The DAC & ADC

The DAC

The DAC is the heart of audio quality when it comes to sound cards. The Auzen X-Fi Prelude 7.1 shines in this area with its Asahi Kasei derived AKM-4396VF. This is a 120dB dynamic range-capable DAC with -100dB of total harmonic distortion (THD) and noise. These are all great numbers.

The high level of oversampling on this chip @ 128x is particularly welcome. If I remember correctly, aliasing filters work better at removing noise as the oversampling rate increases.

So far, I haven't heard other AKM DACs, but I will be comparing it to my experience with the BurrBrown PCM1794, the CS4398 and the AD1852 later in this review. All in all, its specifications are most impressive. In fact, before the 32-bit AKM-4397 arrived, this DAC was very much the top-of-the-line. This should give you about the level of audio quality of the Creative Sound Blaster X-Fi Elite Pro sound card.

Digital Input & Output

Digital Input & Output

Being a Sound Blaster Audigy 2 user, I don't understand why Creative refuse to use standard RCA jacks for digital output. Instead, they forced me to get some exotic Mini-to-RCA converter to get it to work with my external DAC.

At least Auzentech had the common sense to stick with standard RCA jacks, allowing for greater flexibility when it comes to cabling. So, I have absolutely no complaints here.

I also like the fact that the Auzen X-Fi Prelude 7.1 allows digital input. This should, in theory, allow the PC to decode compressed format streams like Dolby Digital or DTS. This is a nice value-added feature for those who are into home theater and do not feel that their standalone decoders can reproduce the sound with sufficiently high fidelity.

However, as of this moment, there is no support for Dolby Digital, DTS and such, although support for these formats have been planned for the future. I would have very much preferred that Auzentech shipped the card with support for the formats above, but I acknowledge the fact that Auzentech wasn't sneaky about it and did post very clearly on the front of the box that support would be available in the future.

The output also comes with TOSLINK, which is an optical version of SPDIF. I'm sure home theater enthusiasts would like it. All you need to do is to plug in the supplied adapter and hey presto! you can use any TOSLINK cable with it.