This is a review and detailed measurements of the SMSL M100 DAC. It was kindly sent to me by the member @lunagreenjp who is a distributor for SMSL. The M100 costs US $79.99 on Amazon including prime shipping. As such, it falls into our bargain DAC category.
The one word that describes the look of the M100 is "cute:"
Nice to see a departure from typical desktop form factor without messing it up. The evaluation unit as you see is in black but it also comes with bright blue color.
The power button acts as an input selector if you push it momentarily.
The back panel shows that the M100 is purely USB powered:
If you are using it for USB input, then you just connect the one cable and it provides both data and power. While I did not test it, I assume the Aux input provides power alone for use of the rest of the digital inputs (Toslink optical and coax S/PDIF).
There are no fancy settings in M100 for filters and such. Power it on, select the input and that is that. There is something to be said for the simplicity of its use.
Overall as you can tell, my impression is positive on the M100. The only hitch would be finding a matching headphone amplifier if you were to use one. I don't know if SMSL makes one that looks like the M100.
DAC Audio Measurements
As noted, all of my tests were with USB input so let's see how it looks on our dashboard:
We have nice, nominal 2 volt output that I like to see. Distortion+Noise and hence SINAD (signal over noise and distortion) is fine for a budget DAC, putting it in our tier 2 of all DACs tested regardless of price:
There is a shortfall of 3 dB relative to our favorite budget DAC, the Topping D10.
Intermodulation test is fine given the use of AKM DAC chip (as opposed to ESS which commonly shows the "ESS IMD hump"):
Using 32 tones instead of just two above, we get:
We have a bit more than 16 bits of distortion-free dynamic range. So plenty good for typical 16 bit/CD music playback.
Linearity shows some imperfection as levels approach -120 dB/20 bits:
My jitter test uses the j-test signal which toggles all the bits in the audio samples 250 times a second. A perfect DAC has no dependency on data being fed to it so this square wave and its harmonics are not seen (lost in the noise floor since they are at 24 bits level). The M100 though, shows such a data dependency:
A square wave can be decomposed into an infinite sequence of its primary frequency and odd harmonics. That is what we see above: 250 Hz, then 750 Hz and on and on. Levels are well below audibility at -120 dB so definitely not a concern in practice.
Signal to noise ratio is very good and better than the THD spec:
This is the reconstruction filter response:
This is a typical response for DAC chips int hat instead of rolling off fully at 22.05 kHz, they allow themselves to do so at 24 kHz. It allows a less sharp filter to be used at the expensive of allowing some aliasing components to mirror back into the passband.
Conclusions
The SMSL M100 innovates on the form factor and succeeds in producing a very small and attractive form factor. The cost is very reasonable for what looks to be a competently designed DAC. Compared to Topping D10, you get two other inputs. The D10 however has slightly better measured performance and acts like a USB to Toslink/Coax S/PDIF.
If you don't need any other inputs, my recommendation remains for the Topping D10 due to its larger and more attractive display. Otherwise, the SMSL M100 provides solid competition to it and provides us with more choices in budget DACs.
I am going to put the SMSL M100 on my recommended list.
------------
As always, questions, comments, recommendations, etc. are welcome.
In US, there is a mini craze going on with vegetable based hamburgers that supposedly taste as good as regular beef burger. I tasted the "impossible burger" recently and while it did not meet the stated claim, it wasn't half-bad. I told the story to the panthers and they want to try it. Problem is, it costs even more than beef! So please donate generously so I can give a shot of turning the panthers into vegetarians using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
The one word that describes the look of the M100 is "cute:"
Nice to see a departure from typical desktop form factor without messing it up. The evaluation unit as you see is in black but it also comes with bright blue color.
The power button acts as an input selector if you push it momentarily.
The back panel shows that the M100 is purely USB powered:
If you are using it for USB input, then you just connect the one cable and it provides both data and power. While I did not test it, I assume the Aux input provides power alone for use of the rest of the digital inputs (Toslink optical and coax S/PDIF).
There are no fancy settings in M100 for filters and such. Power it on, select the input and that is that. There is something to be said for the simplicity of its use.
Overall as you can tell, my impression is positive on the M100. The only hitch would be finding a matching headphone amplifier if you were to use one. I don't know if SMSL makes one that looks like the M100.
DAC Audio Measurements
As noted, all of my tests were with USB input so let's see how it looks on our dashboard:
We have nice, nominal 2 volt output that I like to see. Distortion+Noise and hence SINAD (signal over noise and distortion) is fine for a budget DAC, putting it in our tier 2 of all DACs tested regardless of price:
There is a shortfall of 3 dB relative to our favorite budget DAC, the Topping D10.
Intermodulation test is fine given the use of AKM DAC chip (as opposed to ESS which commonly shows the "ESS IMD hump"):
Using 32 tones instead of just two above, we get:
We have a bit more than 16 bits of distortion-free dynamic range. So plenty good for typical 16 bit/CD music playback.
Linearity shows some imperfection as levels approach -120 dB/20 bits:
My jitter test uses the j-test signal which toggles all the bits in the audio samples 250 times a second. A perfect DAC has no dependency on data being fed to it so this square wave and its harmonics are not seen (lost in the noise floor since they are at 24 bits level). The M100 though, shows such a data dependency:
A square wave can be decomposed into an infinite sequence of its primary frequency and odd harmonics. That is what we see above: 250 Hz, then 750 Hz and on and on. Levels are well below audibility at -120 dB so definitely not a concern in practice.
Signal to noise ratio is very good and better than the THD spec:
This is the reconstruction filter response:
This is a typical response for DAC chips int hat instead of rolling off fully at 22.05 kHz, they allow themselves to do so at 24 kHz. It allows a less sharp filter to be used at the expensive of allowing some aliasing components to mirror back into the passband.
Conclusions
The SMSL M100 innovates on the form factor and succeeds in producing a very small and attractive form factor. The cost is very reasonable for what looks to be a competently designed DAC. Compared to Topping D10, you get two other inputs. The D10 however has slightly better measured performance and acts like a USB to Toslink/Coax S/PDIF.
If you don't need any other inputs, my recommendation remains for the Topping D10 due to its larger and more attractive display. Otherwise, the SMSL M100 provides solid competition to it and provides us with more choices in budget DACs.
I am going to put the SMSL M100 on my recommended list.
------------
As always, questions, comments, recommendations, etc. are welcome.
In US, there is a mini craze going on with vegetable based hamburgers that supposedly taste as good as regular beef burger. I tasted the "impossible burger" recently and while it did not meet the stated claim, it wasn't half-bad. I told the story to the panthers and they want to try it. Problem is, it costs even more than beef! So please donate generously so I can give a shot of turning the panthers into vegetarians using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/