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SMSL D-6 DAC Review

Rate this DAC:

  • 1. Poor (headless panther)

    Votes: 4 1.4%
  • 2. Not terrible (postman panther)

    Votes: 10 3.4%
  • 3. Fine (happy panther

    Votes: 90 30.8%
  • 4. Great (golfing panther)

    Votes: 188 64.4%

  • Total voters
    292

LGD_

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Check out the part i quoted, that you wrote. There is no way the AK4493S chip is upsampling PCM to DSD.

I don't need to read an article because I have read the AKM datasheet itself.
You are correct, the DAC chip doesn't up-sample PCM to DSD.
Please re-read what I originally wrote:

I'm up-converting all my FLACs to DSD 256 with Foobar's DSD Processor.

The second article I linked describes this process.
 

Music1969

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Please re-read what I originally wrote:

I'm up-converting all my FLACs to DSD 256 with Foobar's DSD Processor.
Yes you also wrote "The reason it does is that apparently the DAC internally processes everything as DSD, so it must first convert the FLAC (PCM) files to DSD."

that's the part I first replied to and quoted...
 

doug s.

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You are correct, the DAC chip doesn't up-sample PCM to DSD.
Please re-read what I originally wrote:

I'm up-converting all my FLACs to DSD 256 with Foobar's DSD Processor.

The second article I linked describes this process.
so, your initial post is a bit confusing. because you said:
"The reason it does is that apparently the DAC internally processes everything as DSD, so it must first convert the FLAC (PCM) files to DSD."

if i understand this, in fact, this dac is not converting pcm to dsd, it's just playing it as pcm. but, you think it sounds better if converted elsewhere and then played as dsd. i'd posted a link to your post here on another blog, and got the same response as music1969 gave, re: this dac not internally converting pcm to dsd.

doug s.
 

LGD_

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Yes you also wrote "The reason it does is that apparently the DAC internally processes everything as DSD, so it must first convert the FLAC (PCM) files to DSD."

that's the part I first replied to and quoted...
I based what I said on the article I quoted. If you choose not to read it....
 

Music1969

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I based what I said on the article I quoted. If you choose not to read it....
Lol no worries, but the article is completely wrong.

For SMSL D-6, only accurate sources are the user manual and AKM 4493S datasheet
 

Music1969

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but, you think it sounds better if converted elsewhere and then played as dsd.
This is something different - the D-6 does have a DSD Direct mode, where you completely bypass the DAC chip DSP.

So all the DSP is done before the DAC, during the PCM to DSD coversion.
 

LGD_

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so, your initial post is a bit confusing. because you said:
"The reason it does is that apparently the DAC internally processes everything as DSD, so it must first convert the FLAC (PCM) files to DSD."

if i understand this, in fact, this dac is not converting pcm to dsd, it's just playing it as pcm. but, you think it sounds better if converted elsewhere and then played as dsd. i'd posted a link to your post here on another blog, and got the same response as music1969 gave, re: this dac not internally converting pcm to dsd.

doug s

Most modern Delta-Sigma DAC chips can decode multiple file formats, including PCM, DSD, and Wide-DSD. When they are decoding PCM, a Delta-Sigma DAC chip has to first convert it into DSD, the chip's native format. Another reason for the common misconception that DSD performs better than PCM has to do with the poor quality of the real-time PCM to DSD converters built into native DSD Delta-Sigma DACs.
 

LGD_

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This is something different - the D-6 does have a DSD Direct mode, where you completely bypass the DAC chip DSP.

So all the DSP is done before the DAC, during the PCM to DSD coversion.
Yes, as I understand it, it skips a process in the DAC chip by doing it on the PC.
All I know is - it sounds noticeably better to me.
 

doug s.

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Yes, as I understand it, it skips a process in the DAC chip by doing it on the PC.
All I know is - it sounds noticeably better to me.
except in this case, there is NO process skipped in this dac, because this dac chip does NOT have the ability to internally convert pcm data to dsd data...

doug s.
 

Music1969

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except in this case, there is NO process skipped in this dac, because this dac chip does NOT have the ability to internally convert pcm data to dsd data...

doug s.
Im this case he is converting PCM to DSD with JRiver
 

rentaclaus

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Here you can find a lenghty discussion about the obstacles of supporting native DSD in pipewire (a linux soundsystem) and the question if this would make sense or is only a waste of time and efforts. Seems things are more complicate ...

 

LGD_

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Here you can find a lenghty discussion about the obstacles of supporting native DSD in pipewire (a linux soundsystem) and the question if this would make sense or is only a waste of time and efforts. Seems things are more complicate ...

