Aune S9c Pro Review
The Aune S9c Pro was kindly provided free of charge in exchange for an honest review. I didn’t receive monetary or any other kind of compensation and I don’t use affiliate links. The price of the Aune S9c Pro is $738 for the Bluetooth version and $699 without it. You can buy them directly from the Aune official store or Amazon USA.
Aune Audio
Aune Audio doesn’t need any introduction, it is a well established brand that has been devoted to developing desktop and portable audio products such as DACs, digital transports, music players, headphone amplifiers and earphones. They are committed to the pursuit of superb sound and great user experience while at the same time keeping their prices as friendly as possible. The brand has been extensively covered by ichos-reviews where you can read reviews for most of their highly acclaimed products like the AUNE X1s GT, Aune X8 XVIII and Aune Flamingo.
Aune S9c Pro
Aune S9c Pro
The Aune S9C PRO is a brand new all-in-one DAC and headphone amplifier that can also be used as a volume controller with active speakers. It is available in two editions with or without Bluetooth wireless connectivity. The Bluetooth version supports the LDAC, aptX and aptX HD, high resolution codecs.
Among the 1080 discrete components that are used inside the S9c Pro, Aune has integrated high-end audiophile components such as two ES9068AS DAC chips in a fully balanced configuration and a separate USB XMOS interface, enabling it to decode up to PCM 32bit/768kHz, DSD512 and MQA 16x.
The use of ultra-low jitter PLL (phase-locked loop) technology enables the S9c Pro to isolate the clock source signal from the analog input signal, and transmit it simultaneously to the USB XMOS interface and the DAC section. It’s this sharing of the clock signal source that makes high-fidelity rendering possible. But the special feature of the S9c Pro is that the clock synchronization system also converts coaxial, AES and optical signals into I2S signals, greatly enhancing the quality of the final audio rendering and drastically limiting interference. The S9c Pro also supports a 10 Mhz BNC input for an external clock like the Aune S1c, SC1 and XC1.
The balanced amplifier stage is a discrete circuit with the integration of 16 dual JFET transistors (2 per output channel) enabling it to deliver up to 5W of power. The amplifier features 3 headphone outputs, 4.4mm and 4-pin XLR balanced plus a single-ended 6.35mm jack.
The unit is powered by a 50W toroidal, low ripple, transformer with 23900μF of total capacitance and a linear power supply with separate regulations for all critical parts of the board.
You can read everything about the Aune S9c Pro here.
Two tuning modes
To pursue better sound, Aune has specially developed two tuning modes with their own algorithm rather than relying on the embedded low pass filters of the DAC chip. MODE 1 is the standard mode where the S9c Pro works in the state of fast locking and low latency. The sound is neutral and natural. MODE 2 is the pure mode where the high performance PLL provides more precise clock signals. In this mode, the performance of the DAC is improved with higher sound density and better soundstage.
Build quality and appearance
The Aune S9c Pro is quite compact and suitable for desktop use. The chassis is made from aluminum that helps to further isolate the circuit from electromagnetic interference. The unit is sturdy and very well made with a fine sand-blasted finish that is available in black and silver.
The S9c Pro adopts the Aune trademark arc-shape design which is classic, simplistic and beautiful looking. The only disadvantage is that when you stack two units together, like the S9c Pro and the S17 Pro headphone amplifier, there is a visible gap at both sides and the top device is not so stable.
Aune S9c Pro – back panel
User interface
The front face of the Aune S9c Pro is clean and minimalistic, the center is dominated by the generous LCD display which has good visibility and is easy to read. At the right side there is an aluminum multifunction knob and at the left the three headphone outputs. At the back of the unit you will find the AC plug, the on/off switch, coaxial, optical, USB, BNC and AES digital inputs, the Bluetooth antenna socket and the analogue outputs, XLR and RCA. The unit doesn’t have a standby mode, it can only be switched on and off from the switch at the back and it doesn’t have a mute function.
You can control the device with the multifunction knob: turn left and right to adjust the volume, single press will cycle through the digital inputs, double press will switch between headphone or line output and continuous press will switch between the two audio modes. All operations are also available through the aluminum remote control that is included in the package. The screen displays all necessary information such as digital input, sound mode, volume, sampling rate, and the selected output. The line output volume adjustment is variable and cannot be fixed, you need to reach the 100 mark setting for the full voltage swing while line and headphone outputs have their own individual volume settings that are remembered by the unit.
