This is a review and detailed measurements of Yulong DA10 balanced DAC and headphone amplifier. It was kindly sent to me by Shenzhen Audio for testing. It costs USD $1,200 but is currently on sale for $1,150. Needless to say, my expectations are high at this price range.
The industrial design is unremarkable, sans a large, rather high resolution display:
The display seems to be designed for audio nerds in the way it highlights the sampling rate of music being played in large, center part of the display
, leaving the volume indicator to tiny font on bottom right. From usability point of view, I like to see the volume level in the middle and sample rate at the bottom.
What is nice is seeing everything at once from filter settings to different modes. A click of the volume control lets you cycle through them and by rotating, you can change them. As such, there are no submenus to get lost in.
As is evident, we have both 1/4 inch headphone jack and XLR for "balanced" connection. The volume control is a rotary encoder that works linearly.
The back panel has the usual connections you expect to see:
Of note, I was pleased to see both FCC and CE safety and regulatory compliance. WIth mains input on a device, I always like to see these markings as there are high voltages running around a metal enclosure.
I let you go through the page for it on Shenzhen Audio website for additional detail.
DAC Measurements
I started testing by putting the DA10 into DAC mode and leaving everything else as set by the manufacturer. This is our dashboard view for XLR output, USB input:
The output was a bit "hot" at 4.2 volt but close enough to the 4.0 volt nominal value I like to see. Reducing the volume to get it down to 4 volts did not improve performance. On that front, the measurements are right on the money with respect to what is published. That places the SINAD (signal over noise and distortion) at 112 which firmly plants the DA10 in our top tier of DACs tested:
At this price, I would have liked to see the SINAD in the 115 dB though.
Dynamic range seems to fall short of specifications by a good bit and is likely responsible for above shortfall:
Jitter is not visible due to a) good design and b) noise floor that is a few dB high and hence hides small components:
Linearity graphically looks perfect but there was a bit of noise at the extreme bottom, slowing down the measurements a bit:
AKM DAC chip is used so we don't have to worry about "ESS IMD Hump:"
Noise level though in both balanced and RCA outs is above our reference Topping DX3 Pro which retails for less than a fourth of D10's price.
We see random spikes crowding the valley between our 32 tones in multitone testing:
THD+N versus frequency shows some oddities:
Seems like different noise/distortion mechanisms become dominant at different levels. Good news though is that at highest frequencies, it is well managed.
Frequency response is ruler flat as it should be:
Headphone Amplifier Measurements
I ran my new signal to noise ratio measurement at just 50 millivolt output to test how noisy the device might be with sensitive IEMs and this is what I get:
We still don't have a lot of data to draw a big conclusion but having it land at the top of the scale is good.
I almost didn't run channel balance test, thinking that it is digitally controlled so should be perfect but was not:
The level of drift is small even at the limit but I did not expect to see much deviation until the end.
Output impedance from the 1/4 inch jack is excellent:
The most important test for headphone amplifiers is the power versus THD+N as that almost immediately tells us the subjective performance of the device. Let's start with our 300 ohm load:
My minimum standard is 100 milliwatts and the D10 gets there. At this price range though, I like to see more power. Once again we see higher noise floor than reference Topping DX3 Pro for example.
Switching to the other extreme at 33 ohm, emphasizing current delivery we get much better performance:
At 1 watt of output, I expect the subjective experience to be excellent.
Testing at 50 ohm in both regular and "balanced" headphone connections, we see the quadrupling of the power in teh latter case as expected:
In balanced mode then, the D10 should be able to drive anything.
Listening Tests
As always I start testing with my Sennheiser HD-650 headphones to see how well the amplifier performs with high impedance headphones. Here, the experience was satisfactory but not overwhelming. I could not for example get the drivers to produce any physical sensation of bass. With higher powered amplifiers, I can get my ear lobes vibrating. Balanced mode which I did not test should be able to remedy this.
Switching to Hifiman HE-400i was much nicer. The D10 drove them to thundering dynamics with no difficulty. Fidelity was excellent all around.
Conclusions
We are spoiled at ASR with discovery of good number of high-performing dacs and headphone amplifiers. Given the cost of Yulong D10, I expected it to match or beat those reference devices. That did not happen. A persistent high noise floor (measured, but likely not audible) persisted throughout the measurements. Power output with 1/4 inch jack at 300 ohm was also a bit disappointing.
On the positive front, if you use balanced output, you should be able to drive any headphone to very high levels of fidelity. Most of our reference level DACs lack headphone amplifiers and that is integrated here in the D10. In addition, it is good to see regulatory certifications on the D10.
Overall, the Yulong D10 leaves me just a bit cold so I can't fully recommend it. It is up to you to decide if its feature set, availability, etc. makes it better than other recommended products.
------------
As always, questions, comments, recommendations, etc. are welcome.
I had trouble getting my tractor running yesterday due to battery finally dying. Need money for a new one. Please donate using:
Patreon: https://www.patreon.com/audiosciencereview), or
upgrading your membership here though Paypal (https://audiosciencereview.com/foru...eview-and-measurements.2164/page-3#post-59054).