Thanks for the link. Interesting, but he's discussing digital volume controls here - not exactly what I'm doing.
But he does indicate a preference for outboard processing.
 

LGD_

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except in this case, there is NO process skipped in this dac, because this dac chip does NOT have the ability to internally convert pcm data to dsd data...

doug s.
OK...
I confess that most of the data sheet is over my head,
But I don't see anything in there that says HOW the chip processes PCM (that I can understand, anyway).
I based my knowledge on the article, which you say is wrong, How so ?

Is this chip a "delta-sigma" type ?? I'm assuming it is, since it's not a resistor-ladder type, and he indicates that most DACs are one or the other.
Maybe this is no longer true ?? (the article is from 2015).

So are you saying that the chip does not process everything internally as DSD, as he indicates ?
All I see, in the block diagram is a "PCM data interface". How do you know that this block doesn't convert PCM to DSD, ahead of the DSD demodulator ?

Respectfully, just trying to learn...
 
Last edited:

decomo

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Feb 2, 2022
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Can anyone enlighten me what PCM Filter Range FL1 to 6 and Setting the Tone SC1 to 4 are for?

The manual says for Filter Range as below;

FL1(Sharp Roll-off filter)
FL2(Slow Roll-off filter)
FL3(Short Delay Sharp Roll-off filter)
FL4(Short Delay Slow Roll-off filter)
FL5(Super Slow Roll-off filter)
FL6(Low Dispersion Short Delay filter )

Not what what these are mean and does it makes noticeable difference among each other?

The manual does not say anything about Setting the tone SC1 to 4 so not sure what these are for.

Thank you very much in advance.
 

LGD_

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Can anyone enlighten me what PCM Filter Range FL1 to 6 and Setting the Tone SC1 to 4 are for?

The manual says for Filter Range as below;

FL1(Sharp Roll-off filter)
FL2(Slow Roll-off filter)
FL3(Short Delay Sharp Roll-off filter)
FL4(Short Delay Slow Roll-off filter)
FL5(Super Slow Roll-off filter)
FL6(Low Dispersion Short Delay filter )

Not what what these are mean and does it makes noticeable difference among each other?

The manual does not say anything about Setting the tone SC1 to 4 so not sure what these are for.

Thank you very much in advance.
I have not been able to hear any difference, when playing PCM files, with any of these (FL1 - FL6) so I just leave it in the default (#1).
The SC 1 - SC4 selections, however do make a (slight) audible difference so I do use them.
But I haven't seen any explanation of exactly what they're changing. The manual is useless, no info there.
 

decomo

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I have not been able to hear any difference, when playing PCM files, with any of these (FL1 - FL6) so I just leave it in the default (#1).
The SC 1 - SC4 selections, however do make a (slight) audible difference so I do use them.
But I haven't seen any explanation of exactly what they're changing. The manual is useless, no info there.

Thank you. I had this unit for over a month now and did not even realise there were setting until last night.

Yes, manual does not say anything about Setting the Tone option SC1 to SC4. I believe that someone in this thread mention that SC2 and FL6 sounds more like hifi setting (?).

My guess is that all of recent SMSL DAC may have these features (default feature in their dac) so another manual may have explanation what SC1 to SC4 are for..
 

xeizo

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Thank you. I had this unit for over a month now and did not even realise there were setting until last night.

Yes, manual does not say anything about Setting the Tone option SC1 to SC4. I believe that someone in this thread mention that SC2 and FL6 sounds more like hifi setting (?).

My guess is that all of recent SMSL DAC may have these features (default feature in their dac) so another manual may have explanation what SC1 to SC4 are for..

It's not an SMSL feature, it's built into the DAC chip by AKM. SMSL has just allowed the user to change those settings in the UI.

The six different digital filters have different sharpness which can be seen in a frequency curve, only the sharpest kills everything above 22kHz. But filters do not only affect frequency response but also ringing/pre-ringing of the waveform, some are sensitive to this and will hear a difference, others will not. AKM describes it as a too sharp filter will make fast transients to have less spatial definition, meaning a less controlled stereo image and they mean some will take the disadvantages with less sharp for the better stereo definition. All this is described on the AKM website.

The "scenes" SC1-SC4 is more of a mystery, it's sort of like a tone control but a extreme slight one. I suppose it's the AKM response to ESS various "tube" sound and such. Maybe some added harmonics or something like that, still a mystery but should be regarded like a "tone control" meaning not transparent in all settings.
 
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