On a side note, what I really like is that there is a cheaper version of the S9c Pro without Bluetooth wireless connectivity so the user doesn’t have to pay for a function that is not going to use. Personally I dislike Bluetooth sound and never use it, so I prefer to have all my audio devices without a Bluetooth module.
Aune S9c Pro & Lavricables power cord
Accessories
The Aune S9c Pro comes with an AC power cord, a high quality USB cable, a 6.35mm adapter and the aluminum remote control.
Power output
The headphone amplifier of the Aune S9c Pro is very powerful and can drive both high and low Z headphones with ease even if they are of low sensitivity. The volume adjustment ranges from 0 to 100 so you can do fine adjustments and use headphones. Very sensitive earphones, like the Soundz Avant, are not recommended because there is an audible noise floor. With everything else that I have tried, the amplifier was silent. To get a rough idea of the headphone amplifier power output you should know that the Meze Empyrean was loud enough at 45 and for the HIFIMAN Susvara I never passed the 80 mark. As per usual practice, the Aune S9c Pro was burned for about 100 hours before listening evaluation.
If for some reason you need more power or you want to taste how a Class-A fully-discrete headphone amplifier sounds, you can add the Aune S17 Pro which can do a whooping 7W+7W/32Ω from its balanced output. (stay tuned for the upcoming review).
Aune S9c Pro & S17 Pro
Associated gear
I used various headphones, like the iBasso SR3 and the Focal Clear Mg but after a while it became pretty obvious that the Aune S9c Pro has the potential to mate with much better headphones so I switched to the Meze Empyrean with the Angled pads. To test the line output of the S9c Pro I hooked it to a 2-channel system that consists of the Lab12 integre4 MK2 amplifier and the Audio Physic Spark speakers. Streaming duties were entrusted to the Volumio Rivo. The power cords, USB and all headphone cables are exclusively made by Lavricables .
Listening impressions
Musical, engaging and captivating is the Aune S9c Pro and you don’t have to listen a lot in order to understand how much effort was put into fine-tuning the device. This is not the usual, mass produced Chinese DAC/amp with the latest chips and the same topology that is used again and again without much inspiration and thought just to measure well in the lab. The S9c Pro is an “old fashioned” audiophile design where the engineer cares about sound and timbre realism and it is pretty obvious that has spent hundreds of hours to commit his vision into actual music.
And don’t even think that the Aune S9c Pro is not technically skillful or lacking in what we call “technicalities”. Frequency response is absolutely linear, the sound is transparent and crystalline with excellent clarity and definition throughout the whole frequency range. The bass is tight and controlled, full bodied, weighty and visceral with ample dynamics and physical impact. The mid-range is spacious and open sounding with surplus of resolution and refinement as is also the treble which is extended, energetic and detailed but without the usual ESS shrillness, brightness and analytical character. The soundstage is spacious and extended with sharp imaging and a well organized and impressively holographic relief.
I have lately reviewed many audio devices with the ES9068AS DAC chip (or even the ES9038PRO) and I must admit that the Aune S9c Pro is one of the least digital sounding while it has the most natural and smooth treble among many of them. This is not a coincidence though because Aune have gone into the effort to write their own low-pass algorithms and design a discrete headphone amplifier, specifically for making the S9c Pro to sound natural and realistic. This is the kind of audio device where you start listening to music and forget about everything else, you don’t have to think why the sound is bright, unnatural or artificial, the S9c Pro is about pure music and nothing else.
The Aune S9c Pro is extremely colorful and harmonious, expressive, organic and musical, almost analog sounding like there is a tube stuffed inside or using some class A topology. The S9c Pro is versatile when it comes to headphone matching and the only thing you have to do is to choose the right one according to the music you are planning to enjoy. With the Meze Empyrean (angled pads) they made a match made in heaven and produced extra realistic and natural sounding instruments with stunning vocals. Classical music is the forte of this combination and the Aune S9c Pro is highly recommended as one of the least expensive audio devices that can offer a taste of the high-end sound.
