This is a review and detailed measurements of the Aune X1s GT stereo DAC and balanced headphone amplifier. It was stent to me by the company and costs US $320.
I really like the industrial design of the X1s GT:
It looks even better than the picture in a dark setting with the red accepts nicely illuminating (you can turn off the one around the volume control). As you see you have both unbalanced 1/4 inch headphone output and 4.4 mm pentacon. To select inputs, you simply push the input button. To change filters, double click it and wait for the blue led to change positions.
Power is provided using an external switching power supply:
Unusual for the class is the inclusion of clock reference so you could synchronize it with others in a studio using a master clock (otherwise I have not seen a benefit to it).
While the headphone output is balanced, pre-amp/fixed outputs are only unbalanced RCA.
Aune X1s GT DAC Measurements
Let's start with the DAC dashboard:
Distortion is well below audibility at less than -120 dB. Add some noise to it and it droops to 114 dB in the form of SINAD:
As you see, it lands in the "excellent" category but not in the same class as our state of the art desktop products. This is also reflected in dynamic range:
Intermodulation test unfortunately shows our old "friend," the ESS DAC's class rise in distortion in mid levels:
It is a shame that ESS is still sitting idle after nearly 3 years when we first discovered this issue and not helping all of their designers mitigate this problem.
Jitter test shows some unwanted but harmless products:
There are four filters that are provided:
I wish there was one that was sharper. Its absence causes THD+N versus frequency to get polluted with out of band spectra:
Linearity is excellent showing high accuracy:
Finally, multitone output is excellent due to low distortion of the device:
Aune X1s GT Headphone Amplifier Measurements
Let's start with our noise level at 50 mv output:
This is above average but again, not at the top of the class as I like to see:
The inclusion of balanced output allows us to get healthy levels of power:
Note that lowering the volume control helps with the noise level. It seems that unlike what 99% of the companies do, the volume control is acting on the headphone amplifier and not the gain of the DAC.
Switching to unbalanced output we naturally get less power but still good:
Channel matching is decent:
Finally, varying the load while sweeping for distortion we get:
Good news is that even at max volume there is no clipping down to about 50 ohm load. This means that if you hear distortion, it is in your source.
On the other hand, there is a slight drop in output as the load goes down. I measured the output impedance and it is 5 ohm in unbalanced and likely 10 ohm in balanced. This is borderline too high. On the plus side it means that its output will be more robust against damage due to shorts and such.
Headphone Listening Tests
I tested unbalanced output using my Sennheiser HD650. There was just enough volume there to be loud enough and produce excellent fidelity. If you want to have some headroom, you would want to swap its default cord for balanced. Speaking of that, I tested the balanced output with my Drop Ether CX. There was excellent performance to be had there until you pushed it to max volume. There, it would get a tiny bit distorted but then was too loud to listen to on a normal basis.
Conclusions
Competition is so tough when it comes to desktop DAC and amplifiers. Aune struggles to get into that high end category but produces enough good numbers that when combined with its excellent looks, gets a positive reaction from me. I hope there is an "X2" version which pushes the performance one step higher.
Per above, I am going to recommend the Aune X1s GT.
------------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
I really like the industrial design of the X1s GT:
It looks even better than the picture in a dark setting with the red accepts nicely illuminating (you can turn off the one around the volume control). As you see you have both unbalanced 1/4 inch headphone output and 4.4 mm pentacon. To select inputs, you simply push the input button. To change filters, double click it and wait for the blue led to change positions.
Power is provided using an external switching power supply:
Unusual for the class is the inclusion of clock reference so you could synchronize it with others in a studio using a master clock (otherwise I have not seen a benefit to it).
While the headphone output is balanced, pre-amp/fixed outputs are only unbalanced RCA.
Aune X1s GT DAC Measurements
Let's start with the DAC dashboard:
Distortion is well below audibility at less than -120 dB. Add some noise to it and it droops to 114 dB in the form of SINAD:
As you see, it lands in the "excellent" category but not in the same class as our state of the art desktop products. This is also reflected in dynamic range:
Intermodulation test unfortunately shows our old "friend," the ESS DAC's class rise in distortion in mid levels:
It is a shame that ESS is still sitting idle after nearly 3 years when we first discovered this issue and not helping all of their designers mitigate this problem.
Jitter test shows some unwanted but harmless products:
There are four filters that are provided:
I wish there was one that was sharper. Its absence causes THD+N versus frequency to get polluted with out of band spectra:
Linearity is excellent showing high accuracy:
Finally, multitone output is excellent due to low distortion of the device:
Aune X1s GT Headphone Amplifier Measurements
Let's start with our noise level at 50 mv output:
This is above average but again, not at the top of the class as I like to see:
The inclusion of balanced output allows us to get healthy levels of power:
Note that lowering the volume control helps with the noise level. It seems that unlike what 99% of the companies do, the volume control is acting on the headphone amplifier and not the gain of the DAC.
Switching to unbalanced output we naturally get less power but still good:
Channel matching is decent:
Finally, varying the load while sweeping for distortion we get:
Good news is that even at max volume there is no clipping down to about 50 ohm load. This means that if you hear distortion, it is in your source.
On the other hand, there is a slight drop in output as the load goes down. I measured the output impedance and it is 5 ohm in unbalanced and likely 10 ohm in balanced. This is borderline too high. On the plus side it means that its output will be more robust against damage due to shorts and such.
Headphone Listening Tests
I tested unbalanced output using my Sennheiser HD650. There was just enough volume there to be loud enough and produce excellent fidelity. If you want to have some headroom, you would want to swap its default cord for balanced. Speaking of that, I tested the balanced output with my Drop Ether CX. There was excellent performance to be had there until you pushed it to max volume. There, it would get a tiny bit distorted but then was too loud to listen to on a normal basis.
Conclusions
Competition is so tough when it comes to desktop DAC and amplifiers. Aune struggles to get into that high end category but produces enough good numbers that when combined with its excellent looks, gets a positive reaction from me. I hope there is an "X2" version which pushes the performance one step higher.
Per above, I am going to recommend the Aune X1s GT.
------------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
