SMSL SU-1 Stereo DAC Review

[Roland68]

USB Standards, Speeds and Cable Length Limits​

https://www.eaton.com/us/en-us/products/data-video-cables-accessories/usb--thunderbolt-and-lightning-cables/usb-cable-maximum-length.html

But that doesn't help with cables that are built too cheaply, regardless of whether they are certified or not. And I'm only talking about a few cents/meter that were saved in production.
In my time in IT, I had to send back boxes of certified USB 2.0 cables with lengths of 2, 3, 4 and 5m, which even caused problems with printers, not to mention keyboards and mice.
With high-quality cables, I had no problems at all, neither in IT nor with DACs, even with 8m long cables.

As I recently discovered with cheap and supposedly certified USB 3.2 (5/10/20 Gbit/s, 2 and 3m) cables from Amazon, this hasn't changed. I had to send back 3 out of 4 cables because of massive problems.

 

[Doodski]

But that doesn't help with cables that are built too cheaply, regardless of whether they are certified or not. And I'm only talking about a few cents/meter that were saved in production.
In my time in IT, I had to send back boxes of certified USB 2.0 cables with lengths of 2, 3, 4 and 5m, which even caused problems with printers, not to mention keyboards and mice.
With high-quality cables, I had no problems at all, neither in IT nor with DACs, even with 8m long cables.

As I recently discovered with cheap and supposedly certified USB 3.2 (5/10/20 Gbit/s, 2 and 3m) cables from Amazon, this hasn't changed. I had to send back 3 out of 4 cables because of massive problems.

I bought Starlink USB 2.0 15 footers and they work fine for the printer. I was concerned they would be flaky but I was lucky.

 

[musica]

Recommend me a high-quality USB-C to USB-A 2.0 cable of 3 meters.

 

[staticV3]

Recommend me a high-quality USB-C to USB-A 2.0 cable of 3 meters.

Delock 85209

 

[Roland68]

Recommend me a high-quality USB-C to USB-A 2.0 cable of 3 meters

LINDY 36888 3 m USB 2.0 Type C to A Cable, Anthra Line Black
Make sure you get a real USB 2.0 cable, like the Delock or the Lindy.

 

[musica]

How can I make the SU-1 play the native DSD format without any conversion?

.

 

[Deleted member 77012]

How can I make the SU-1 play the native DSD format without any conversion?

You can’t, as the S.M.S.L SU-1 playback signal is analog.

 

[staticV3]

How can I make the SU-1 play the native DSD format without any conversion?

.

See here:

Topping E50 Review (Balanced DAC)

Sorry if this was already discussed, but is hard to read all 94 pages: can Topping E50 be fed only by the USB connection to the PC (cable length = 1.5m), without an external power supply ? Yeap! Here, it works fine with its original power cable on a Mac Mini

www.audiosciencereview.com

And replace the Topping driver with SMSL's driver.

 

[audioenthousiast1988]

If one of the three inputs is unusable — especially the one that is used to connect with a PC, mobile phone, etc. — then it is a serious flaw, one that disqualifies it from my usage and recommendation.

Have you viewed my video documenting the problem? This clip is made with the C100, but the SU-1 has the same problem. The C100 was fixed with a firmware update. It's not unrealistic to assume the SU-1 can be fixed similarly.

im trying to update the firmware but i cant seem to get the smsl su 1 in 'upgrade' mode when i connect it to the laptop. the instructions seem vague and not specific to the smsl su 1. could you help me ?

 

[Roland68]

im trying to update the firmware but i cant seem to get the smsl su 1 in 'upgrade' mode when i connect it to the laptop. the instructions seem vague and not specific to the smsl su 1. could you help me ?

Where did you get a firmware for the SU-1? I haven't seen any yet.

If you use a different one that isn't specifically for the SU-1, the device may no longer work. And that isn't covered by the warranty.

 

[blunile]

I did the same thing, but I came to the conclusion that replacing the opa doesn’t make sense, i made the converters so small that they fit underneath.

I agree with you. If you already know which op amp you are sticking with, what you did is definitely a better way.

 

[alexanderino]

could you help me ?

Sorry, mate. I returned the SU-1 a long time ago and moved on to the C100.

 

[Jimster480]

I honestly can't believe how this is on sale for $70 still in 2025. I think it makes a great DAC option to upgrade something like the Denon Link which has kind of poor SINAD from its internal DAC.

 

[Roland68]

I honestly can't believe how this is on sale for $70 still in 2025. I think it makes a great DAC option to upgrade something like the Denon Link which has kind of poor SINAD from its internal DAC.

