Asus Xonar Essence One MUSES Edition
Device Type: Digital to Analog Converter, Headphone Amplifier, Preamplifier
Input: Coax S/PDIF, Optical S/PDIF, USB Audio Class 2.0
Output: RCA (single-ended), XLR Balanced, 1/4" Headphone jack
Dimensions (H x W x D): 60.65 mm x 230 x 261.33
The Asus Xonar Essence One comes in three versions; the standard ($599), the One Plus Edition with Op-Amp Swap Kit ($699), and the unit under review the MUSES Edition (footnote 1) so named for its use of the MUSES 01 Op-Amps from New Japan Radio Co. Ltd. While I wouldn't call the Xonar Essence One MUSES Edition inexpensive at $899, I would say it leans toward the budget side of things, all things considered. With very solid build quality, a 24/192-capable Asynchronous USB input, two S/PDIF inputs, a preamp, a headphone amp, and optional "Symmetrical 8X upsampling", Asus has thrown a lot into the Essence One including the muses.
The Xonar Essence One's DAC is based on the TI PCM1795 (which is DSD-capable but Asus has not made use of this feature) combined with the C-Media CM6631 USB receiver (the same as used in the recently reviewed Schiit Bifrost). The S/PDIF inputs pass through an AKM AK4113 receiver before getting handed off to the TI DAC. The Xonar will play all standard resolutions up to 24/192 bit perfect through all inputs or with the push of the front-mounted Unsampling push button, upsample all incoming data to 32/352.8KHz or 32/384KHz depending on the original sample rate (i.e. 44.1KHz/88.2KHz/176.4KHz input gets upsampled to 352.8KHz, and 48KHz/96KHz/192KHz gets upsampled to 384KHz). Asus refers to this as "Symmetrical Upsampling" since the original sample rate is used to determine the upsampled rate as opposed to upsampling everything to the same sample rate regardless.
The remainder of the front panel is self-explanatory with a Power button, Mute, Input Selector, two volume controls one for the RCA/XLR output and one for the 600ohm headphone amplifier. There are also LED indicators that light up the corresponding sample rate when Upsampling is not in use. Around back things are also straight forward and include the USB and S/PDIF inputs, RCA and XLR outputs, and IEC input for the included power cord. I find the Essence One to be a nice looking piece of kit with a very solid feel and that cool "Chime of Tiger" tattoo-worthy totem up top.
You probably know that Asus is the world's fifth-largest PC vendor by 2011 unit sales (according to Wikipedia) so its interesting that they've decided to build this MUSES Edition, "generating bigger, bolder, and livelier sound to meet the highest audiophile standards" according to their press release. From the same press release:
“We’ve been constantly looking for well-designed audio devices to really make MUSES shine, and found the ASUS Xonar team has the expertise to create them. What really impressed us was their focus on the digital, PC-based audio realm”, said Ichiro Kashiwagi, Second Marketing Department Manager, Semiconductor Sales and Marketing Division, New Japan Radio Company.And:
Operational amplifiers, or Op-Amps, serve to amplify analog signals and define tone, treble, and timbre. MUSES 01 components are notable as the first to use oxygen-free copper interconnects, allowing for better circuit conductivity and thus improved reproduction. They use exclusive fabrication techniques, including advanced symmetry die-bonding, a custom layout that lowers component crosstalk and generates better-balanced left/right channel symmetry. It is one of the main features responsible for the wider sound fields offered by Xonar Essence One MUSES Edition.So the MUSES OP-Amps were chosen because they sound good and we'll soon see about that. I used the Essence One MUSES Edition mainly via its balanced outputs with the PASS INT-30A so that I could take its preamplifier for a spin. The rest of the front-end consisted of my MacBook Pro running Pure Music and the AudioQuest Carbon USB Cable connected to the MUSES. Since I used a Mac no drivers were required. PC users will need to download and install the ASIO drivers from Asus to get bit perfect playback above 24/96.
