• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are daily reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

SMSL D-6s Balanced DAC Review

Rate this DAC:

  • 1. Poor (headless panther)

    Votes: 9 2.5%
  • 2. Not terrible (postman panther)

    Votes: 4 1.1%
  • 3. Fine (happy panther)

    Votes: 24 6.7%
  • 4. Great (golfing panther)

    Votes: 320 89.6%

  • Total voters
    357

dsnyder0cnn

Addicted to Fun and Learning
Joined
Dec 14, 2019
Messages
539
Likes
798
I always like to spend a few weeks listening to a new DAC before taking measurements so that my subjective impressions are not swayed by objective data. After playing with the seven filter settings, I settled on FL3 as sounding the most "right" to my ears. I finally got around to taking some measurements today to see what's what.

TL; DR - avoid filters FL1 and FL6 because of distortion at ~14 kHz and excessive attenuation in the highs. FL3 and FL7 are the most useful. Choose FL3 for most listening, but FL7 may be beneficial with some music, depending on your tastes.


F2 is the default filter. Here's what I see for Amplitude and Impulse response, and Distortion.

1700420222423.png


You'll have to mentally compensate for the inverted horseshoe shared amplitude response. I don't have a great way to compensate for the ADC response of my Focusrite Scarlett 2i2 audio interface, and the vertical scale is only 1 dB, so pretend that this is flat. :)

Impulse response shows extended pre-ringing ripples and exaggerated post-ringing with this filter. No obvious issues with distortion.

With the FL1 and FL6 filters, I'm seeing early attenuation in the high frequencies and a sharp increase in 2nd order distortion at around 14 kHz:

1700420471909.png


I'm not sure how audible this is, but I would avoid FL1 and FL6 for this reason.

After looking at response of all seven filters, FL3 and FL7 are the most useful. FL3 has a little more pre-ringing than I would like, but it's under 5% from -500 to -140 microseconds and zero before -500 microseconds.

1700420725077.png


In contrast, FL7 has more extended pre-ringing ripples, although very low in level. It also has a much longer and more exaggerated post-ringing, which can be a useful effect with some music.

The default FL2 and FL7 have virtually identical amplitude and impulse response, but FL7 had lower distortion in my measurements. YMMV.

1700420845719.png


I may do some sampling rate comparisons to see if there's a rate that works best with the D-6s. So far, I've not seen much difference, though. In particular, impulse response for 44.1 and 48 kHz look virtually identical. That's not been the case with all ESS DACs I've measured.

Edit: there's a slight time-domain benefit to upsampling 44.1 kHz to 88.2 and 48 kHz to 96 kHz.

1700431804575.png


If you're using Roon, you can use Sample rate conversion to do this easily enough. No need to bother with frequencies above 96 kHz.

1700430745145.png
 
Last edited:

nanook

Member
Joined
Mar 31, 2019
Messages
61
Likes
61
Location
Berlin, Germany
Assume also that DAC device measurements are performed under artificially isolated conditions. The intention is that only the device of interest is measured.
I'm really pleased to watch this technically very profound discussion. :)

I recently measured a Topping E50 from a friend of mine. I am using a relatively cheap ADC and I did see a lot of lines in the spectrum well above the noise floor, that are not harmonics. So I connected a linear regulated lab-power supply instead of the 5V SMPS. All of these lines have disappeared leaving me with the distortion of the E50 and (clearly dominating the picture) the distortion of my cheap ADC.
This measurement was performed single-ended and without USB- isolation - name it "real world".
-> I agree, it is not very likely we obtain the ca. 22bits of this DAC in real life.
Of course, there's not much energy in the "noise" the SMPS introduces, so again it's questionable if this is audible.
 

natna

Member
Joined
Apr 27, 2021
Messages
41
Likes
35
I always like to spend a few weeks listening to a new DAC before taking measurements so that my subjective impressions are not swayed by objective data. After playing with the seven filter settings, I settled on FL3 as sounding the most "right" to my ears. I finally got around to taking some measurements today to see what's what.

TL; DR - avoid filters FL1 and FL6 because of distortion at ~14 kHz and excessive attenuation in the highs. FL3 and FL7 are the most useful. Choose FL3 for most listening, but FL7 may be beneficial with some music, depending on your tastes.


F2 is the default filter. Here's what I see for Amplitude and Impulse response, and Distortion.

View attachment 327860

You'll have to mentally compensate for the inverted horseshoe shared amplitude response. I don't have a great way to compensate for the ADC response of my Focusrite Scarlett 2i2 audio interface, and the vertical scale is only 1 dB, so pretend that this is flat. :)

Impulse response shows extended pre-ringing ripples and exaggerated post-ringing with this filter. No obvious issues with distortion.