The line output
If there is something to criticize about the Aunes S9c Pro is that although the sound quality of the line output is very good, it is not up to the level of the headphone output. Don’t get this wrong though, it is not that the line out is not competitive or enjoyable but the truth is that there is a slight loss of musicality as discussed earlier and the sound now reminds more of a typical ESS implementation as commonly found elsewhere. It is a little bit more clinical and more concentrated in technicalities rather than musicality, so in this regard you have to use the headphone output in order to enjoy the Aune S9c Pro in its full glory, at least if timbre realism is what you care for.
Aune S9c Pro & Meze Empyrean
Compared to the FiiO K9 PRO ESS ($849)
The FiiO K9 PRO ESS is FiiO’s flagship desktop DAC/amp that uses two ES9038PRO DAC chips in a fully balanced configuration and dual THX AAA 788+ modules for the amplification duties.
The FiiO K9 PRO ESS has half the power output of the Aune S9c Pro at 32Ω but the different volume curve makes it more powerful for 300Ω loads while it is more suitable for sensitive earphones thanks to the gain settings that allow for less internal noise. The FiiO K9 PRO ESS has wireless Bluetooth connectivity as a standard and it also supports balanced and unbalanced analog inputs so it can be used as a standalone headphone amplifier. A function that is missing from the Aune S9c Pro, and this is a shame when we consider how good the amplifier stage is. Another difference is that the S9c Pro supports AES digital and BNC clock inputs that are not present in the FiiO K9 PRO ESS.
Aune S9c Pro & FiiO K9 PRO ESS
Regarding the sound signature differences, the Aune S9c Pro is more musical and organic sounding with less artificiality in the treble, it has a fuller, more visceral texture, greater dynamic impact and more holographic soundstage. The FiiO K9 PRO ESS on the other hand, has better technical performance, it is cleaner, more transparent, detailed and resolving but also a touch more clinical and not as emotionally expressive.
In the end
With an audio performance that far exceeds the asking price, the Aune S9c Pro represents an outstanding value because it is the most affordable DAC/amp in the market that can give you a taste of real “high-end” sound.
Aune Audio is a Chinese audio brand that deserves a great applause for not following the easy path and taking great effort to design and tune the S9c Pro in order to produce music full of sentiments and emotions backed by some strong technical performance.
Copyright – Petros Laskis 2023.
+ The sound is extremely musical and organic + Great timbre realism and lack of artificiality + Crystal clear and transparent + Excellent technicalities + Expanded and very holographic soundstage + Powerful headphone amplifier + Large LCD display + Fully functional remote control + Three headphone outputs + Variable line output + External clock support and AES digital input + You can buy the version without the Bluetooth module for less money + Excellent build quality + Relatively compact + Supreme value for money - Power on/off switch is located at the back - No mute and standby functions - An analog line input is missing - Can't switch the LCD display off - Not recommended for very sensitive IEMs - The sound quality of the line output is slightly inferior than the headphone out
Hi
Have you heard better than this dac/amp?
And thanks for your review.
Thank you for reading. This is one of the best I have heard and for the price is a real bargain.
Hi Petros!
Thank you for review! I have just one question: in sound comparison with the FiiO did you mean the headphone outputs or the sound on the speakers?
Hi, thank you for reading!
The comparison is with headphones. The line output of both devices is quite close in performance.
Thank you very much!
When is the Aune S17pro review? 🙂
Probably next week. It is half finished. Spoiler – it is really good….
Hi.
Between the Aune S9c Pro and the Fiio K9 Pro. Which makes a better combination with Arya Stealth?
Hello, I would say that the Aune S9c Pro is a better combination as it adds some body and warmth that are missing from the Arya Stealth.
Hi Petros,
I’m trying to decide between the Aune S9C Pro and the Eversolo Z8 for two-channel hi-fi listening. I believe they are quite similar, with the Aune leading with an outstanding headphone output.
Also a fan of Audio Physic (Classic 20), my collection consists mostly of live video concerts and studio albums.
The Exposure 3510 is my amplifier of choice. Thank you for your valuable insights and great reviews!
Best Regards,
Ilias P.
Hi Ilias,
Thank you very much for reading. I haven’t tested the Z8 so can’t speak for sound quality but it is definitely more versatile for a 2 channel set-up as it includes the streamer. On the other hand, as you have already said, the S9C Pro is very hard to beat at this price point when it comes to the headphone output. So you are called to make a difficult choice. BTW, I am also great fan of Audiophysic, my main speakers are the Spark 6.
