- Great musical sound, analogue and melodious, not as warm as it might sound on TUBE.
- More vivid sound from OPA.
- Ability to switch the sound between TUBE and OPA without stopping the music.
- Great design, very attractive and compact.
- Remote control and Bluetooth reception possible.
- Supports PCM 768kHz/32Bits, DSD512.
- Very good price/performance ratio for system without Bluetooth.
- High amount of power for low to medium impedances.
- Does not decode MQA.
- No balanced output.
- The volume is too exponential and in the last steps the voltage increases a lot.
- Be careful with the heat of the valve, it can burn. Although this is normal.
Link to the WEB
Aune Audio (Wuhan Ao Lai Er Technology Co., Ltd.) is a brand that was founded in 2004 by 6 co-founders, experts in various audio-related fields, such as hardware design, electro-acoustic design, programming, speaker design and tuning.
The first time I tried an Aune product was not so long ago. I borrowed the BU2 portable DAC/Amp, as well as the iFi Audio xDSD Gryphon. Of the two models, without comparing them, I was most surprised by the BU2. I liked the sound. Soon after, Aune released this beautiful stationary tube DAC/AMP. It was then that I thought it was the perfect opportunity to own a tube device. In fact, I was very fortunate to be able to receive it for review. The Aune Flamingo has quickly become my primary source connected to my PC. I spend many hours typing at my desk and I like to use stationary sources. Also, connected to my PC via USB, the Flamingo is capable of decoding DSD512 natively, as well as files up to 768kHz/32Bits in PCM. It has a coaxial input and an RCA output. There is a model with a Bluetooth receiver, but I’m not a big fan of this type of audio transmission channel, due to its clear limitations. And yes, the Flamingo is a DAC/Amp with a valve, but it is so versatile that it also has amplification via OpAmps and 7 different filters. It has a 6.35mm SE output, a beautiful front end with an oval OLED screen that displays all information clearly and concisely, in white, and an infinite potentiometer. Its chassis is made of aluminium and has a matching remote control with a spectacular minimalist and very attractive presentation. Let’s see what more surprises this great audio device has in store.
As mentioned in the introduction, a Bluetooth model is available. The remote control can be purchased separately. In the links to Amazon, there is an option that includes the Bluetooth model and the remote control.
- USB input: PCM 768kHz/32Bits, DSD512.
- Coaxial Input: PCM 384kHz/24Bits, DoP128.
- Line Output, RCA OPA 2V RMS (max).
- Line Output, RCA TUBE 1.9V RMS (max).
- Line Output, OPA Frequency Response: 20Hz – 20kHz (±0.02dB).
- Line Output, TUBE Frequency Response: 20Hz – 20kHz (±0.6dB).
- Line Output, THD+N @1kHz OPA: 0.0003% @0dBFS Typ.
- Line Output, THD+N @1kHz TUBE: 0.02% -17dBFS Typ.
- Line Output, Noise Floor OPA: 4µV.
- Line Output, Noise Floor TUBE: 20µV@AES17(20kHz).
- Headphone Output, Maximum Undistorted Output: 45mW@300Ω 0.05%.
- Headphone Output, THD+N @1kHz OPA: 0.0005%.
- Headphone Output, THD+N @1kHz TUBE: 0.035%.
The Aune Flamingo comes in an eye-catching square, red box, with a minimalist design of the device on its main side, in white, under the model name. Nothing else. The back of the box is black and its lettering is also white. Only the slogan, the brand name and little else is written on the back. The dimensions of the box are 178x158x95mm. Inside is a card with instructions, following the simplistic line of the product. The Flamigo comes in a whitish protective pouch, protected by a thick black foam rubber mould. Underneath is a black cardboard separating the rest of the accessories at the bottom. In summary, the complete contents are as follows:
- The Aune Flamingo.
- A 12V power supply with European plug.
- One 3.5mm to 6.35mm gold plated adapter.
- A remote control.
- A Torx screwdriver to open the remote control.
- One USB A 2.0 to USB B 2.0 cable, with gold-plated connectors.
- One USB C to USB B 2.0 adapter.
- A branded card.
- Protectors for the RCA outputs.
The accessory set is sufficient, the remote control is great and so is the gold-plated USB cable. Of particular note is the small USB C to USB B 2.0 adapter. I love the minimalist design of the Flamingo.