With the FL1 and FL6 filters, I'm seeing early attenuation in the high frequencies and a sharp increase in 2nd order distortion at around 14 kHz:

View attachment 327863

I'm not sure how audible this is, but I would avoid FL1 and FL6 for this reason.

After looking at response of all seven filters, FL3 and FL7 are the most useful. FL3 has a little more pre-ringing than I would like, but it's under 5% from -500 to -140 microseconds and zero before -500 microseconds.

View attachment 327865

In contrast, FL7 has more extended pre-ringing ripples, although very low in level. It also has a much longer and more exaggerated post-ringing, which can be a useful effect with some music.

The default FL2 and FL7 have virtually identical amplitude and impulse response, but FL7 had lower distortion in my measurements. YMMV.

View attachment 327866

I may do some sampling rate comparisons to see if there's a rate that works best with the D-6s. So far, I've not seen much difference, though. In particular, impulse response for 44.1 and 48 kHz look virtually identical. That's not been the case with all ESS DACs I've measured.

So, after these measurements, do you like it or not? Or do you think it's worth buying one?
 

dsnyder0cnn

Addicted to Fun and Learning
Joined
Dec 14, 2019
Messages
539
Likes
798
So, after these measurements, do you like it or not? Or do you think it's worth buying one?

I'm totally hooked on this DAC, even before measurements. And, if the measurements were disappointing, I'd still be happy with the sound. ;-)

I've been enjoying the D-6s so much, I'll probably buy another one for my other system (to replace my Gustard X18). The D-6s is the best sounding DAC I've tried so far, including the much more expensive Benchmark DAC3 B and Topping D90SE.

Short answer: Yes
 

natna

Member
Joined
Apr 27, 2021
Messages
41
Likes
35
I'm totally hooked on this DAC, even before measurements. And, if the measurements were disappointing, I'd still be happy with the sound. ;-)

I've been enjoying the D-6s so much, I'll probably buy another one for my other system (to replace my Gustard X18). The D-6s is the best sounding DAC I've tried so far, including the much more expensive Benchmark DAC3 B and Topping D90SE.

Short answer: Yes

Thanks.
Have you tested it via optical or coaxial? Is the volume output via these adequate?
There were reports about other SMSL DACs, that there was low volume via spdif, compared to USB...
 

dsnyder0cnn

Addicted to Fun and Learning
Joined
Dec 14, 2019
Messages
539
Likes
798
Thanks.
Have you tested it via optical or coaxial? Is the volume output via these adequate?
There were reports about other SMSL DACs, that there was low volume via spdif, compared to USB...

I have. Identical output levels and response via both COAX and TOSLINK S/PDIF. For these, I'm using a WiiM Pro streamer, as mentioned above. The WiiM Pro and the D-6s make an excellent pair if you don't care deeply about DSD or PCM above 192 kHz.
 

natna

Member
Joined
Apr 27, 2021
Messages
41
Likes
35
I have. Identical output levels and response via both COAX and TOSLINK S/PDIF. For these, I'm using a WiiM Pro streamer, as mentioned above. The WiiM Pro and the D-6s make an excellent pair if you don't care deeply about DSD or PCM above 192 kHz.
That's great news. Thanks
Wanna use it with Sony UBP-X800M2 Bluray/SACD + my Dynabook Ryzen5 laptop/ LG V40 phone(bit perfect).
I use FLAC mostly 16/44.1 up to 24/96. Nothing too fancy...

Oh! I forgot the Sony mds-je770 md deck. :);)
 

dsnyder0cnn

Addicted to Fun and Learning
Joined
Dec 14, 2019
Messages
539
Likes
798
That's great news. Thanks
Wanna use it with Sony UBP-X800M2 Bluray/SACD + my Dynabook Ryzen5 laptop/ LG V40 phone(bit perfect).
I use FLAC mostly 16/44.1 up to 24/96. Nothing too fancy...

Oh! I forgot the Sony mds-je770 md deck. :);)
You'll love it. Sadly, looks like the $30 off sale is over on apos.audio, but price/performance is still there in spades at $199
 

wavetrade

Member
Joined
Oct 7, 2023
Messages
64
Likes
43
I'm totally hooked on this DAC, even before measurements. And, if the measurements were disappointing, I'd still be happy with the sound. ;-)

I've been enjoying the D-6s so much, I'll probably buy another one for my other system (to replace my Gustard X18). The D-6s is the best sounding DAC I've tried so far, including the much more expensive Benchmark DAC3 B and Topping D90SE.

