This is a review and detailed measurements of the Yulong Aquila II USB DAC and headphone amplifier. It was kindly purchased by a member and drop shipped to me for testing. It costs US $640.
The Auila II breaks the mold of rectangular boxes for desktop DACs with compound angles:
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The volume control also navigates the menus by first pushing it in multiple times until you land on the on screen item to modify and then turning the dial. The display is IPS and has very fine resolution which I appreciated.
The back panel has the usual connectivity:
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The unit was plug and play with Windows over USB connection. Operationally it ran somewhat warm but no worse than other high performance DAC and amps.
Balanced DAC Audio Measurements
For the DAC portion I focused on performance of the XLR output only. Here is our dashboard:
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Two years ago I would jump with joy at such low distortion and noise rating as reflected by the SINAD. But today, SINAD of 111 dB is not very competitive:
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Noise by itself seems to be a bit of an issue:
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This reflects just the same in IMD distortion versus level:
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The DX3 Pro (dashed blue) is one third the price so having more noise than it is not very good.
There is some jitter that is caused by power supply noise:
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Not remotely an audible issue though.
An option people wondering about has been the ASRC mode being on and off. This is exposed in Auila but as you see, it made no difference with USB as the source.
Linearity was very good:
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There are only three filters exposed:
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I used the sharp one for the following test:
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Company measurements are a few dBs better than what I am getting (0.0002% versus 0.0006%). I don't know what explains the discrepancy.
Finally here is our multitone:
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Headphone Amplifier Measurements
Good bit of power is provided especially in balanced mode:
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Alas, once again noise is higher than it should be. The volume control is analog though (but digitally controlled) so perhaps at lower settings it would show less noise.
Here is unbalanced performance into 33 ohm:
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I did not have time to listen to it but I suspect it will sound good given the ample amount of power as long as you don't use an overly sensitive headphone/IEM.
Conclusions
Expectations is everything and at this price, I expect "instrument grade" measurement results and sadly we don't get it. Subjectively it will sound fine with its powerful headphone amp. So if you like its looks, it would make an OK purchase. It doesn't meet the bar for me though from engineering point of view so I can't recommend it.
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As always, questions, comments, recommendations, etc. are welcome.
Have to help my wife can more tomatoes but took a break to do this review. Shows you how much I value the money you all put in my pocket! So
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