This is a review and detailed measurements of the ddHiFi TC44B balanced portable DAC and headphone amplifier. It was kindly sent to me by a member and costs US $90 although I think Drop carried it for $80.
The TC44B brings a bit of departure in form factor in its triangular shape:
A permanent USB-C cable comes with it. As you can see, there are only provisions of "balanced" headphones in the form of 2.5 and 4.4 mm jack. Please do NOT attempt to convert this to 3.5 mm unbalanced as that can damage the unit. You have to have balanced wiring for your headphone to use this adapter.
ddHiFi TC44B Measurements
As usual we start with our dashboard of 1 kHz tone:
This is excellent performance, landing the TC44B near top of the class:
There are countless DACs including some costing thousands of dollars which can't attain this level of performance!
Unfortunately the output level is only 2 volts. This will hurt the performance of TC44B on high impedance headphones as we will shortly see.
Dynamic range is excellent which should yield very low noise floor for sensitive IEMs:
Jitter test is a weak point for many portable dongles but not this device:
Multitone shows the same low distortion results:
Like most dongles, the way the TC44B advertises itself to Windows causes my ASIO interface emulation to get confused and produce higher noise and distortion. In the above tests, I did not use that scheme and instead just played the test tones using my Roon player. For sweep tests however, I have to use the ASIO layer so don't go by the noise floor and just pay attention to the maximum power:
With balanced dongles we are able to get 4 volts typically. But since the TC44B only outputs 2 volts, it suffers here relative to the top ranked devices. At the same time, it is miles ahead of those that only output 1 volt.
Current delivery is very good though so with 32 ohm load, we get top class performance:
Company spec is 120 milliwatts which is what we measured.
TC44B Headphone Listening Tests
Performance with my Drop Ether CX headphone which is 25 ohm was excellent. I could get plenty of volume and satisfying experience. I swapped the cables on my Sennheiser HD-650 to balanced and there, with content that was mixed loud, there was plenty of volume and excellent performance. With content that was less so, it was still loud but borderline.
Conclusions
The TC44B nails objective performance, producing desktop class performance in a tiny package. Its output though is half as much as the other balanced dongles we have tested so can't drive high impedance headphones as loud. With low impedance, it is there with distortion and noise-free performance.
I am happy to put the ddHifi TC44B on my recommended list. It is very well executed DAC and headphone amplifier.
------------
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/
The TC44B brings a bit of departure in form factor in its triangular shape:
A permanent USB-C cable comes with it. As you can see, there are only provisions of "balanced" headphones in the form of 2.5 and 4.4 mm jack. Please do NOT attempt to convert this to 3.5 mm unbalanced as that can damage the unit. You have to have balanced wiring for your headphone to use this adapter.
ddHiFi TC44B Measurements
As usual we start with our dashboard of 1 kHz tone:
This is excellent performance, landing the TC44B near top of the class:
There are countless DACs including some costing thousands of dollars which can't attain this level of performance!
Unfortunately the output level is only 2 volts. This will hurt the performance of TC44B on high impedance headphones as we will shortly see.
Dynamic range is excellent which should yield very low noise floor for sensitive IEMs:
Jitter test is a weak point for many portable dongles but not this device:
Multitone shows the same low distortion results:
Like most dongles, the way the TC44B advertises itself to Windows causes my ASIO interface emulation to get confused and produce higher noise and distortion. In the above tests, I did not use that scheme and instead just played the test tones using my Roon player. For sweep tests however, I have to use the ASIO layer so don't go by the noise floor and just pay attention to the maximum power:
With balanced dongles we are able to get 4 volts typically. But since the TC44B only outputs 2 volts, it suffers here relative to the top ranked devices. At the same time, it is miles ahead of those that only output 1 volt.
Current delivery is very good though so with 32 ohm load, we get top class performance:
Company spec is 120 milliwatts which is what we measured.
TC44B Headphone Listening Tests
Performance with my Drop Ether CX headphone which is 25 ohm was excellent. I could get plenty of volume and satisfying experience. I swapped the cables on my Sennheiser HD-650 to balanced and there, with content that was mixed loud, there was plenty of volume and excellent performance. With content that was less so, it was still loud but borderline.
Conclusions
The TC44B nails objective performance, producing desktop class performance in a tiny package. Its output though is half as much as the other balanced dongles we have tested so can't drive high impedance headphones as loud. With low impedance, it is there with distortion and noise-free performance.
I am happy to put the ddHifi TC44B on my recommended list. It is very well executed DAC and headphone amplifier.
------------
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/
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