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SMSL D400ES and SMSL D400Ex

Amazon and Sweetwater just had the RME ADI-2 DAC FS for 1036 around Black Friday. I had one ordered for 1399 and quickly cancelled that order. I now have that DAC sitting in front of me and no longer concerned with anything else after many months of obsessing.
I tried the RME back when I was shopping for the Topping D90 (AK4499). I thought they sounded damn near identical for my music preferences. Kept the D90 because it a few hundred $$ cheaper and I had no need for a strong headphone amp.

Found another forum thread on the D400EX at Head-Fi. One guy in particular (HermannS) offers some pretty detailed commentary on the dac. He likes it very much.

"Alright, the DAC had time to break in for three days and it seems to settle. Time to wrap up my experiences so far.

I am listening through a dCS network bridge, a Benchmark HPA4, and a pair of Focal SM9. All devices are a little to substantially modified by myself. The FLAC files are streamed via JRiver MediaServer from a PC. I am using a convolving filter (room correction) on the files at runtime. The filters were produced by the Acourate Audio Vero software.

I’ve listened to ESS-based DACs for 8 years now (Benchmark DAC2, Musetec 005, Topping D90SE) and it took me a while to understand the difference in sound quality, because the D400EX is something else.

Let’s make a big fat checkmark next to: resolution, transparency, soundstage, precision, neutrality. Don't worry, you will get lots of that and there is no point in describing it with colorful words, which everybody understands differently.

The biggest “wow” for me is the base and lower mid region. Oh my, it just loves drums and base guitars! The timing feels right in the pocket and it is easier for me to follow base lines and all those deep rumblings than ever before. Absolutely fantastic. This is its major strength.

The highs are so clean that I rarely focus on them. Sometimes they felt a little detached, but that gradually became better with break-in. It is always hard to tell whether the recording is to blame or the gear when sibilants sound weird. It requires many, many samples and cross-checks to find the culprit.

Also interesting is the large spread between silence and full attack. At first I sometimes felt “this sounds lame” and pulled the volume up. However, when a recording has real dynamics, the D400 will throw that at you! The D400 is free of what I call "loudness effects", which emphasize silent parts, but are a lie nevertheless.

Another big “wow” is the richness, or plasticity if you will, of instruments and voices. In contrast to an ESS DAC the D400 does not add edges to everything, it sort of fills the bodies from the inside. On some tracks, which I know inside-out, voices suddenly have volume and radiate into the sound stage. They are not thin points anymore.

All that without sounding fuzzy or imprecise. The opposite is true. I listen to a lot of dense, compressed Rock music and the D400 has no trouble sorting everything out and keeping it nailed down. ESS DACs can do that, too, but in a totally different way. They rather stamp out the components with a crisp contour. The D400 does not produce such contours. Here is where you may call it “smooth”.

But make no mistake, the D400 is not what some might call pleasing, “analog-sounding”. It sounds crystal clear and somewhat bright even. It is not very gentle to crappy recordings, however more forgiving than the D90SE, for example.

This is where I have trouble describing what I am hearing. On the one hand the sound is rich and powerful with full detail. But there is this slight lack of texture in the upper mids, which can sometimes make voices sound a bit bright and distorted guitars a little flat and missing the “fuzzy crunch”.

The PCM filter settings have an influence on this. I generally prefer sharp filters. My current favorite is “low dispersion”, which is kind of a mix of everything. You’ll find interesting blog posts about the AKM filters with measurements. The slow filters smoothen things out, but with a loss of precision, at least that’s how I hear it. They just sound too lame for me.

What I miss a little from the Topping DS90SE is the typical “ESS attack”. The ESS DACs add a touch of drama to everything. This can be fun and exciting, especially with rock guitars. It can be annoying when this sort of (artificial?) crispiness does not fit the music. Compared side-by-side the D400 can sound a little dull sometimes when you are used to the attack, but being totally honest, after listening to many tracks, it feels more realistic and believable.

To sum up:
Performance / price ratio is off the charts. This DAC could make big waves in the scene. It easily leaves the Benchmark DAC2 with hefty mods, the Musetec 005, and the Topping D90SE with plenty of mods in the dust. Just like that, unmodified. For me there is no going back.
However, nothing is perfect and I think the tonally critical upper midrange is affected by some cheap capacitors, although SMSL has already used good stuff from what I saw on the images.

It will be opened and examined soon. I am very happy about my choice and it is a promising modding project for the winter."

