual) op-amp used in the 8 channel analog out.
Parts to be Replaced
The improvement could be made by replacing the D/A power supply capacitor (yellow box, picture below). Better capacitor ini this section will result a better sonic quality (better supply for your D/A). Elna Cerafine or Black Gate is a mandatory for this section.
The red box is the coupling caps. My recommendation is Black Gate NX Hi-Q series. Very excellent for this purpose, though the price is quite high. I think I will change the capacitor for 2 front channel only because my main use from this card is for 2 channel D/A. I will not waste my money to buy another 6 BG NX Hi-Q to replace the rear, back, and center/subwoofer channel 😉
The op-amp (blue box) is JRC 4580. Not an impressive stuff there. I will see the chance to bypass the op-amp so I will feed the signal directly from the D/A to my external pre-amp (with extra coupling caps off course). Or if that’s impossible, I will set up a simple one stage tube pre-amp.