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SMSL D400 Pro Balanced DAC Review

Rate this DAC:

  • 1. Poor (headless panther)

    Votes: 8 3.2%
  • 2. Not terrible (postman panther)

    Votes: 25 9.9%
  • 3. Fine (happy panther)

    Votes: 126 49.8%
  • 4. Great (golfing panther)

    Votes: 94 37.2%

  • Total voters
    253

amirm

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This is a review and detailed measurements of the SMSL D400 Pro balanced stereo DAC with Bluetooth support. It was sent to me by the company and costs US $619.
SMSL D400 Pro Balanced Stereo DAC Review.jpg

The scalloped front together with the high resolution and bright display make this one of the most beautiful products SMSL has released. The processor behind the display is very speedy as well. I like that the volume level is now in big letters and sample rate is small. You have the usual connections in the back:
SMSL D400 Pro Balanced Stereo DAC Bluetooth Back Panel Rear Review.jpg


SMSL D400 Pro DAC Measurements
As usual we start with our dashboard using balanced XLR Out with volume set to 0:
SMSL D400 Pro Balanced Stereo DAC Measurement.png

We expect top performance from SMSL and we get that here, landing the D400 Pro in our top 20 list of best DACs tested:
best balanced DAC stereo review.png

Note that company dashboard is at 5 volts output and I suspect with a-weighting and hence the reason its higher rating. RCA has the usual hit in SNR but still superb:
SMSL D400 Pro Balanced Stereo DAC RCA Measurement.png


As noted, you have more output than 4 volts and performance keeps getting better as a result of it:
SMSL D400 Pro Balanced Stereo DAC THD vs level Measurement.png


Dynamic range is superb:
SMSL D400 Pro Balanced Stereo DACDNR  Measurement.png


Linearity is perfect:
SMSL D400 Pro Balanced Stereo DAC Linearity Measurement.png


I expected better performance in multitone for this class of DAC:
SMSL D400 Pro Balanced Stereo DAC Multitone Measurement.png


Similarly, there are some jitter/spurious tones in Jitter test which while inaudible, shouldn't be there:
SMSL D400 Pro Balanced Stereo DAC Jitter Measurement.png


50 Hz performance is excellent but again, it should be a few dBs better:
SMSL D400 Pro Balanced Stereo DAC 50 Hz FFT Measurement.png


Can't complain about IMD performance though:
SMSL D400 Pro Balanced Stereo DAC IMD Measurement.png


We have the usual set of filters:
SMSL D400 Pro Balanced Stereo DAC Filter Measurement.png

SMSL D400 Pro Balanced Stereo DAC Frequency response Measurement.png


Despite the excellent attenuation of the filter, THD+N vs frequency is not as good as I like to see in this class:
SMSL D400 Pro Balanced Stereo DAC THD vs frequency Measurement.png


Conclusions
The D400 Pro sports a new and attractive look for SMSL's high-end products. On performance front, we start very well with SINAD and DNR essentially at state of the art level. In some other tests though, we lose a bit of that which would be forgivable in lower cost products but given the positioning, it should have been ironed out. Mind you, they are not audible issues but you know, in this price range we like to see perfection. Net, net, you get better looks and give up a bit of objective performance.

I am going to recommend the SMSL D400 Pro as it provides excellent performance.

Technical Details/Specifications:

Inputs - USB, coaxial, optical, I2S, Bluetooth, AES
Outputs - RCA, XLR
Output level - XLR: 5Vrms | RCA: 2.5Vrms
Output impedance - XLR: 200Ω | RCA: 100Ω
THD+N - XLR: 0.00006% | RCA: 0.00008%
Dynamic range - XLR: 132dB | RCA: 126dB
SNR - XLR: 132dB | RCA: 126dB
USB transmission - Asynchronization
USB compatibility - Windows 7/8/8.1/10/11 (needs driver), Mac OSX 10.6 or later, Linux
MQA decoder - USB, optical, coaxial

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SMSL has 28 DACs listed in their website as of today. It can be 30 by the time you check it out. They should measure them all, send Amir their measurement data for validation and we should close the topic of SMSL DAC until 2024Q4 in my opinion.
 