 
But why does the AKM one only support DSD512 and pcm 768khz? Aren't those supposed to support DSD1024 and PCM 1536?
Both formats are useless waste of storage. When it was the last time you downloaded something dsd512 or pcm 768?
 
Both formats are useless waste of storage. When it was the last time you downloaded something dsd512 or pcm 768?

I like to upsample everything in roon :)
Doesn't need to be always useful...but I like to watch the cpu usage of my roon core.. I'm strange that way, I know
 
I tried the RME back when I was shopping for the Topping D90 (AK4499). I thought they sounded damn near identical for my music preferences. Kept the D90 because it a few hundred $$ cheaper and I had no need for a strong headphone amp.

Found another forum thread on the D400EX at Head-Fi. One guy in particular (HermannS) offers some pretty detailed commentary on the dac. He likes it very much.

"Alright, the DAC had time to break in for three days and it seems to settle. Time to wrap up my experiences so far.

I am listening through a dCS network bridge, a Benchmark HPA4, and a pair of Focal SM9. All devices are a little to substantially modified by myself. The FLAC files are streamed via JRiver MediaServer from a PC. I am using a convolving filter (room correction) on the files at runtime. The filters were produced by the Acourate Audio Vero software.

I’ve listened to ESS-based DACs for 8 years now (Benchmark DAC2, Musetec 005, Topping D90SE) and it took me a while to understand the difference in sound quality, because the D400EX is something else.

Let’s make a big fat checkmark next to: resolution, transparency, soundstage, precision, neutrality. Don't worry, you will get lots of that and there is no point in describing it with colorful words, which everybody understands differently.

The biggest “wow” for me is the base and lower mid region. Oh my, it just loves drums and base guitars! The timing feels right in the pocket and it is easier for me to follow base lines and all those deep rumblings than ever before. Absolutely fantastic. This is its major strength.

The highs are so clean that I rarely focus on them. Sometimes they felt a little detached, but that gradually became better with break-in. It is always hard to tell whether the recording is to blame or the gear when sibilants sound weird. It requires many, many samples and cross-checks to find the culprit.

Also interesting is the large spread between silence and full attack. At first I sometimes felt “this sounds lame” and pulled the volume up. However, when a recording has real dynamics, the D400 will throw that at you! The D400 is free of what I call "loudness effects", which emphasize silent parts, but are a lie nevertheless.

Another big “wow” is the richness, or plasticity if you will, of instruments and voices. In contrast to an ESS DAC the D400 does not add edges to everything, it sort of fills the bodies from the inside. On some tracks, which I know inside-out, voices suddenly have volume and radiate into the sound stage. They are not thin points anymore.

All that without sounding fuzzy or imprecise. The opposite is true. I listen to a lot of dense, compressed Rock music and the D400 has no trouble sorting everything out and keeping it nailed down. ESS DACs can do that, too, but in a totally different way. They rather stamp out the components with a crisp contour. The D400 does not produce such contours. Here is where you may call it “smooth”.

But make no mistake, the D400 is not what some might call pleasing, “analog-sounding”. It sounds crystal clear and somewhat bright even. It is not very gentle to crappy recordings, however more forgiving than the D90SE, for example.

This is where I have trouble describing what I am hearing. On the one hand the sound is rich and powerful with full detail. But there is this slight lack of texture in the upper mids, which can sometimes make voices sound a bit bright and distorted guitars a little flat and missing the “fuzzy crunch”.

The PCM filter settings have an influence on this. I generally prefer sharp filters. My current favorite is “low dispersion”, which is kind of a mix of everything. You’ll find interesting blog posts about the AKM filters with measurements. The slow filters smoothen things out, but with a loss of precision, at least that’s how I hear it. They just sound too lame for me.

What I miss a little from the Topping DS90SE is the typical “ESS attack”. The ESS DACs add a touch of drama to everything. This can be fun and exciting, especially with rock guitars. It can be annoying when this sort of (artificial?) crispiness does not fit the music. Compared side-by-side the D400 can sound a little dull sometimes when you are used to the attack, but being totally honest, after listening to many tracks, it feels more realistic and believable.

To sum up:
Performance / price ratio is off the charts. This DAC could make big waves in the scene. It easily leaves the Benchmark DAC2 with hefty mods, the Musetec 005, and the Topping D90SE with plenty of mods in the dust. Just like that, unmodified. For me there is no going back.
However, nothing is perfect and I think the tonally critical upper midrange is affected by some cheap capacitors, although SMSL has already used good stuff from what I saw on the images.

