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SMSL SU-6 Review (Desktop DAC)

pwn87

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Seems like currently I can get the SU-9N on Amazon for €329.. That's why I'm tempted..

I'm not going to let a standby LED be the deciding factor haha. Can the screen of the SU-9N be completely dimmed?
yeah you can change brightness and screen timeout.
the su-6 has a brightness setting, but i'm not sure if the screen timeout can be turned off. (which is unfortunate because that white text looks damn cool)
 
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Jerderv

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I wish the default display was switchable. Id really rather have the volume displayed instead of the bit rate personally.

Also I cant find an IR setting for my amazon fire remote that controls the SU-6. I was able to control the Q5 pro with the amazon remote with the first SMSL group setting. Hopefully amazon will update soon. I wonder if SMSL provided the updated IR information if amazon would add that sooner than later. I tried multiple other IR groups thinking I might get lucky but I haven't stumbled upon one yet.
 

Acerun

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I speculate that the USB-C implementation of the DAC is defective, specifically for USB-C cables that have E-Marker chip. For context, the USB-C standard requires that any cable that is able to deliver over 3A has to include an E-Marker chip, and some devices, potentially the SU-6, are designed in a way that doesn't support these cables. The DAC may still connect over USB-C if the cable doesn't include E-Marker (which is optional for cables that are designed to deliver 3A or below).

I am experiencing the same issue when trying to connect the DAC to my Mac. Unfortunately, I cannot verify this theory since all my USB-C cables are cable to reach 100W (i.e., 5A), but this is a relatively common design issue with devices that support USB 2.0 speeds while providing the USB-C ports.
I will try a non-E marker cable but I actually don't think this is the issue. This is a very well known and well lamented problem with the new pixels. There's a bug that doesn't allow the raw audio signal to flow out of the USB port like it does on most any other modern phone.
 

Jerderv

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When using Bluetooth connected to my Samsung s10, the first time you hit play or after having the music paused for several minutes and hit play. The output stutters and skips for a second or two.
 

Acerun

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When using Bluetooth connected to my Samsung s10, the first time you hit play or after having the music paused for several minutes and hit play. The output stutters and skips for a second or two.
Same thing happens to me on my Pixel 6
 

pieterv1

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Took the plunge with "just" the SU-6 instead of the SU-9n. My main reason to buy a new DAC at this time, was practicality - to get rid of the Topping E30 with its standby function which doesn't really work well in combination with smart sockets to control power to my setup.

I don't have use for balanced connections either and much prefer the minimalistic LED display of the SU-6 :)

A noticeable increase in sound quality from the Topping E30 would be a nice added bonus
 

tvrgeek

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USB C can delver enough Power to charge a modern PC this needing an extra power supply makes no sense to me.

Performance is good I like the Design and that it has a Coax input.
But without balanced out this one is not for me.
It has a fiber and coax input so by definition needs external power. I am sure for more money, SMSL would provide more features like powering options, balanced outputs, preamp controls etc. Seems everyone wants more features for free on a budget priced, very high performance product. Features cost money.
 

pieterv1

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And may point was this is not need.
They shuld just use the standard.
There's plenty of other USB powered options out there. I like that for the SU-6, SMSL used a built-in power supply, similar to what's in their more expensive options. It is custom made, especially for the DAC to to get the best performance out of it. With USB power you never know if people are using crappy or quality chargers.

USB was never "the standard" for audio use to begin with..
 

Lambda

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With USB power you never know if people are using crappy or quality chargers.
With AC you never know what Crappy supply your having at home...
So better get a ps audio power plant :p

Its not a problem to make the device virtually Immune to to input power quality.

As this example showes:

It is easily possible to power 4 channel DACs, A headphone amplifier, Balanced outputs, 4 channel ADCs, 48V phantom power, and LCD from one USB port.

SMSL would provide more features like powering options, balanced outputs, preamp controls etc. Seems everyone wants more features for free on a budget priced, very high performance product. Features cost money.
Actually i'm arguing for a feature to be removed.
The internal power supply.
 

Acerun

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I speculate that the USB-C implementation of the DAC is defective, specifically for USB-C cables that have E-Marker chip. For context, the USB-C standard requires that any cable that is able to deliver over 3A has to include an E-Marker chip, and some devices, potentially the SU-6, are designed in a way that doesn't support these cables. The DAC may still connect over USB-C if the cable doesn't include E-Marker (which is optional for cables that are designed to deliver 3A or below).

