What truly makes this card stand out from its predecessors is Auzentech’s choice of components used in the card’s output stages. The use of high quality components, optimized board designs, circuit layouts and attention to detail is a hallmark of Auzentech products and the Prelude is no exception. We shall examine the entire output chain to show the reader what they can expect in their new card.

DAC- Digital to analog converters are very important for the overall sound quality of the card and Auzentech chose to use four high quality AKM-4396 192kHz 24-bit ∆∑ multi-bit DAC’s. This chip offers pristine 24/192 playback at an incredible 120db dynamic range with Total THD+N -100db This converter has been referred to by some as a “Miracle DAC” and offers low out of band noise and resistance to digital clock jitter.

ADC- Analog to digital converter is used for analog input into the card through microphone and line in devices. The card is outfitted with an AKM-5394 high resolution 24/192∆Σ ADC. Featuring a SNR 123db and S/ (N+D) 110dB and High Performance Linear Phase Digital Anti-Alias filter. The Auzen Prelude 7.1 input section is more the suitable for the home recording artist looking to lay down some new tracks.

AKM4396 DAC Spec Sheet
AKM5394 ADC Spec Sheet

Operational Amplifiers are the final stage for a soundcard and changing the cards opamps seems to be all the rage with PC audio enthusiast as of late. Many people have realized that by using better then stock or higher quality opamps you can increase the overall sound quality outputted by your soundcard. A lot of companies will use the opamps as a place to cut on costs of the card and use generic “Jelly-Bean” amps, aptly named for the quantity received for the price, you get handfuls for pennies. It is very unfortunate some manufactures use cheap opamps as this is the final stage of the card and is crucial to maintaining an overall high sound quality for their products. Auzentech decided to use high quality audio amps throughout the cards design. The Prelude features the relatively new National Semiconductor LM4562NA Audio opamp for the Prelude’s stereo channels and four Burr Brown OPA2134 audio opamps for the remaining channels.

This operational amplifier is very new to the audio market but has gained wide acceptance among PC audio and DIY audio aficionados alike. The chip has a very linear response across the spectrum which results in a very neutral sounding amplifier without added colorations or distortion commonly found in otherew sound card designs after finding wide acceptance among X-Meridian owners and “Classic” X-Fi owners alike. The graph above shows the very low THD+N% across the spectrum. THD+N is the Total Harmonic distortion + No lesser amplifiers. It has been used in quite a few nise present in the component. Lower values are better as any distortion or noise is bad but there is always a small amount.

This amplifier is very well know and very well utilized in everything from DIY headphone amplifiers to modern consumer grade audio units. This amp has a very classic “laid back” sound with good bass and nice mid and glossy high range. These amps are very clear and analytical. Offering low distortion with a THD+N of ~0.00008% the combination of both amplifiers should yield a product of amazing sound quality when compared with competitors’ products and existing competing PC audio products.

Additional Components

The card also contains 64 MB of X-Ram. This ram is used as a buffer and holds audio samples for faster loading in newer games. There are a few games using it right now and game developers should continue to take advantage of the hardware.

The X-Fi Processor is a 20KX series Digital signal processor and is covered by a heat sink I didn’t want to remove for fear of damaging the card itself.