First of all, I would like to thank Aune (@AuneAudio) for giving me the opportunity to review their unit.
This is the link to the relevant head-fi thread: https://www.head-fi.org/threads/fin...dsd-128-dac-amp-worldwide-review-tour.830399/
I would like to mention that I am not affilitated to the Aune company in any way.
Associated Equipment, including Hardware and Software
Not a lot changed after the Aune X1S review. Anyway, these are my setups.
Dedicated Mini PC with Intel Atom D510 1.66GHz (dual core, Hyper Threading)
Hardware: Supermicro X7SPA-H mainboard
Hardware: Linear PSU from italian brand ZetaGi (set @12V)
Hardware: 1x1GB + 1x2GB RAM
Software: Currently running Ubuntu Server 16.04, 64bit, Generic Kernel
Software: MPD (Music Player Daemon - http://www.musicpd.org
Software: UPMPDCli (Upnp Renderer plugin for MPD - http://www.lesbonscomptes.com/upmpdcli/upmpdcli.html
Gustard U12 USB Interface
Gustard X12 DAC
Gustard H10 Headphone AMP
Yulong D200 DAC / Headphone AMP
Aune X1S DAC / Headphone AMP with its own XP1 linear power supply
Linux Mint 18.2 'Cinnamon' desktop PC, used to run GMPC/Cantata as MPD clients and Upplay as UpNP control point
BubbleUpNP on Android as UpNP control point
Another Debian-based Linux box is dedicated to file sharing (via Samba and via MinimServer, a UpNP server)
USB Cables: Audioquest Cinnamon 0.75m
HDMI Cable (I2S), used for the comparison with Gustard U12/X12/H10: Ricable HDMI Supreme F1
Balanced Cables, used for the comparison with Gustard U12/X12/H10: Neo By Oyaide D+ XLR
RCA Cables: Wireworld, Amazon Basics
Headphones and Speakers
Sennheiser HD800 (stock cable)
Sennheiser HD650 (with additional XLR cable)
Sennheiser Momentum On Ear
Yamaha HP-3 (Orthodynamic, modded)
Q Acoustics Concept 20
I have connected the Aune S6 to my dedicated PC via USB. Also, I have tried a AudioPhonics 5v LPS for USB power, with pleasant results. Not every DAC benefits from a dedicated LPS, because not every DAC draws power from the USB host. This one does. It seems to me the dedicated LPS can improve performances. I did not do any specific measurements, but what I can tell is that I have experienced in the past how a noisy usb power can harm the functionality of a DAC.
I also would like to mention tha, as usual, no drivers are needed on Linux.
In case someone wants to connect the S6 to a linux os, please note the name of the device is "DAC".
I tend to use upsampling with sox on mpd, tipically to 352.8kHz and 384kHz.
At the Office
Same old Linux PC with Intel Core2Quad Q6600 @office, also used with MPD (Music Player Daemon - http://www.musicpd.org), sox, upmpdcli, upplay.
Headphones: Sennheiser HD650 with a balanced cable.
I listened as much music as I could in the limited time available. Here are the albums I'd like to specifically mention:
- Dire Straits - Brothers in Arms
- Miles Davis - Kind Of Blue (from HDTracks, stereo version)
- Metallica - The Black Album
- Eric Clapton - Unplugged
Please not that I did not listen to the HD800 with the S6 in balanced mode as I do not have a cable yet.
- Deeper (but not bloated) bass
- Lots of power (this kind of explains previous bullet)
- No harshness to my ears, at least after 2-3 hours of listening.
Be prepared for 2-3 hours of not-so-exciting listening time, so I would advice to allow some burn-in time when possible.
The listening has been very pleasant. I enjoyed the bass definition, which probably comes from a great reverse of power.
Also, the mids have always been good and I never heard any harshness on the highest frequencies.
My only complaint is I could not properly test this dac/amp with the HD800 in balanced mode. I hope I will be able to fill this gap soon.
I have compared the S6 against the following two setups:
- The Aune X1S
- The Gustard U12/X12/H10 stack
Both the X12 and the X1S use ESS chips. The X12 adopts the 9018, while the X1S adopts the mobile version 9018k2m.
The Aune S6 adopts a DAC chip from a different brand: the AKM AK4495 from Asahi Kasei.
Detailed specs of the S6 are available on the aforementioned Aune forum post. As I have done with previous reviews, in order to avoid mistakes and misunderstanding, I prefer not to duplicate technical specifications here.
Against the Aune X1S
Quite easy to imagine, this is not a fair comparison. The S6 is superior in quite every aspect. This consideration is not in any way intended to be detrimental to the X1S.
Simply, these two products belong to different price ranges, and the different in audio quality is well audible. That said, I still own and enjoy the X1S in my setups.
Against the Gustard U12/X12/H10 stack
It has been very difficult to compare, especially because I feel using the HD800 with the single ended cable on the S6 would not have been fair.
I can say I have compared the HD650 single ended from the U12/X12/H10 against the HD650 balanced from the S6.
Despite a higher price, I feel the S6 can get very close to the Gustard Stack. We also need to consider the S6 is not burned-in as the Gustard stack is. Also, the H10 has been upgraded with Burson Supreme Op-Amps (both single and dual), for a great improvement.
Both of the setups rewarded me with very nice sound, with no harshness whatsoever, with great definition and great control. In terms of raw power, the S6 seems to have an advantage here.
Why would I want to buy it?
Because it's a very nice dac/amp, remarkably powerful, and because I want a balanced headphone out
It has a variable output so I can also think of connecting a speakers power amp (meaning, with no pre-amp section)
I really liked the Aune S6 and I want to thank Aune again for the opportunity and the patience.
One thing that is IMO left to be desided by this unit is the lack of a I2S input. If you have a DDC like the Gustard U12 or the now very popular Singxer, you might want to use the I2S of such interface, but the S6 has no I2S input.
You can use the coax, aes/ebu or the opt input, but those kind of connections are limited to 192kHz max (this happens on almost all DACs I know of, with the notable exception of some Chord DACs).
Of course this is not a showstopper: the usb input is really fine, and can be improved with dedicated LPS as well as with some "jitter eliminator" devices, like, for example, the Schiit Wyrd.
Another minor glitch IMO is that you do not have the option to output to headphone and line outputs at the same time. However, I understand why it is designed like that. In most use cases, one does not want to ear speakers when listening to headphones.
So in conclusion, I would safely advise a friend to buy this DAC/Amp and I would be sure he would not complain.
Great work, again. Kudos to Aune.