I am experiencing the same issue when trying to connect the DAC to my Mac. Unfortunately, I cannot verify this theory since all my USB-C cables are cable to reach 100W (i.e., 5A), but this is a relatively common design issue with devices that support USB 2.0 speeds while providing the USB-C ports
 

Acerun

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I speculate that the USB-C implementation of the DAC is defective, specifically for USB-C cables that have E-Marker chip. For context, the USB-C standard requires that any cable that is able to deliver over 3A has to include an E-Marker chip, and some devices, potentially the SU-6, are designed in a way that doesn't support these cables. The DAC may still connect over USB-C if the cable doesn't include E-Marker (which is optional for cables that are designed to deliver 3A or below).

I am experiencing the same issue when trying to connect the DAC to my Mac. Unfortunately, I cannot verify this theory since all my USB-C cables are cable to reach 100W (i.e., 5A), but this is a relatively common design issue with devices that support USB 2.0 speeds while providing the USB-C ports.
I received the non e-marker cable and it it didn't make any difference. I'm afraid the problem is within the Pixel phones. Google tech support also is dismissive of " The expectation of using cheap DACs from Amazon" so this appears to be a low priority problem for Google.
 

pieterv1

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I received the non e-marker cable and it it didn't make any difference. I'm afraid the problem is within the Pixel phones. Google tech support also is dismissive of " The expectation of using cheap DACs from Amazon" so this appears to be a low priority problem for Google.
Ughhh sad to see how bad the Pixel 6 lineup seems to cope with external DAC's, high quality earbuds etc... Let's just hope these are all still bugs due to the switch to the Tensor chipset rather than actual cost savings.. + fingers crossed they get fixed over time

I thought I had gone with a golden combo, best of both worlds with the Pixel 6 and Sony WF-1000XM4 earbuds. Turns out LDAC doesn't work between these two. I'm very curious to see how LDAC from my Pixel 6 to the SMSL SU-6 will perform. Has anyone tried it?
 

Acerun

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Ughhh sad to see how bad the Pixel 6 lineup seems to cope with external DAC's, high quality earbuds etc... Let's just hope these are all still bugs due to the switch to the Tensor chipset rather than actual cost savings.. + fingers crossed they get fixed over time

I thought I had gone with a golden combo, best of both worlds with the Pixel 6 and Sony WF-1000XM4 earbuds. Turns out LDAC doesn't work between these two. I'm very curious to see how LDAC from my Pixel 6 to the SMSL SU-6 will perform. Has anyone tried it?
Yes, I use LDAP to the SU-6 via my Pixel 6. Sound quality is good to my ears. Only issue is upon first play and sometimes switching "albums" there is a second or two glitch where the first second or two of the song is cut off. After that, smooth playback. Not sure if there is a setting that I can change that can help there.
 

pieterv1

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Yes, I use LDAP to the SU-6 via my Pixel 6. Sound quality is good to my ears. Only issue is upon first play and sometimes switching "albums" there is a second or two glitch where the first second or two of the song is cut off. After that, smooth playback. Not sure if there is a setting that I can change that can help there.
With the WF-1000XM4 there's two issues:
- LDAC quality higher than 330kbps will stutter (not the case with my 3y old Huawei - it does 990kbps effortlessly)
- left earbud audio dropping out until you restart app/resume playback

Have you confirmed you are in fact using LDAC? There's a toggle for this in the Bluetooth settings. Additionally, you can force a specific bitrate from within the developer options
 

Acerun

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With the WF-1000XM4 there's two issues:
- LDAC quality higher than 330kbps will stutter (not the case with my 3y old Huawei - it does 990kbps effortlessly)
- left earbud audio dropping out until you restart app/resume playback

Have you confirmed you are in fact using LDAC? There's a toggle for this in the Bluetooth settings. Additionally, you can force a specific bitrate from within the developer options
Yes. Pixel set to LDAC and SU-6 display shows ld. Pixel shows high bit rate. Just stutters at the start of the first song then smooth.
 

pieterv1

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Today I received the SU-6. First track to send through it, was D'Angelo's Brown Sugar from CD, through optical. I've already sold my E30 so couldn't do a direct comparison, but what struck me was the "air" in the tambourines. Overall sound has a nice amount of body to it. I've ordered some new RCA's from Ali, as suggested by Youtuber "Михаил Греков" (video - watched with automatic translations, which works surprisingly well hehe).

Power cycling works great: AC ON = DAC ON, simple as that ;)

One question: does the DAC have an option to switch between preamp mode & DAC mode, like the Topping E30? Or should I just leave it at 0dB and just assume there's no quality loss?

I also tested LDAC over Bluetooth with my old Huawei P20 Pro & Google Pixel 6 and the SU-6.. The Pixel 6 definitely can't handle 990kbps (24bit), no problem with the Huawei.. But this has become a well known problem with the Pixel 6 lineup.
 
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