Let's get back to one of the Essence One's I'm not reviewing for a moment—the One Plus Edition with Op-Amp Swap Kit. It's worth highlighting the fact that Asus is saying that different Op-Amps produce a different sound and fairly unusual that a company will give you the ability to pick your favorite from a bunch of choices (five). It also speaks to their PC-background that this swapping involves opening up the unit, pulling out and putting in chips. Most manufactures want to ban you from their products inner secrets whereas Asus is inviting you in. It's also interesting that Asus determined, through listening!, what they felt was the best Op-Amp and offered this version as the premium based on the MUSES 01 Op-Amps from New Japan Radio Co. Long live listening (to muses)!
The Sound of MUSES
The Asus Xonar Essence One MUSES Edition has a liquid-sounding mid-range. Now you might think that says it all but it doesn't. And that's because the stuff going on around the mid-range effects how said mid-range sounds. The MUSES' high frequencies are very warm without even a hint of digital glare. I tend to say sweet so I'll also stick with that descriptor as well. The MUSES bass is deep, tight and very tuneful so you're hearing the body of the notes not an emphasis on fingers or boom and bloat. Overall it's a nice balanced round sound.
I'd also say the MUSES gets the mid-range pretty darn near right at least according to my ears and brain and smile (you could say I agree with Asus). I judge rightness by my reaction to listening to music and here the MUSES delivered all of the emotion of everything I threw at it and its especially adept at presenting vocals, you know people singing, in a captivating manner. Music sounds rich and inviting and this makes me want to listen more. I also listen differently when I'm in complete enjoyment mode, taking delight in what the musicians are doing as opposed to taking delight in what the hi-fi is doing. And I found myself going from album to album as opposed to skipping from partially played track to partially played track. The MUSES had me getting into my musical choices completely lost in their charms so much so that I did not want to stop.
This generously musical presentation held when using the MUSES internal preamp and I did not notice a notable difference between it and the Pass INT-30A's preamp. I'd say you could be very happy letting the Essence One MUSES handle preamplification duties if you don't need any analog inputs. A remote would come in handy (Asus does not offer one) but I'm not married to remotes and view them as a nice-to-have option as opposed to a need-to-have feature. The headphone amplifier drove my Audio Technica ATH-W1000s with ease and all of the sonic traits I've described so far hold for the headphones as well. The Essence One also does a good job of resolving low level detail and this is readily apparent through the headphones. One functional feature worth noting is connecting your headphones does not mute the speaker output which makes the dual-volume control make more sense.
With upsampling engaged, the physical presentation grew in every direction (wider, deeper, taller) and you felt a clearer sense of the space of the recording, more drama. I also noticed a change in higher frequencies like cymbals which sounded clearer and better defined. Overall there was a greater sense of resolution at the expense of some of that mid-range fullness and body. With upsampling engaged the mid-range became less sonically important because other parts grew in importance so I liked upsampling for some recordings and preferred it disabled for others. Since this switch is accomplished with the push of a button, selecting a favorite can be as fickle as you and your music like.
If there's something the MUSES does not do that other DACs do is the super-clarity thing. The über-attention to sonic details and edges is just not as crisp and sharp as it can be with other DACs. But, this typically comes at the expense of a rich tonal palette which the MUSES offers in spades and then some and I did not feel a lack of detail or resolution with the MUSES. I'd almost go where I don't normally like to go which is to suggest that people who enjoy vinyl may appreciate what the MUSES has to offer. That's not to say that it sounds like vinyl, it is to say that it does not sound digital.
A Distinctly Pleasing Voice
I certainly enjoyed my time with the Asus Xonar Essence One MUSES Edition. Its rich sonic character is forgiving of digital harshness that can creep into some (most?) recordings and music is served up big, fat and full with a generous helping of tone caressed from every recording. And you're also getting a very nice preamp and headphone amp and if you want you can think of it as getting them for free. If you like your music mid-range rich and on the natural-sounding side, the Asus Xonar Essence One MUSES Edition may be calling.
Footnote 1. The unit under review is a pre-production unit.
Also on hand and in use during the Xonar Essence One review: Schiit Bifrost, Mytek Stereo 192-DSD DAC, Resonnessece Labs CONCERO, iFi iDAC, Chordette Qute HD DAC