I would still recommend the slightly more expensive and newer C100.
The SU-1 can sometimes be annoying with a few crackling noises.
After switching to the C100, this problem completely disappeared. For one thing, the C100 has newer firmware, and since the C100 was released later, hardware improvements can't be ruled out.
A remote control, display, and Bluetooth are included as bonuses.

 

[Jimster480]

I would still recommend the slightly more expensive and newer C100.
The SU-1 can sometimes be annoying with a few crackling noises.
After switching to the C100, this problem completely disappeared. For one thing, the C100 has newer firmware, and since the C100 was released later, hardware improvements can't be ruled out.
A remote control, display, and Bluetooth are included as bonuses.

Well this C100 is twice the price... Then the market really opens up for competition and it is all way beyond what I would need anyway as I am basically just taking the output of my Denon Link and feeding it into my sound bar or future speakers. The DAC in the Denon Link just isn't great, but it also isn't terrible... so to "fix it" for $70 is acceptable. Once I get into a price of $120.... that is nearly what I paid for the link itself (2nd hand) and as I mentioned, the picking of a DAC becomes way more complex.

 

[Roland68]

Well this C100 is twice the price... Then the market really opens up for competition and it is all way beyond what I would need anyway as I am basically just taking the output of my Denon Link and feeding it into my sound bar or future speakers. The DAC in the Denon Link just isn't great, but it also isn't terrible... so to "fix it" for $70 is acceptable. Once I get into a price of $120.... that is nearly what I paid for the link itself (2nd hand) and as I mentioned, the picking of a DAC becomes way more complex.

There seem to be very different prices.
The SU-1 costs €79 here on Amazon. The C100 was last listed for €109.90, but I paid €84 on sale.

On Aliexpress, I see prices of €140-150, but at Audiophonics, it's only €115, and at AOSHIDA, it's $119.

 

[Jimster480]

There seem to be very different prices.
The SU-1 costs €79 here on Amazon. The C100 was last listed for €109.90, but I paid €84 on sale.

On Aliexpress, I see prices of €140-150, but at Audiophonics, it's only €115, and at AOSHIDA, it's $119.

Yep here it is $69 for SU-1 and $119 for C100. So not actually twice the price (my mistake).
At a price of $99 there is the E30 II Lite, and a few other products like Topping DX-1.
Then there is Sabaj A20h (which goes on sale for $89 frequently) and SMSL M300SE.

There are even more than this if I look at Fosi, FiiO, Loxjie and others

 

[theREALdotnet]

I guess it depends on whether the added features are desirable. I use three SU-1s stacked on top of each other. I like their almost-not-there appearance. They produce faint clicks on sample rate changes, but that happens only between some albums and doesn't bother me much. If I were to replace them with C100s (about 80% more expensive here) then the Bluetooth antennas would never leave the boxes, and the displays would be distracting, hence be turned off or taped over.

 

[Jimster480]

I guess it depends on whether the added features are desirable. I use three SU-1s stacked on top of each other. I like their almost-not-there appearance. They produce faint clicks on sample rate changes, but that happens only between some albums and doesn't bother me much. If I were to replace them with C100s (about 80% more expensive here) then the Bluetooth antennas would never leave the boxes, and the displays would be distracting, hence be turned off or taped over.

Yes see I like the SU-1 not having a screen or anything else. It would sit under or behind my Denon Link which is behind my TV. The box itself is small enough and I would never need to interact with it.

 

[Roland68]

I guess it depends on whether the added features are desirable. I use three SU-1s stacked on top of each other. I like their almost-not-there appearance. They produce faint clicks on sample rate changes, but that happens only between some albums and doesn't bother me much. If I were to replace them with C100s (about 80% more expensive here) then the Bluetooth antennas would never leave the boxes, and the displays would be distracting, hence be turned off or taped over.

Unfortunately, the clicking noises were the problem with the SU-1. The noise on my headphones was so loud it was really unpleasant. It always depends on the components. But for me, it was only a €5 difference.

Are you using the three SU-1 for an active system via USB?

Yep here it is $69 for SU-1 and $119 for C100. So not actually twice the price (my mistake).
At a price of $99 there is the E30 II Lite, and a few other products like Topping DX-1.
Then there is Sabaj A20h (which goes on sale for $89 frequently) and SMSL M300SE.

There are even more than this if I look at Fosi, FiiO, Loxjie and others

The Sabaj A20h is a HPA, but if you can get an older A20d (same chassis as the A20h) for that price, you should go for it. You won't find a symmetrical ES9038Pro for that price anywhere else.