This is a review and detailed measurements of the iBasso DC02 USB Phone DAC and headphone amplifier adapter. It is kindly sent to me by a local member. The DC02 is quite expensive for a dongle at US $67.50 with Prime shipping in US. It sports an AKM AK4490 DAC chip that implies great performance and support for high resolution audio.
The DC02 is a bit more beefy than a typical phone headphone adapter:
In person it looks a bit cheaper than the pictures on company website.
In use the dongle gets a bit warmer than ambient temp which is unusual for a dongle.
The DC02 was plug and play on Windows 10 but the ASIO4ALL wrapper (software) that I use to measure it would truncate samples to 16 bits. So for some of the tests I used WASAPI exclusive access on Windows to feed it 24 bit data. That made a tiny bit of improvement so for other tests I used the ASIO interface instead.
USB DAC Dongle Measurements
As usual we start with our dashboard of 1 kHz tone:
The specification says we would only get 0.9 volt output. Here, we are exceeding that by a bit at 0.97 volts. Alas, this is not high enough to drive high impedance headphones as we will see later.
Distortion and noise as summed in SINAD measurement is not bad but not great either:
The $9 Apple dongle does better for example.
Distortion is not an issue as we see in the FFT spectrum with highest spike at -105 dB. It is noise that is the problem and we see that in dynamic range test:
Jitter test shows the myriad of noise sources:
This issue may be system dependent and be worse or better in other setups. A good design however won't have system dependency.
Intermodulation versus level shows the same noise issue:
Most important test is how much power we have for different load impedance of headphones. Let's start with 300 ohm load:
As I suspected in the Dashboard view, there just isn't much power available here at just 3 milliwatts. Sadly the same situation persists at the other spectrum at 33 ohm:
These numbers are very low as compared to other dongles:
Headphone Listening Test
I tested the DC02 with the Sennheiser HD-650 headphones. The results were very disappointing. There was hardly enough volume. No bass response to speak of and the sound was dull overall as a result of it.
Conclusions
The iBasso DC02 seems to have focused on DAC chip rather than headphone amplifier for performance. The DAC chip is not the bottleneck: the low power and high noise level of the headphone amp is. They paid so much extra for the DAC chip and are passing on that cost to customers even though no value is provided there. I hope everyone here knows that it is all about implementation than what components are in an audio device.
Needless to say, I can't recommend the iBasso DC02.
------------
As always, questions, comments, recommendations, etc. are welcome.
Well, for a change, I don't need anything for the panthers as they got a ton of gifts for Christmas. I hope those of you who celebrate had a good time as well. If you feel like donating, here is the link again: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
The DC02 is a bit more beefy than a typical phone headphone adapter:
In person it looks a bit cheaper than the pictures on company website.
In use the dongle gets a bit warmer than ambient temp which is unusual for a dongle.
The DC02 was plug and play on Windows 10 but the ASIO4ALL wrapper (software) that I use to measure it would truncate samples to 16 bits. So for some of the tests I used WASAPI exclusive access on Windows to feed it 24 bit data. That made a tiny bit of improvement so for other tests I used the ASIO interface instead.
USB DAC Dongle Measurements
As usual we start with our dashboard of 1 kHz tone:
The specification says we would only get 0.9 volt output. Here, we are exceeding that by a bit at 0.97 volts. Alas, this is not high enough to drive high impedance headphones as we will see later.
Distortion and noise as summed in SINAD measurement is not bad but not great either:
The $9 Apple dongle does better for example.
Distortion is not an issue as we see in the FFT spectrum with highest spike at -105 dB. It is noise that is the problem and we see that in dynamic range test:
Jitter test shows the myriad of noise sources:
This issue may be system dependent and be worse or better in other setups. A good design however won't have system dependency.
Intermodulation versus level shows the same noise issue:
Most important test is how much power we have for different load impedance of headphones. Let's start with 300 ohm load:
As I suspected in the Dashboard view, there just isn't much power available here at just 3 milliwatts. Sadly the same situation persists at the other spectrum at 33 ohm:
These numbers are very low as compared to other dongles:
Headphone Listening Test
I tested the DC02 with the Sennheiser HD-650 headphones. The results were very disappointing. There was hardly enough volume. No bass response to speak of and the sound was dull overall as a result of it.
Conclusions
The iBasso DC02 seems to have focused on DAC chip rather than headphone amplifier for performance. The DAC chip is not the bottleneck: the low power and high noise level of the headphone amp is. They paid so much extra for the DAC chip and are passing on that cost to customers even though no value is provided there. I hope everyone here knows that it is all about implementation than what components are in an audio device.
Needless to say, I can't recommend the iBasso DC02.
------------
As always, questions, comments, recommendations, etc. are welcome.
Well, for a change, I don't need anything for the panthers as they got a ton of gifts for Christmas. I hope those of you who celebrate had a good time as well. If you feel like donating, here is the link again: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