Construction and Design
This DAC/AMP has the beauty of simplicity. With a full black aluminium body, fully rounded sides, the window design for viewing the valve and its interior colour, as well as the front, with its OLED display, 6.35mm SE headphone output and matching infinite potentiometer, the Aune Flamingo exudes elegance from all four sides. I don’t think there’s a more attractive device on my desk, and it’s not exactly alone. The OLED display is simple, white-lit, with large text, inside a round-sided rectangle on the left side. At the far end of this side is the headphone output. I miss a balanced output, it would have been the crowning glory of a great device. On the right side there is a circular hole that allows you to see the valve tip, next to the infinite potentiometer on the far right. At the top there is a window that allows you to see the valve from the top. The same window is underneath. The product name is at the top of the display oval, above the headphone output, in subtle white ink. Above it is the Hi-Res Audio logo sticker. On the back are, from left to right, the gold-plated RCA output, the coaxial input, likewise, the USB B input connector, the Bluetooth antenna (in case the device is one), the 12V power input and a convenient on/off switch. This side is assembled by means of two Torx screws.
On the underside, in addition to the valve window, there are 4 rubber feet and a sticker with a linear barcode. And nothing else.
The construction is robust, in black aluminium, as is the remote control.
The internal design is hybrid, valve or OPAmp operated. It is not specified which DAC it uses, but it does highlight that it uses WIMA capacitors, Panasonic FK, C0G and high quality components.
I don’t really care about the DAC on this occasion, but I do care about the great sound that the fifth generation of this series of Aune tube devices delivers.
Via USB, the Aune Flamingo is compatible with a PC, a PAD, a smartphone or a DAP via OTG. Via coaxial, it is compatible with a CD transport, streamer, DAP or other devices with this type of output.
As output, the Flamingo can be connected to headphones via its 6.35mm SE output, to active speakers or to devices with RCA audio input.
The Bluetooth edition allows the Flamingo to be used as a receiver, supporting aptX HD or LDAC.
Operation is extremely simple. The multi-function potentiometer allows you to increase/decrease the volume. One press selects the input, two presses to change the output from OPA to TUBE, one long press to enter the menu to choose from up to 7 filters. Everything is easier with the remote control, although it doesn’t have a long range, just enough for the desktop.
You can switch from tube output to OpAmp output without having to stop the music and without cuts. It’s great to be able to see the differences in sound.
It is clear that at high volumes the device gets quite hot, the vacuum valve can burn.
One aspect that has struck me about the Flamingo is the low voltage at relatively high volume. From 80 to 99 there is a 2.6V difference. That is a lot. The voltage increases in the last few volume steps are very high, almost 2V in the last 9 steps. There is a lot of sensitivity below 60, although there is hardly any voltage. From then on the jumps are big, especially from 80 onwards.
PURE TONE TUBE OUTPUT 1kHz
VOL 90: 1.05V
VOL 91: 1.17V
VOL 92: 1.31V
VOL 93: 1.47V
VOL 94: 1.68V
VOL 95: 1.85V
VOL 96: 2.06V
VOL 97: 2.31V
VOL 98: 2.63V
VOL 99: 2.95V
The output at maximum volume using operational amplifier is a little higher:
OPA VOL 99: 3.12V.
Using the TUBE output, maximum volume can be reached without visible distortion. The result of 2.74V and 180mA is a power of 0.5W. Exceptional. The OPA output «only» reaches VOL 98, without visible distortion, giving 2.63V @1kHz.
Using the TUBE output the maximum volume can be reached without visible distortion. 2.85V and 250mW. Very good.
By OPA at VOL 99, the result is 3.15V @1kHz.
Using the TUBE output the maximum volume can be reached without visible distortion. 2.87V and 82mW. Not bad at all
By OPA at VOL 99, the result is 3.13V @1kHz.
The frequency response in TUBE mode is 20Hz – 20kHz (±0.6dB), which is true in the low range, being, according to my measurements, higher in the high range, being a little more than 1dB at 20kHz. But, of course, my measuring instruments are quite rudimentary.
From the OPA output you can see that there is no drop in the low area, but there is in the high area. To be exact, the same.
The difference between channels is minimal.
You can see that the system is Hi-Res because its bandwidth is from 5Hz to 40kHz.
The output impedance for TUBE is 1.15Ω, while for OPA it is clearly less than 1. Quite good.