Hi mr. Petros! On the HeadFi forum you wrote that you were listening to HifiMan Serenade. Tell me what is better to buy for Aune S9c Pro or Serenade? What are your impressions comparing these two devices? Thanks a lot!!!!
Hi Vladimir,
The Serenade review is a little delayed but soon will be ready. The Serenade offers better overall performance but at a higher price. The star of the show is the DAC which offers sonic performance that is very close to the Gustard DAC R26.
How would this compare to Burson ? I sold mine Burson Conductor 3r and thinking about trying either another Burson or something else .
I guess that you mean against the Playmate 2. They are close enough, both sound organic, musical and analog. The Aune is also cleaner and more transparent than the stock Playmate but if you roll op-amps to the V7 Vivid, then they become at least equal. Still the S9C Pro is more open and expansive with better depth layering. Functionality is also for the Aune as it has better connectivity. Honestly, the Aune is great sound and a bargain for the money paid.
hi petros, I would like to ask you how you would compare the sound of the s9c with the earmen angel and the mojo 2, and I would like your opinion since you have a lot of experience, I own the mojo 2 and the nx4 topping and I definitely prefer the topping, I find it more detailed and the voices are more intelligible, do you think that at this point I might prefer a more analytical sound than an organic one?
Hi Peppe,
Although I don’t have listened to this particular Topping, my experience with other DACs from the brand suggests that you might like more analytical and clean sound. Now, it is not that the S9C Pro is not detailed or is lacking in analysis and clarity but I think that the Angel will serve you better and find it more to your liking.
Thanks!
Ehi Petros! Qual è la tua modalità preferita dell’ s9c?
The headphone output.
sorry, I explained myself poorly, I meant between mode 1 and mode 2, what kind of differences did you notice?
Not much. I think that mode 1 is a little bit more natural sounding and mode 2 a tad better separation and clarity.
Hello, Petros! I have K9 pro ess and already slightly tired of THX apms. How do you think, should i try Aune S9C or just add a Aune S17 pro to the K9 pro ess?
Hi Igor,
I think that the second option should do the trick. The K9 PRO ESS has a direct line output that bypasses the THX amplifiers and you get a crystal clear sound with great technicalities. Then the S17 will add the analog and organic timbre you are after. I have tried the S17 with more sterile sources that the K9 and it has the means to make the sound engaging.
Thank you for your reply. Hope, K9 pro ess + Ifi micro iUSB3.0 + S17 pro will achieve good perfomance. I will refer to your reviews in the future. Perhaps I’ll add my impressions here later. Thank you!
I am pretty sure that you are going to like the outcome. Please share your impressions here.
Hi , I saw a new comment but it is deleted due to a website crash. Can you kindly post it again?
Hello, I am stuck between the Aune S9Cpro and this Fiio K9 AKM as an upgrade from my K7. I am predominantly a listener of Metal and sometimes Jazz/Blues. Metal is not always well produced, especially the older stuff. I cannot listen to the Aune here in Australia, the closest store is 1000km away.
Will the Aune possibly be too revealing and not leave me enough “meat” on the bone for metal music? Is the K9 AKM maybe a little bit richer for crunchy riffs etc?
That bottom end heft and impact on double kick drums in metal is paramount to me but of course I would like a clean non fatiguing sweet top end with a wide stage.
Would in your experienced opinion I be better with the Fiio K9 AKM or Aune S9C pro? … or any other suggestion?
Regards from Australia.
Hi Dan,
Greetings from Greece. I think that the Aune S9C will serve you better. It is richer, with more meat on the bones, fuller low end, more forgiving treble, a bit more organic timbre and all that without lacking in technical performance. Soundstage is also wider, discreet designs always fare better than THX in this regard. Just make sure to use the balanced output.
Hi Petros, Thank you kindly for taking the time to reply – very much appreciated. What you describe in your reply is pretty much what I am after, this makes me pleased to read. The Aune is more expensive but seems will be worth it.
I will be using the XLR or 4.4mm input with my headphones which are Focal Clear and Focal Radiance. I currently have the Verum II on order and do plan on getting some HifiMan at some point, maybe Edition XS or Ananda nano, though I am not sure on them, I’ll have to do some research on them later in the year.
It seems the Aune is not likely to leave me wanting more power in the future no matter which headphone I choose.
