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Review and Measurements of SMSL M100 DAC

amirm

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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:"
SMSL M100 USB DAC Audio Review.jpg

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:

SMSL M100 USB DAC Back Panel Audio Review.jpg

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:
SMSL M100 USB DAC Audio Measurements.png


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:

Best Audio DACs Reviewed and Measured 2019.png


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"):

SMSL M100 USB DAC IMD Audio Measurements.png


Using 32 tones instead of just two above, we get:
SMSL M100 USB DAC DNR Audio Measurements.png


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:
SMSL M100 USB DAC Linearity Audio Measurements.png


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:

SMSL M100 USB DAC Jitter Audio Measurements.png


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:

SMSL M100 USB DACDNR Audio Measurements.png


This is the reconstruction filter response:
SMSL M100 USB DAC White noise Audio Measurements.png


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.

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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/
 

daftcombo

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Thanks for the review Amir!

It looks like a cheap alternative to the Topping D10 indeed. Did you test it at 48 kHz like on the picture, with the same results as 44.1 kHz?
 

sajunky

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Thanks for the tests. I also see it as a good alternative to the topping D10. Slow roll-off filter - did they do it to get better piano sound? They listen to sajunky, perhaps. Just wondering. A few dB in already inaudible range do not matter, so I would chose one with better sound.
 

estuardo4

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Amir, thank you for the review.

It seems it's a product very similar to the SMSL Sanskrit 10, but with AKM DAC instead of ESS, no remote and with better measurements. Do you remember that you have to use AUX power for the Sanskrit even if you use the USB connection? It seems that SMSL corrected the issue with the M100.
 
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amirm

amirm

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It seems it's a product very similar to the SMSL Sanskrit 10, but with AKM DAC instead of ESS, no remote and with better measurements. Do you remember that you have to use AUX power for the Sanskrit even if you use the USB connection? It seems that SMSL corrected the issue with the M100.
That's correct. It may also be that this is a lower power device so doesn't max out USB the same way.
 

SIY

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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.

We had the Beyond Hot Italian Sausage last night. I can't say if it tastes like the real thing since I haven't eaten any meat in 55 years or so, but it sure tasted good. Haven't had the Impossible (they're not available for consumer purchase yet), but the Beyond Burger is pretty tasty.

Oh, and nice job, SMSL! Good engineering costs no more than bad engineering, but somehow it doesn't always happen.
 

cshake

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I'm impressed, looks like the D10 has a solid competitor. I'm still going to wait for the V2 of the KTB with the fixed ESS hump since I'm looking for a budget "future-proof" DAC that I can put in a custom low-profile enclosure behind my Atom amp to never look at and forget about (so I don't have to think about audio when I next upgrade the computer), but this has lots of potential. Hope it sells well to encourage more good engineering for good prices going forward.
 

Hugo9000

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Thank you @amirm for the review! I've had my SMSL M100 just over 6 months now, and it has been completely glitch free. I was curious about its measured performance, but I was too lazy to send mine in, so I'm grateful to @lunagreenjp haha!

SMSL's own specs list SNR of 106 dB, and THD+Noise of 0.0005%, so this unit under test was a bit better in SNR, and a bit worse in THD+N. Nice that they publish specs from their own tests and that they don't seem to inflate the numbers! :) And I like that they have representatives that participate here at ASR.

Power consumption is listed by SMSL for this DAC as 1.2 W, while the Sanskrit 10th is listed as 1.5 W, so the M100 is indeed a lower power device. I tried mine at first using a second USB cable to the "aux power" input, but I couldn't detect any difference, so I removed the extra cable after the first few days. So almost 6 months of daily use with no noticeable issues of any kind powered only by the single USB input. I was turning it off when I wasn't at my computer for the first couple of weeks or so, but then I decided to just leave it powered on all the time. Mine is black like the review sample. It has a very nice and solid feel for something so small. My only other external DAC at the moment is the SMSL iDEA, which I bought shortly after Archimago tested and reviewed one, and I've been very happy with that small and inexpensive device as well. My M100 is feeding my JDS Labs Atom, incidentally.

I'm looking forward to your review of the SMSL M500 that @SMSL-Mandy said will be shipping to you from China.

(TL;DR: Thank you for the measurements and review, and here is my anecdotal report of 6 months of no problems with my own M100 haha!)
 
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phpp

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amirm

amirm

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Shadrach

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Thanks for the review amirm.
A decent competently designed product, transparent at 16 bit if unexceptional performance otherwise.
I quite like the look. I hope they sell well.
 

restorer-john

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A strange choice to use a mixture of Torx and Philips screws on the rear panel.
 

E. Damstra

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The M100 is on my computer desk and I am happy with the sound. At first the connection was USB direct to my PC. This brought on severe hiss/distortion. Later I connected the M100 through a TP-Link USB-hub (self powerd hub) and everything went quit and I could enjoy good sound at my desktop.
 

MediumRare

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Given the generally strong performance, the key question is: is any of the difference between a unit like this and one of the top DACs (such as a Benchmark) actually audible? Amir (& others), what do you think about doing a null test and posting the wav files (A, B, Delta) for us to run on our own systems and see if we can resolve the Delta?
 

Tidaliser

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I'm interested in buying one of these DACs but not for desktop use, but for use in a car audio system. I currently have a topping D10 in my car audio setup as the only source of audio, it sounds amazing and does the job of playing Tidal from my Andriod phone, using USB audio player pro of course.

The downside of the D10 though is the single USB port and having to power it directly from my phone, which drains the battery quite a bit, approx 20% per hour, it can't be doing my phone battery much good with daily use.

I haven't found a good solution for powering the D10 off my phone, my phone if it detects power from a OTG Y cable switches to charge mode and won't detect the DAC, what might work is USB cable with 5v totally separated from the phone but that's another story and more pain / fiddle factor.

So the solution is to maybe use a M100 and the AUX power input from a clean 5V supply in my car then the audio data from my phone - using minimal power from my phone.

So my question is - would this work in terms of using the AUX power of the M100 to power it resulting in minimal current drain on the data input from my phone, I know in theory this should work but has anyone tested this with Andriod and using the AUX power input ?

My other question is whether the M100 turns on by default when you apply power ? seeing as the DAC will be out of sight / unreachable.

Also if anyone has a good solution to powering the D10 from an external power supply I'd like to know i.e as per the topping D50 which has a separate 5V input.
 
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