The industrial design is unremarkable, sans a large, rather high resolution display:
The display seems to be designed for audio nerds in the way it highlights the sampling rate of music being played in large, center part of the display
, leaving the volume indicator to tiny font on bottom right. From usability point of view, I like to see the volume level in the middle and sample rate at the bottom. What is nice is seeing everything at once from filter settings to different modes. A click of the volume control lets you cycle through them and by rotating, you can change them. As such, there are no submenus to get lost in.
As is evident, we have both 1/4 inch headphone jack and XLR for "balanced" connection. The volume control is a rotary encoder that works linearly.
The back panel has the usual connections you expect to see:
Of note, I was pleased to see both FCC and CE safety and regulatory compliance. WIth mains input on a device, I always like to see these markings as there are high voltages running around a metal enclosure.
I let you go through the page for it on Shenzhen Audio website for additional detail.
DAC Measurements
I started testing by putting the DA10 into DAC mode and leaving everything else as set by the manufacturer. This is our dashboard view for XLR output, USB input:
The output was a bit "hot" at 4.2 volt but close enough to the 4.0 volt nominal value I like to see. Reducing the volume to get it down to 4 volts did not improve performance. On that front, the measurements are right on the money with respect to what is published. That places the SINAD (signal over noise and distortion) at 112 which firmly plants the DA10 in our top tier of DACs tested:
At this price, I would have liked to see the SINAD in the 115 dB though.
Dynamic range seems to fall short of specifications by a good bit and is likely responsible for above shortfall:
Jitter is not visible due to a) good design and b) noise floor that is a few dB high and hence hides small components:
Linearity graphically looks perfect but there was a bit of noise at the extreme bottom, slowing down the measurements a bit:
AKM DAC chip is used so we don't have to worry about "ESS IMD Hump:"
Noise level though in both balanced and RCA outs is above our reference Topping DX3 Pro which retails for less than a fourth of D10's price.
We see random spikes crowding the valley between our 32 tones in multitone testing:
THD+N versus frequency shows some oddities:
Seems like different noise/distortion mechanisms become dominant at different levels. Good news though is that at highest frequencies, it is well managed.
Frequency response is ruler flat as it should be:
Headphone Amplifier Measurements
I ran my new signal to noise ratio measurement at just 50 millivolt output to test how noisy the device might be with sensitive IEMs and this is what I get:
We still don't have a lot of data to draw a big conclusion but having it land at the top of the scale is good.
I almost didn't run channel balance test, thinking that it is digitally controlled so should be perfect but was not:
The level of drift is small even at the limit but I did not expect to see much deviation until the end.
Output impedance from the 1/4 inch jack is excellent:
The most important test for headphone amplifiers is the power versus THD+N as that almost immediately tells us the subjective performance of the device. Let's start with our 300 ohm load:
My minimum standard is 100 milliwatts and the D10 gets there. At this price range though, I like to see more power. Once again we see higher noise floor than reference Topping DX3 Pro for example.
Switching to the other extreme at 33 ohm, emphasizing current delivery we get much better performance:
At 1 watt of output, I expect the subjective experience to be excellent.
Testing at 50 ohm in both regular and "balanced" headphone connections, we see the quadrupling of the power in teh latter case as expected:
In balanced mode then, the D10 should be able to drive anything.
Listening Tests
As always I start testing with my Sennheiser HD-650 headphones to see how well the amplifier performs with high impedance headphones. Here, the experience was satisfactory but not overwhelming. I could not for example get the drivers to produce any physical sensation of bass. With higher powered amplifiers, I can get my ear lobes vibrating.
Balanced mode which I did not test should be able to remedy this.Switching to Hifiman HE-400i was much nicer. The D10 drove them to thundering dynamics with no difficulty. Fidelity was excellent all around.
Conclusions
We are spoiled at ASR with discovery of good number of high-performing dacs and headphone amplifiers. Given the cost of Yulong D10, I expected it to match or beat those reference devices. That did not happen. A persistent high noise floor (measured, but likely not audible) persisted throughout the measurements. Power output with 1/4 inch jack at 300 ohm was also a bit disappointing.
On the positive front, if you use balanced output, you should be able to drive any headphone to very high levels of fidelity. Most of our reference level DACs lack headphone amplifiers and that is integrated here in the D10. In addition, it is good to see regulatory certifications on the D10.
Overall, the Yulong D10 leaves me just a bit cold so I can't fully recommend it. It is up to you to decide if its feature set, availability, etc. makes it better than other recommended products.
------------
As always, questions, comments, recommendations, etc. are welcome.
I had trouble getting my tractor running yesterday due to battery finally dying. Need money for a new one. Please donate using:
Patreon: https://www.patreon.com/audiosciencereview), or
upgrading your membership here though Paypal (https://audiosciencereview.com/foru...eview-and-measurements.2164/page-3#post-59054).