I will on occasion hook the Aune my 2ch system as well.
Thank you again for taking the time to help, and kind regards
Dan
*Should read XLR or 4.4mm output with my headphones!
Hi Dan, glad that I helped.
Considering your preferences, I wouldn’t choose the Ananda Nano. If you want something from HIFIMAN, better consider Edition XS, Sundara or Arya Organic.
Thank you again Petros, I will definitely take that advice with me in my research on the HifiMan headphones. I hope to look more at them by the end of the year,
Ciao! come confronteresti s9c pro con il questyle cma 15? senza considerare il prezzo.
Hello, it’s been a long time since I reviewed the CMA15. From memory alone i can say that the Aune has a more organic and natural timbre. It is also a bit warmer and more holographic. The CMA has the technical advantage, better separation, clarity and transparency.
Thanks!
one last question, what is the most neutral and technical sounding dac/amp you’ve tried? in short, the one most studied.
Well, this is difficult to tell because there is not only one. The FiiO R9 and KA19 are good candidates, the CMA 15 and the Violectric V590². SMSL stuff is also very technical and neutral but also maybe a little boring and sterile.
Have you tried the Fiio k19? is the violectric v380² also neutral like these? I have the K19 and although it has a nice sound it seems more on the warm side, I don’t know if it’s a bad impression on my part.
Only briefly, didn’t have the chance for a full review. The sound reminded me of the FiiO R9. Very clean and technical but not clinical or sterile. But I wouldn’t call it too warm. The Violectric is also neutral but the DAC section is a little outdated. Honestly, if you have the FiiO K19, I think that you are covered. Unless you want something absolutely neutral but also clinical and sterile.
I’ll explain my doubts about the K19. Using it with my HD 490 Pro headphones I certainly find it to have a pleasant sound. It has nice powerful bass, a good timbre and a full-bodied sound, but it doesn’t have a good soundstage and also the detail and imaging (for me ) are a bit disappointing, to my ears my little old nx4 topping has a bit more detailed sound. At this point the Questyle cma 15 remains as an alternative, do you think it could be right for me (better detail, more transparency and better soundstage and imaging) or is it not better than the k19 in these areas?
Hi Giuseppe, as I don’t have them to do a side by side comparison, i don’t think that i can help. The CMA15, i remember it as very technical but also a just a bit warm and not sterile. Unfortunately, the only valid way is to try and hear by yourself.
sure, but you still helped me a lot, I think I’ll keep my k19, thank you!
I am glad that I helped.
I Petros, thanks in advance for the great aid you give us with your reviews.
Simple question from Lisbon;
Being a user of the Aune X7s/X8/XP1 for the last 7 years, do you think in doing the upgrade to the Aune S9C Pro I will be rewarded with a better sound quality that justifies the investment?
Despite the S line being a sep above the X line, the Aune X7s/X8/XP2 costs more or less the same as the S9C Pro.
Hi Luis,
The performance of the S9C Pro is just a little better than the stack and you get rid of the bulk. The house sound is the same, the S9C is a bit more clean with better definition and layering. The overall technical performance is a little better. Don’t expect night and day differences but it is something more fresh. Another option is to keep the X8 and add the S17 Pro to the chain. I really like the X8 with the muses op-amp.
Thanks Petros.
That is in fact an option. I would also like to try the R2R sound. Maybe with the new K11, it’s cheap but there´s not much feedback about it yet and I´me not shure about the EF line of R2R. Despite having used the Muses01, lately I’ve been using the OPA2134 more often, don.t know why, just sounds better to me, maybe a more centred sound. The S17 Pro seems to be excellent but do I need that much power, maybe not. I’m using the T50RP MK3 and the HE400Se V2 and plan to upgrade to the XS or the Anada V3/Nano. So many choices so litle money…
The FiiO K11 R2R is very good and I highly recommend it. I am preparing a review of it. I think that it will be a great option as DAC with the Aune amplifier you already have.
I will wait for your review. Let´s see if it can rival with the Himalaya’s. I guess my choice will be between the K11/SR11 and the EF500. Probably a choice not as good as the S9C Pro, but on the other hand its cheaper an honestly, despite the X8 sounded not so cold for an ESS implementation, right now I would prefer a more “warm” kind of sound.
Good auditions.
Thank you.