ASUS Xonar Essence STX II 7.1 Soundcard Review

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ASUS Essence STX II 7.1 Soundcard Review


The quality of audio devices has improved dramatically in recent times, particularly when it comes to providing excellent HiFi quality at affordable levels. This, coupled to the ease of having vast digital audio collections, has lead to more of us having high-end audio headphones or speakers, and the accompanying audiophiles such quality brings. So what if you need to make the most of your setup and demand absolute audio perfection regardless of cost?

Cue the ASUS STX II 7.1 sound card. The sequel to one of the finest audiophile sound cards on the market. Back in 2009 the market was in a state of flux with Creative suffering hideous driver issues leaving a yawning chasm just waiting for another manufacturer to fill, and the Xonar range from ASUS beautifully filled that gap. There were a massive bunch of cards to choose from but if you wished for only the finest audio quality then the Essence STX was the one to go for. You did have to purchase an additional break-out card to allow things other than studio headphones to be utilised and that's where the STX II really comes up trumps. 

With the full specifications available here, if you're interested, it's better to give a brief overview, as the STX II does so much we could take up half the review space with numbers many people don't fully understand.

Industry-leading 124dB SNR (signal-to-noise ratio) audio quality inherited from the Xonar Essence ST/STX
Ultra-low jitter with premium TCXO clock source
Clean and consistent power supply thanks to high-fidelity low-dropout (LDO) regulators and WIMA® capacitors
Headphone amplifier supports up to 600ohm-headphone impedance with additional gain for in-ear monitors
Exclusive op-amp swap kit includes 3 op-amps and tool for easy tone tuning (Texas Instruments LME49720s and one MUSES 8820)
Celebrated MUSES op-amps deliver true-to-life musicality
Ultra-fidelity (120dB SNR) 7.1-channel output via the daughter board

Up Close

The packaging for the STX II hints at what a high end product this is. No fancy graphics, no unexpected colour schemes, just a solid box with a clear design ethos. Inside, apart from the two elements to the STX II itself, there are three additional OP-AMP changes - Texas Instruments LME49720s and a MUSES 8820 - allowing you to fine tune the audio reproduction for your particular tastes. 

ASUS Essence STX II 7.1 Soundcard Review     ASUS Essence STX II 7.1 Soundcard Review

ASUS Essence STX II 7.1 Soundcard Review     ASUS Essence STX II 7.1 Soundcard Review

  ASUS Essence STX II 7.1 Soundcard Review     ASUS Essence STX II 7.1 Soundcard Review  

   ASUS Essence STX II 7.1 Soundcard Review     ASUS Essence STX II 7.1 Soundcard Review  

ASUS Essence STX II 7.1 Soundcard Review  

As you can see the various add-on cards of old which had to be purchased separately have all been merged into a single PCIe soundcard replete with all the connectivity you could hope to have, especially if you're in the market for a high quality surround sound experience.

Beneath that lovely EMI shroud is found the heart of the Essence STX II. There is a TI PCM 1792a DA converter, MUSES OP-AMPs, WIMA capacitors and the celebrated Texas Instruments TPA6210A2 headphone amplifier. Wherever you look the ASUS STX II is stuffed with the highest quality parts to bring a whopping 124db SNR clarity through speakers, and 120db when utilising headphones. All of this is kept in perfect synchronisation with a temperature controlled crystal oscillator.



There are likely to be two main audiences for the ASUS Essence STX II; Audiophiles, and those seeking only the best possible products in their system.

Which category you fall into depends largely upon how much sense you made of the above. If you were gasping with joy at the knowledge that the STX II utilises MUSES amps then you know already that every single item on the check list has been fulfilled and should immediately rush out and purchase one.

If you didn't grasp much of it but are sick of the audio you're currently experiencing then we can assure you that you wont find a better quality sound card on the market. Of course it's incredibly expensive but if you own a suitably high quality set of speakers or headphones the difference is astronomical. Everything sounds exactly as you'd wish it to do, with a clarity of definition that left our mouths open every single time we pumped our media of choice through it.

The inclusion of three OP AMPs and the 7.1 daughter board means that you can install a baffling array of audio devices into the STX II and then fine tune the output until you are as satisfied as a duck who lives outside a bakery. Everything from low to high impedance headphones, studio monitors and regular surround systems is supported.

The ASUS Essence STX II 7.1 Soundcard is aural nirvana and if you have even the slightest interest in high quality sound you should seek one out. Unquestionably excellent and an easy winner of our OC3D Gold Award.

Discuss the ASUS Xonar Essence STX II 7.1 Soundcard Review in the OC3D Forums.  

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Most Recent Comments

07-11-2014, 15:53:09

no expense spared that's the worrying bitQuote

07-11-2014, 16:29:38

enjoyed the review and loved the comment about the names I agree why do they name them with such hard names Quote

07-11-2014, 16:46:19

I have the stx, I best get saving for this one then.

On mine I have the hifi mode enabled, it acts like a pass through, not interfering with whats being played.
I let the 828k deal with the crossover level, its set at 80hz.
With the front speakers bi amped, then running the sub in plus mode, so bass is going to all 3.Quote

07-11-2014, 17:04:13

Big Boss
I've got an X99 Deluxe, planning on getting a pair of AKG K702's predominantly for gaming, but will listen to the odd bit of music through them via YouTube/spotify. Is it worth getting this souncard for that bearing in mind there a pair of a high end reference headphones, with a 62 ohm impedance.

Also, what PCI lane can you plug this in to? My graphics card blocks my x4 slot, can it be inserted into a x16 lane?Quote

07-11-2014, 17:06:22

AHHH THEY STILL USE F****** MOLEX!!!!!!!!!!!! My current Xonar STX uses them, so that means I have to use my RM650 molex cable to attach just ONE device. And there is NO way of hiding that damn cable!Quote

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