Good performance, but, considering the price, it would IMHO be nice to have a headphone amp included.
Interesting design BTW, I've seen similar on some hi-end(ish) amp, can't recall the manufacturer.

Sidenote: So, it seems, MQA is not quite dead yet?
 
This is a review and detailed measurements of the SMSL D400 Pro balanced stereo DAC with Bluetooth support. It was sent to me by the company and costs US $619.


Conclusions
The D400 Pro sports a new and attractive look for SMSL's high-end products.Net, net, you get better looks and give up a bit of objective performance.
You forgot a 4 there, it's the D400 not D00 ;)

Aesthetics... it's very personal.
You like it, I think the new look is hideous and just because of that an instant no buy for me.

Also those little quirks should not be there in a product that costs over 600 dollars.
 
Despite the excellent attenuation of the filter, THD+N vs frequency is not as good as I like to see in this class:
SMSL D400 Pro Balanced Stereo DAC THD vs frequency Measurement.png
It's flat and smooth and it doesn't get any better than this, so what's the problem?
 
SMSL has 28 DACs listed in their website as of today. It can be 30 by the time you check it out. They should measure them all, send Amir their measurement data for validation and we should close the topic of SMSL DAC until 2024Q4 in my opinion.
There are so many perfect or near perfect DACs to choose especially from SMSL, Topping or other manufacturers but still a lot of interesting loudspeakers to discover. So ...;)
 
It's flat and smooth and it doesn't get any better than this, so what's the problem?
The line should be lower.
 
Probably the comparison with other SMSL DACs:

View attachment 322909

It's really strange though,the wide bandwidth gives a really strong hit here in D400.

Thanks Amir!
This one is worse, not better, because it has more curvature vs frequency... which is what it is all about in any "X vs. frequency" test.
 
There are so many perfect or near perfect DACs to choose especially from SMSL, Topping or other manufacturers but still a lot of interesting loudspeakers to discover. So ...;)
Speaker "lab" is competing for floor space with the last of the garden harvest! :) That is on top of a speaker I measured recently which has an issue so has to be swapped and retested.
 
It cannot be lower than indicated by the 1kHz THD+N which you commented as "We expect top performance from SMSL and we get that here".
Different tests. The THD+N vs frequency has more than double the bandwidth and this particular DAC (chip) has noise shaping which degrades performance here.
 
This one is worse, not better, because it has more curvature vs frequency... which is what it is all about in any "X vs. frequency" test.
Ok,like this one then:

1698826684444.png

Seems that something is off in D400.

Edit:If noise shaping is involved it makes sense.
 
I am thinking companies should move to next phase. The SOTA war is over for now, if they want to charge premium price then more meaningful features, please! To me the most amazing feature is the in-built PEQ like in RME and Qudelix product. System level EQ not a brighter screen is worth paying hundred $ for
 
Should have had a HQ headphone amp for this price too.. DL200 and DS6s are likely much better for the money
 
And here's me still thinking ten year old thoughts that £/$600 isn't much to pay for a dac..... How times have changed :D

I actually quite like the look of the thing but if SMSL have all those dacs on the market, they really need to weed them down to a smaller number of superbly performant ones in my view as they're spreading themselves very thinly. Maybe they just make a giant batch only of one model and then onto the next?

A hidden-away black box is my level for such a thing now, but if it has to be on show, I do see the point of a nicer case and styling and in the higher end where cosmetics are more important away from this site, this is relative peanuts (double the price or more if a dealer sold it but even then...).
 
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Obviously great performance, but the real reason for the price premium is the gorgeous case. It's a really pretty piece of audiophile jewelry. And this is a final leap for both Topping and SMSL. They are creating not only edge of the art performance products, but giving those products ultra premium casing at what to me seems like super reasonable pricing. I couldn't imagine buying something like this from our legacy audiophile providers for less than $2-3k, and even then, we'd be lucky if the SINAD even hit 95 db. It's really a tremendous value, and offering this level of fit, features, finish and performance at this price is unprecedented.
 
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