It will be opened and examined soon. I am very happy about my choice and it is a promising modding project for the winter."

Interesting. But e Topping DS90SE is the typical “ESS attack”.
I do not see any "ESS atack on 4V mode." On 5V everyrhing differs. I do not like it on modern drums like Iron Maiden 2010. Sound to studio. But D90LE sounds natural anyway. I want to hear D400 by my own. I have SMSL M300MK2 also.
The ESS DACs add a touch of drama to everything.
Maybe on 5V mode. But I do not agree.
 
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Bad news for mine. The left channel stopped working suddenly. I updated the firmware, but haven't changed a single setting from the factory defaults. It just winked out while playing some N-I-N this afternoon. Already contacted Apos to get an RMA going. I'm just going to take a refund instead of a replacement. I love the sound, so I'll look for the Gustard A26 which has the same AK dac configuration.
 
Bad news for mine. The left channel stopped working suddenly. I updated the firmware, but haven't changed a single setting from the factory defaults. It just winked out while playing some N-I-N this afternoon. Already contacted Apos to get an RMA going. I'm just going to take a refund instead of a replacement. I love the sound, so I'll look for the Gustard A26 which has the same AK dac configuration.
One site mentions "network Streamer" as a feature. Maybe it's roon ready like the R26
 
Bad news for mine. The left channel stopped working suddenly. I updated the firmware, but haven't changed a single setting from the factory defaults. It just winked out while playing some N-I-N this afternoon. Already contacted Apos to get an RMA going. I'm just going to take a refund instead of a replacement. I love the sound, so I'll look for the Gustard A26 which has the same AK dac configuration.
Sad. I have D90LE but I want to hear some nice AK DAC also.
 
Bad news for mine. The left channel stopped working suddenly. I updated the firmware, but haven't changed a single setting from the factory defaults. It just winked out while playing some N-I-N this afternoon. Already contacted Apos to get an RMA going. I'm just going to take a refund instead of a replacement. I love the sound, so I'll look for the Gustard A26 which has the same AK dac configuration.
Is that out yet, as in available for purchase?
 
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Is that out yet, as in available for purchase?
Haven't seen it for purchase yet. My guess is it'll be out sometime closer to Christmas.
 
For the "all sound are in the very low volume" issue, I've experienced at the first time installed, but then solved it in 5 mins.

I personally use ubuntu 22, which uses ALSA as the underlying audio driver.

Here is how to adjust it:

1. Open application `terminal` from your OS
2. Type command `alsamixer`, then hit Enter
3. Press F6 for Select sound card, Choose "SMSL USB AUDIO" then Enter
4. Use arrow key up/down to adjust the master volume
5. When you finished, just press Esc to leave, it will be saved automatically.

Screenshot from 2022-12-07 00-10-46.png



If I recall correctly, the first time I enter alsamixer, it set SMSL USB DAC to the volume level at around 20ish, after set to 100 ( 0db ), the volume problem are gone.

Guess somehow the firmware not telling the OS system to set the default master volume to higher value.
Maybe the MacOS has the similar issue ( Unix-like OS does not need to install official XMOS driver ), and may have adjust the same way.

This may occur in other devices. ( maybe equipeed with the same usb chip without thoroughly QA I guess? )
So for people are interested in set the default volume for all devices, check: https://unix.stackexchange.com/a/211071 ( Not tried yet )

I only experienced "ALL sound are in the very low volume", not by track nor by channel, so far so good, no additional issue, and really satisfied with it currently. compared with my old smsl su-9, especially highlight at my personal feeling: detail / sound stage (3d fell) / mid-tone and overtone for string-based instruments. sound field is narrow, but that's the monitoring style which I like.

Hope this help. keep audiophiling :)

I finally registered an account for this thread :p
 
Nope, I'm using the fresh factory setup.

Not sure if it's related, my device configured as fixed-volume in the pre-mode

edit:

FYI

PC -> USB in -> D400ex pre mode fixed volume -> XLR out
That’s exactly the way I used it with my computer. Anyway I got it replaced by Apos, so I’d check it once it arrives..
 
For the "all sound are in the very low volume" issue, I've experienced at the first time installed, but then solved it in 5 mins.

I personally use ubuntu 22, which uses ALSA as the underlying audio driver.
Use pipewire for bitmatched playback without resampling.
 
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