SMSL SU-9 Balanced DAC Review

[SashaR]

I contacted S.M.S.L about the poor three foot design of the SU-9. They asked me to contact the dealer I bought it from (SHENZHEN Audio) and have them request extras be sent to me. I did so, and SHENZHEN shipped 8 extra factory feet to me at no charge. I had them 8 days later.

Since I only need 2 feet (I added them to the single foot on the rear of the DAC) and will keep 2 as spares, I have 4 available. If you live in the U.S. and need a couple, shoot me a PM and I'll mail them to you free of charge.

You are a delightful person! I wish you many, many years of absolute health and happiness!

(I'm not an American, thank you for the offer of help! And the legs will be useful to someone else, thank you for your kind heart!)

 

[Veri]

Reason for asking is that my old E30 DAC, which outputs 2V, were able to drive my Drop HD 6XXX headphones fine

Most DACs are not able to directly drive headphones and would suffer a major hit in volume by connecting headphones to them, as well as possible increase in distortion etc, because they're meant to connect to an amplifier over line-out. I guess some DACs are up to the task though. But it's not really recommended..

 

[SashaR]

Most DACs are not able to directly drive headphones and would suffer a major hit in volume by connecting headphones to them, as well as possible increase in distortion etc, because they're meant to connect to an amplifier over line-out. I guess some DACs are up to the task though. But it's not really recommended..

Excuse me please for the continuation ... Whether the headphones with 62 ohms can work with SU9 without distortion and problems? This is AKG K712 (pro) with a mini-XLR male interface on them (see pic.), equipped with a 3-ring 3.5 mm interface cable. The manufacturer: Sensitivity (dB SPL/V @ 1 kHz) = 105. Maximum input power = 200 mW.

I would prefer to use the XLR output of the SU 9 for headphones, because I use the RCA output to connect the SU 9 to an AV receiver. Could all of this be reliable and sound good?


Excuse me for the continuing, and thank you in advance for help!

 

[Veri]

Excuse me please for the continuation ... Whether the headphones with 62 ohms can work with SU9 without distortion and problems? This is AKG K712 (pro) with a mini-XLR male interface on them (see pic.), equipped with a 3-ring 3.5 mm interface cable. The manufacturer: Sensitivity (dB SPL/V @ 1 kHz) = 105. Maximum input power = 200 mW.

I would prefer to use the XLR output of the SU 9 for headphones

-I don't think you can even use the AKG K712 balanced without modding. I had to mod my Q701 to use a balanced cable. So no.
-XLR output impedance is ~370ohm from Amir's measurement. Way too high to directly drive headphones well.

You need an amp with XLR inputs and 1/4 inch output for your K712... something like the Geshelli Archel or the Topping A30 Pro.

 

[dpippel]

Excuse me please for the continuation ... Whether the headphones with 62 ohms can work with SU9 without distortion and problems? This is AKG K712 (pro) with a mini-XLR male interface on them (see pic.), equipped with a 3-ring 3.5 mm interface cable. The manufacturer: Sensitivity (dB SPL/V @ 1 kHz) = 105. Maximum input power = 200 mW.

I would prefer to use the XLR output of the SU 9 for headphones, because I use the RCA output to connect the SU 9 to an AV receiver. Could all of this be reliable and sound good?


Excuse me for the continuing, and thank you in advance for help!View attachment 126733

Like Veri said, you need a headphone amplifier connected to the SU-9 for your AKGs. Trying to drive them directly from the SU-9 is a no-no.

 

[Sergiy]

I bought this device couple monthes ago. Previously I had moustly bad experiance with "china" audio devices, but this time I read specs: good measurements + top sabre chip and reference design moustly. What could possibly go wrong? But I was dissapointned once again ((

Now I have Asus Xonar Essence (2xPCM1795 + 8xLMEXXXX(do not remember exactly) + 4xOPA627BP) and my old Asus simply declassify SU-9. Even my wife noticed big difference between them while cooking in another room. The sound is flat, static, no any desire to listen more and more.

I tested it on linux and windows (both bitperfect), tried to change all the settings, but no luck. I left this DAC to my mom to listen internet radio.

