ASUS Xonar Essence One Muses Edition D/A processor–headphone amplifier Specifications

Sidebar 1: Specifications

Description: Upsampling, stereo D/A processor/headphone amplifier with independent volume controls for line-level and headphone outputs. Digital inputs: 1 S/PDIF (coax), 1 S/PDIF (TosLink), 1 USB 2.0 (type B). Analog outputs: 1 pair balanced (XLR), 1 pair unbalanced (RCA), 1 headphone output on ¼" (6.3mm) stereo phono jack. Compatible sample rates: 44.1–192kHz, all inputs. Frequency response: 10Hz–48kHz, –3dB, with 192kHz data. Channel separation: not specified. Signal/noise: 120dB ref. 0dBFS, A-weighted. THD+noise: >0.000316% (–110dB) at 0dBFS. Maximum output level: 2V single-ended, 4V balanced, 7V headphone. Jitter: not specified. Output impedance: not specified. Power consumption: not specified.
Dimensions: 10.3" (261mm) W by 2.4" (61mm) H by 9" (230mm) D. Weight: not specified.
Serial number of unit reviewed: C9YAAJ000453 (firmware v.127 & v0111).
Prices: $899, Muses Edition; $599, standard edition. Approximate number of dealers: "well over 5," including Amazon and NewEgg.
Manufacturer: ASUSTeK Computer Inc., 15 Li-Te Road, Peitou, Taipei 11259, Taiwan. US distributor: ASUS Computer International, 44370 Nobel Drive, Fremont, CA 94538. Tel: (812) 282-2787 (support). Fax: (510) 608-4555. Web: usa.asus.com.

COMPANY INFO
ASUSTeK Computer Inc.
US distributor: ASUS Computer International
44370 Nobel Drive
Fremont, CA 94538
(812) 282-2787
ARTICLE CONTENTS

COMMENTS
rockoqatsi's picture

And in any case, I think it's great that you're reviewing these entries from ASUS (this, and the Xonar ST), though I'm surprised to find them releasing such an expensive and esoteric item—for a motherboard manufacturer at least. How good have dacs in the $700-$900 range gotten since the Lynx cards were a hot commodity? Any idea? (I'd try selling my Lynx for the Benchmark DAC2, but nobody wants a legacy PCI card these days.)

trl's picture

I know this is an old thread, but I really want to say that the final sound from a Hi-Fi device has indeed a correlation with how good or bad it measures. Going to provide some examples below:
- The "oversampling inband noiseshaping" was caused by a bad firmware existing inside all MKi Essence One DAC versions. The MKii version (the one supporting DSD playback) has a newer firmware available for upgrade that resolves this issue, so graphs from above are true for the MKi ver. of the E1 DAC (MUSES or no MUSES, same thing happens).
- The 120 Hz "spurious tone" was caused by the EMI created by the toroidal transformer. Issue can be resolved by leaving the DAC with case open (yes, the EMI bounces from the metallic case back into the motherboard and PSU) or by shielding the toroid with Grain Oriented Silicon Steel or similar EMI shielding steel. The 120Hz issue can also be measured with a scope, but can also be heard with very sensitive headphones connected on headphone-output 6.3mm plug.
- Jitter and noise levels can be dramatically improved by separating both DACs power lines from the main PSU and create a small +5V PSU only for the DACs (cut the PCB traces nearby the 1795 DACs and connect the new +5V PSU). This DAC has no separate +5V regulator nearby the DAC chips and the original +5V/1A regulator is powering the entire PCB including the ARM chip from inside that is also very noisy, polluting the entire +5V rail and this noise reflects in the final sound and in the above measurements (noise and ripple can also be easily measured with a scope connected directly to +5V DAC pin).
- There're ground loops on the +5V and -12V rails (+12V looks fine) that have measurable high ripple and noise. Resolving these 2 ground-loops (by adding thick ground wires or by replacing or upgrading the PSU) will resolve the "grainy" sound and also decrease the noise and jitter.

So yes, if an audio device is measuring mediocre (or even worse) then it will also sound mediocre (or worse, ofc) and this is why bad measurement results usually reflect a possible technical issue (some can be resolved by firmware, but some not).

P.S.: I'm glad Stereophile is conducting these tests for us!

X