Short answer: Yes
I had the DL200 and felt the same about it. I think the 9039 chip is dandy. Sadly, my DL200 began popping when turned on, and it was getting louder over time. I wasn't liking this development, particularly with it hooked up to an amp that could send at least 240 watts to each speaker. Thankfully I had two days left for an amazon return and I ordered a DO300 as a replacement. To my ears it sounds dreamy good too. But I am a bit concerned about smsl durability and going to stick with Amazon only for these purchases. Hopefully the D-6s will show up there eventually as I would like one.
 

Esprit

Active Member
Forum Donor
Joined
Apr 11, 2023
Messages
188
Likes
216
Location
Italy
Off topic: where can I find the explanation of the different colors of MQA?
 

nanook

Member
Joined
Mar 31, 2019
Messages
61
Likes
61
Location
Berlin, Germany
Off topic: where can I find the explanation of the different colors of MQA?

Green: This is used by software or hardware that can perform the first MQA unfold (MQA Core). It tells you that even though the MQA file being decoded can be authenticated, the recording engineer hasn’t declared the track to be the definitive version of the recording.

Blue: This is used by software or hardware that can perform the first MQA unfold (MQA Core). It indicates an MQA Studio track, which in addition to being authenticated, is also considered the definitive version of the recording. According to Bob Stuart, “The sound you are hearing is exactly as played in the studio when the music was completed.”

Magenta: This is used by an MQA hardware renderer (or a full decoder) when these devices receive an MQA Core stream from an app or another hardware device that has performed the first unfold. It indicates that the stream has been correctly encoded as an MQA file, but it cannot authenticate it or tell you if it is an MQA Studio track.
 

Jimster480

Major Contributor
Joined
Jan 26, 2018
Messages
2,809
Likes
1,982
Location
Tampa Bay

Green: This is used by software or hardware that can perform the first MQA unfold (MQA Core). It tells you that even though the MQA file being decoded can be authenticated, the recording engineer hasn’t declared the track to be the definitive version of the recording.

Blue: This is used by software or hardware that can perform the first MQA unfold (MQA Core). It indicates an MQA Studio track, which in addition to being authenticated, is also considered the definitive version of the recording. According to Bob Stuart, “The sound you are hearing is exactly as played in the studio when the music was completed.”

Magenta: This is used by an MQA hardware renderer (or a full decoder) when these devices receive an MQA Core stream from an app or another hardware device that has performed the first unfold. It indicates that the stream has been correctly encoded as an MQA file, but it cannot authenticate it or tell you if it is an MQA Studio track.
My D70S isn't that detailed. It just says MQA with a little logo on the screen. The SMSL SU-8S had the little lights.
 

bogi

Active Member
Joined
Sep 16, 2020
Messages
235
Likes
166
Location
Slovakia
Why are you attempting to use dying MQA? No other possibility?
1700559651047.jpeg
 

SiR

Member
Joined
Jan 4, 2022
Messages
58
Likes
16
I have. Identical output levels and response via both COAX and TOSLINK S/PDIF. For these, I'm using a WiiM Pro streamer, as mentioned above. The WiiM Pro and the D-6s make an excellent pair if you don't care deeply about DSD or PCM above 192 kHz.
@dsnyder0cnn is there any specific reason to say this " if you don't care deeply about DSD or PCM above 192 kHz. "

I'm looking for a DAC to pair with my WiiM PRO and considering this DAC but your recommendation is bit disturbing as I have DSD files too and love to listen it

TIA
 

staticV3

Master Contributor
Joined
Aug 29, 2019
Messages
7,112
Likes
11,321
@dsnyder0cnn is there any specific reason to say this " if you don't care deeply about DSD or PCM above 192 kHz. "

I'm looking for a DAC to pair with my WiiM PRO and considering this DAC but your recommendation is bit disturbing as I have DSD files too and love to listen it

TIA
It's because the WiiM does not support DSD or PCM >192kHz.

Edit: Nvm, it does support >192kHz and DSD.
 
  • Like
Reactions: SiR

SiR

Member
Joined
Jan 4, 2022
Messages
58
Likes
16
It's because the WiiM does not support DSD or PCM >192kHz.

Edit: Nvm, it does support >192kHz and DSD.
Welcome your response @staticV3

What if I use DSD files from Laptop connected trough USB to the DAC ?

Then it will not be an issue isn't !!

TIA
 

staticV3

Master Contributor
Joined
Aug 29, 2019
Messages
7,112
Likes
11,321
Welcome your response @staticV3

What if I use DSD files from Laptop connected trough USB to the DAC ?

Then it will not be an issue isn't !!

TIA
The D-6s will play DSD via USB just fine.
Streaming DSD from a WiiM Pro to the D-6s via Coax may be possible as well.

Edit: the WiiM Pro page isn't super clear about that. The Pro Plus page does claim up to 32/768 and DSD512 via Coax though.
 
Top Bottom