The only thing I am wondering right now: is something wrong with me or guys, who left a good feedback and praised this device, simply haven't heard how music could possibly sound.

P.S. I am a radio technician by education and believe that copper is copper and decent audio should not cost much, but unfortunately, that is not the case for "china" audio devices still.

 

[AdamG]

I bought this device couple monthes ago. Previously I had moustly bad experiance with "china" audio devices, but this time I red specs: good measurements + top sabre chip and reference design moustly. What could possibly go wrong? But I was dissapointned once again ((

Now I have Asus Xonar Essence (2xPCM1795 + 8xLMEXXXX(do not remember exactly) + 4xOPA627BP) and my old Asus simply declassify SU-9. Even my wife noticed big difference between them while cooking in another room. The sound is flat, static, no any deasire to listen more and more.

I tested it on linux and windows (both bitperfect), tried to change all the settings, but no luck. I left this DAC to my mom to listen internet radio.

The only thing I am wondering right now: is somethis wrong with me or guys, who left a good feedback and praised this device, simply haven't heard how music could possibly sound.

P.S. I am a radio technician by education and believe that copper is copper and decent audio should not cost much, but unfortunately, that is not the case for "china" audio devices still.

Welcome Aboard @Sergiy.

 

[aandres_gm]

Is anybody running a stack SU-9 -> A90? I'd love to hear some feedback. I'm thinking about either the SU-9 or the D30 Pro for my new stack, but I'm unsure on what to get, especially on the DAC side of things. I don't need MQA/Bluetooth, so they play no role in the decision. It's mostly a price/performance thing.

 

[AdamG]

Is anybody running a stack SU-9 -> A90? I'd love to hear some feedback. I'm thinking about either the SU-9 or the D30 Pro for my new stack, but I'm unsure on what to get, especially on the DAC side of things. I don't need MQA/Bluetooth, so they play no role in the decision. It's mostly a price/performance thing.

Welcome Aboard @aandres_gm.

 

[nessism]

Now I have Asus Xonar Essence (2xPCM1795 + 8xLMEXXXX(do not remember exactly) + 4xOPA627BP) and my old Asus simply declassify SU-9. Even my wife noticed big difference between them while cooking in another room. The sound is flat, static, no any desire to listen more and more.

.

I've got that same sound card (not the version II card which is worse) and use it as my benchmark. I've done countless back to back tests against Topping E30/L30, and/or using a Schiit Magni 3+ amp, and can't for the life of me tell any difference when using my HD6XXX headphones. I think that soundcard is very under rated. If your SU-9 sounds worse I suspect something is wrong with your setup though.

 

[Yaiba]

I bought this device couple monthes ago. Previously I had moustly bad experiance with "china" audio devices, but this time I read specs: good measurements + top sabre chip and reference design moustly. What could possibly go wrong? But I was dissapointned once again ((

Now I have Asus Xonar Essence (2xPCM1795 + 8xLMEXXXX(do not remember exactly) + 4xOPA627BP) and my old Asus simply declassify SU-9. Even my wife noticed big difference between them while cooking in another room. The sound is flat, static, no any desire to listen more and more.

I tested it on linux and windows (both bitperfect), tried to change all the settings, but no luck. I left this DAC to my mom to listen internet radio.

The only thing I am wondering right now: is something wrong with me or guys, who left a good feedback and praised this device, simply haven't heard how music could possibly sound.

P.S. I am a radio technician by education and believe that copper is copper and decent audio should not cost much, but unfortunately, that is not the case for "china" audio devices still.

I also have Asus Xonar Essense ST(Pci version)+H6 board. It's good for vocal song but I think it lack of bass and less detail when listen to song with complex instrument or noisy environment sound such as Pop/rock concert recorded. And driver is very bad for win10. When use ASIO mode it will have sound clipping when CPU spike from other process(I used it with I5-8600k@5GHz 6c/6t).

The key feature of SU-9 is Balanced dac. It very different when connect to monitor speaker via XLR connection. But for RCA, it should not sound worse than Xonar essense. It may not match to your system(such as impedance issue?) or your favorite song genre.