Honestly, I have never tried a tube headphone amplifier before. Everyone will have read about, even tasted for themselves, the distinctive flavour that such amplification offers. But I had actually expected that taste to be more intense, even more recognisable. My surprise was also that the difference between selecting the TUBE output and the OPA output is not that different either. The first thing you can distinguish is that the OPA output is slightly louder and that at the sub-bass end there is no such loss. We are talking about -0.6dB at 20Hz and -0.3dB at 30Hz, which is not much, really. If you think that switching from one mode to the other will result in a considerable bass boost, you can forget about it. The jump in volume can almost be more important than that difference, when switching from TUBE to OPA, while playing a bass-heavy track.
There are also differences in the treble between the two outputs, although the FR is the same between the two, only with this increase in volume. The extra sweetness and smoothness in the reproduction of the TUBE output is clearly perceived in the high notes, which are more rounded and less sharp. From the OPA output there is a superior sparkle, a finer and crisper treble, which reaches a higher point. There is a slightly superior analytical and descriptive ability with OPA, a sharper definition and resolution. But I don’t miss anything on TUBE either. In fact, 90% of my use of the Flamingo has been on TUBE, so why have a tube DAC/AMP and not use it?
The low end of the Aune Flamingo only loses a slight rumble in the sub-bass compared to OPA. With TUBE, the bass response is softer and more cushioned, replacing the roughness of OPA with a softer, more elastic surface. This reinforcement of rubberiness by TUBE is appreciated in headphones that are fast and more analytical, achieving a more pleasant and musical response. Although, it is true that the OPA output seems more dynamic, agile and fresh, as well as with more resolution and faster transitions. Bass lines are denser per TUBE and the layering is not as noticeable.
The TUBE media offer a more harmonious and musical presentation. Actually, the Flamingo’s ability to sound very appealing, almost charming, very addictive, lies in the execution of the midrange. First, no one should associate the sound of this valve with a sound that is completely warm, dark or lacking in detail. In no way is that the case. It is analogue, yes, but as is my Burson Audio Playmate with OpAmps V6. Even when doing A/B tests between the two, matching volumes and using a quick switch, it’s surprising to see how the audio quality is almost the same, and they even have almost the same profile. It is clear that the resemblance between the two is superior for OPA. And although this tube is capable of delivering a good amount of current, the Burson Audio Playmate with OpAmps V6, at high gain, has a higher power reserve. It is not for nothing that this is a more powerful amplifier. And that’s when my surprise is even greater, we are talking about a price that is more than double between the two devices and the difference is only in the power.
On the other hand, if you want to gain a little more dynamics, a little more clarity and speed, just switch to OPA, to gain agility in transitions, a little more separation and a more explicit definition. This is noticeable in all ranges, especially in the midrange and treble.
The denser sound in the mids through TUBE and also more cushioned, offers a more homogeneous atmosphere, while the OPA scene is more excited and expansive. The notes tend to rise and escape more through that outlet, while on TUBE everything remains more harmonious and liquid. There is more separation, neatness, definition and resolution through OPA. The slight sensation of a more extended bass towards the LFOs gives you a subtle point of depth that is more elevated than on TUBE, where everything sounds more inoffensive, smooth and rounded.
The Aune Flamingo refers to its sound from both outputs as pure (OPA) and warm (TUBE). I would add that both outputs are very analogue. The op-amps offer a defined sound, with a good level of resolution, cleaner, separate and vivid. While the tube stage adds a component of smoothness, musicality and superior harmonics, which makes this attractive device a very good value for those who want to get into the tube sound, without having to spend a lot of money or even give up the best of a DAC/AMP with operational amplifiers. The ability to instantly switch between TUBE and OPA, while playing music, is totally enviable. As well as being able to enjoy 300mW at 33Ω and 0.5W at 15Ω, which is a power that destroys any dongle, even many portable DAC/AMP for low impedances. Add to this the fact that it is a small powered device, intended for stationary use, but compact and light enough to be transportable, and the result couldn’t be better. But, in my opinion, it is the most attractive device I have on my desk, as well as being minimalist and practical. It is definitely my first choice when it comes to listening to music. Possibly because of the enormous appeal of the soft, warm light of its visible valve, the great, simple and elegant design with its rounded sides and the very effective OLED display. Not forgetting, of course, the remote control and the possibility of being used as a Bluetooth receiver. Without a doubt, this is the most distinctive DAC/AMP with the most personality and the best sound you can buy for just over $200.
Earphones Used During Analysis
- NiceHCK F1.
- BQEYZ Winter.
- Dunu Kima.
- KiiBOOM Allure.
- Letshuoer S12 Pro.
- TinHiFi P1 MAX Giant Panda.
- Rose QT9 MK2s.
- Yanyin Aladdin.
- ISN H40.
- TinHiFi T4 Plus