This is a review and detailed measurements of the Topping D900 discrete "1-bit" balanced smart DAC with PEQ. It was sent to me by the company and costs US $1,799.
The D900 comes in the most prestigious clothing Topping uses. It gives a feeling of luxury which I like. Touch screen UI is provided for manipulation of setting (as well as a remote which I did not need to use). Back panel shows elimination of RCA output which I am totally fine with:
Instead, we get variable and fixed outputs. Dual optical and coax inputs are provided for those of you with many such inputs. Trigger is now standard seemingly on all Topping products which is much appreciated. It allows one button turn on of your entire system.
As specified, the incoming PCM samples are upsampled to one bit which can then be converted to analog using a simple low pass filter. Parametric EQ completes the picture.
Topping D900 DAC Measurements
The D900 benefited by the tune of 0.5 dB after a few minutes of warm up to produce some of the best noise+distortion numbers I have measured:
The D900 has copious amount of drive, going as high as 12.3 volts!
This allows you to use your power amp at its lowest gain setting, boosting overall system signal to noise ratio. Speaking of that, the dynamic range is excellent:
It goes up about 1 dB at max volume (not shown).
Multitone shows state of the art levels of distortion:
As well as with a 50 Hz signal into 600 ohm load, per stereophile protocol:
Slight error seen at very low amplitude in our IMD sweep:
But then becomes noise dominated and quite low at that.
We see the same small blemish in our linearity test:
The noise floor is extremely low and clean in jitter test:
Which then shows up a couple of inconsequential tones at -140 dB. The spikes on the left are part of the signal and are resolved incredibly well down to 24 bit LSB.
Filter attenuation is excellent:
With the tiniest bit of droop at 20 kHz (0.2 dB):
Wideband noise+distortion shows elevated levels considering what we have measured so far:
But that has an explanation in the form of ultrasonic noise shaping:
So not an audible concern.
Conclusions
As custom DAC implementations go, the D900 is the most perfect I have seen. It represents a heroic effort to near match state of the art, integrated DAC silicon. In other words, you get the buzzword of "discrete 1 bit" DAC with almost no penalty. Getting this level performance out of huge number of individual components is not easy and shows excellent engineering prowess.
Price is up there with respect to IC based solution. But is a "bargain" compared to high-end DACs with similar architecture but usually with worse performance.
I am going to recommend the Topping D900. If you want a custom DAC, this is it.
-----------
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 D900 comes in the most prestigious clothing Topping uses. It gives a feeling of luxury which I like. Touch screen UI is provided for manipulation of setting (as well as a remote which I did not need to use). Back panel shows elimination of RCA output which I am totally fine with:
Instead, we get variable and fixed outputs. Dual optical and coax inputs are provided for those of you with many such inputs. Trigger is now standard seemingly on all Topping products which is much appreciated. It allows one button turn on of your entire system.
As specified, the incoming PCM samples are upsampled to one bit which can then be converted to analog using a simple low pass filter. Parametric EQ completes the picture.
Topping D900 DAC Measurements
The D900 benefited by the tune of 0.5 dB after a few minutes of warm up to produce some of the best noise+distortion numbers I have measured:
The D900 has copious amount of drive, going as high as 12.3 volts!
This allows you to use your power amp at its lowest gain setting, boosting overall system signal to noise ratio. Speaking of that, the dynamic range is excellent:
It goes up about 1 dB at max volume (not shown).
Multitone shows state of the art levels of distortion:
As well as with a 50 Hz signal into 600 ohm load, per stereophile protocol:
Slight error seen at very low amplitude in our IMD sweep:
But then becomes noise dominated and quite low at that.
We see the same small blemish in our linearity test:
The noise floor is extremely low and clean in jitter test:
Which then shows up a couple of inconsequential tones at -140 dB. The spikes on the left are part of the signal and are resolved incredibly well down to 24 bit LSB.
Filter attenuation is excellent:
With the tiniest bit of droop at 20 kHz (0.2 dB):
Wideband noise+distortion shows elevated levels considering what we have measured so far:
But that has an explanation in the form of ultrasonic noise shaping:
So not an audible concern.
Conclusions
As custom DAC implementations go, the D900 is the most perfect I have seen. It represents a heroic effort to near match state of the art, integrated DAC silicon. In other words, you get the buzzword of "discrete 1 bit" DAC with almost no penalty. Getting this level performance out of huge number of individual components is not easy and shows excellent engineering prowess.
Price is up there with respect to IC based solution. But is a "bargain" compared to high-end DACs with similar architecture but usually with worse performance.
I am going to recommend the Topping D900. If you want a custom DAC, this is it.
-----------
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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