 

[possumtaters]

I’ve had my SU-9 for a month and it’s made a substantial improvement in my system. I originally had my Sonos Connect connected to my Outlaw RR2160 amp via RCA and Toslink, and would switch between the two, but never heard much of a difference between the Connect’s DAC and my amp’s internal DAC. With the SU-9, I have the RCA outputs connected to my Outlaw RR2160 amplifier and my SB2000 sub connected to the RR2160. From top to bottom the sound improved dramatically. Everything was more controlled, especially the bass, and all instruments sounded like they were separated and distinct, when hearing them through my Revel F36’s. One observation is using the Toslink (Lifatec) input from the Connect provides a much more enveloping experience vs the coax, at least with my setup. I A/B’d them both multiple times to be sure it wasn’t in my head. I have a Buckeye amp on order so I’m hoping to further improve my ecosystem using the balanced outputs for the mains and the RCA outputs for my subwoofer.

If you’re currently utilizing the DAC integrated to your amp, Connect, Node 2(I), or other, you should definitely try implementing an SU-9, or one of the other ASR higher rated DAC’s,

 

[JSmith]

Seems the issue with the M500 may be present also in the SU-9;

https://www.audiosciencereview.com/...nge-smsl-m500-high-3rd-harmonic.22710/page-10



JSmith

 

[nhs]

I bought the SU-9 because of one of @amirm best independent measurements but now I am listening to one of worst DAC measurements in stereo, weird

 

[liu]

The Dac is similar but it is the ess 9038 mobile version while the SU 9 has the 8 core pro version.

Well, even though SU-9 has the ES9038Pro, it only uses 2 channels of the total 8 channels. Unlike Matrix XSP which parallelizes multiple channels, The SMSL implementation is not very different from using an ES9038Q2M.
One can easily verify it with a multimeter (only channel 7 and 8 are connected to the I/V converter opamps.)

 

[SashaR]

Like Veri said, you need a headphone amplifier connected to the SU-9 for your AKGs. Trying to drive them directly from the SU-9 is a no-no.

Thank you again for your advice and help, dear dpippel!

 

[SashaR]

-I don't think you can even use the AKG K712 balanced without modding. I had to mod my Q701 to use a balanced cable. So no.
-XLR output impedance is ~370ohm from Amir's measurement. Way too high to directly drive headphones well.

You need an amp with XLR inputs and 1/4 inch output for your K712... something like the Geshelli Archel or the Topping A30 Pro.

Thank you for the explanations!..
Please, tell me how did you modify your headphones from 3 wires to 4? I saw a demonstration of this process on YouTube, but I can't decide to do it myself without fear of damaging the drivers.

The second question in connection with the conversion of 3-wire headphones to 4-wire: I often use K712 headphones with a phone. Forgive me for the completely unprofessional question, please: is it possible to have some kind of adapter from a 3-wire phone to a 4-wire headphone after such a modification of my headphones?

Excuse me for the abundance of questions - and for the lack of professionalism of them! Thank you!

 

[Veri]

Thank you for the explanations!..
Please, tell me how did you modify your headphones from 3 wires to 4? I saw a demonstration of this process on YouTube, but I can't decide to do it myself without fear of damaging the drivers.

The second question in connection with the conversion of 3-wire headphones to 4-wire: I often use K712 headphones with a phone. Forgive me for the completely unprofessional question, please: is it possible to have some kind of adapter from a 3-wire phone to a 4-wire headphone after such a modification of my headphones?

-Someone on a forum modded them for me so I'm not 100% sure. The balanced connection does not make anything sound different though
-I recommend to just get a good single ended amp. So you can keep using the same cables, also to connect to your phone. Why make things complicated?

 

[SOUNDSONIC]

My SU9 dissipates heat like a power amp after few hours of usage. Is this normal?

 

[Dingenus]

My SU9 dissipates heat like a power amp after few hours of usage. Is this normal?

Mine gets a little bit of lukewarm with a topping L30 on top. The L30 becomes clearly warmer.