S.M.S.L SU-8S

Aibo

Head-Fier
Strong Midrange Performer
Pros: Dynamic presentation
Quick and precise sound
Great detail retrieval
Cons: With some pairing care and at this price, not much really
SMSL is becoming well known for the affordable DACs with great value and SU-8s tries not to be an exception. The asking price of 349 USD is located in the middle of the SMSL DAC offering, just a small step below their previously released SU-9. Even though the price is shaved by one hundred dollars, SU-8s still brings many interesting features. Hopefully, these features will lead to good performance, but that’s what we aim to determine today, so let us begin.

Build and Connectivity​

SMSL SU-8s looked from the outside resembles a lot to its older and slightly more expensive sibling SU-9. It’s completely made of aluminum, uses a color LCD in the front, the same volume knob, and the remote. On the back, things again look very familiar with USB, optical, and coaxial digital inputs. Bluetooth 5.0 connectivity is on-board again too, supporting aptX, aptX HD, SBC, and AAC formats. When it comes to outputs, we can choose between single-ended RCA or balanced XLR ones.

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Features and Tech​

Looking at the spec sheet we finally find some differences. Namely, SU-8s uses ESS ES9068AS DAC chip instead of the ES9038PRO found in SU-9. That doesn’t affect its great format support that includes PCM all the way up to 768 kHz, DSD up to 512, and even a controversial MQA compression unfolding is fully hardware supported (for the ones that are not familiar with it, MQA is basically a lossy compression aimed at reducing the hi-res file size. All manufacturers have to pay royalties to use it and it doesn’t sound as good as uncompressed hi-res files. Tidal streaming service is the biggest proponent of such compression).

Inside the menu, you can choose one of three PCM filters on offer, then choose one of different tone colors (standard, rich 1, 2, 3, tube 1, 2, 3, crystal 1, 2, 3), and even adjust the level of DPLL level of de-jitter. Since there are too many variations that will slightly affect the sound signature, I will not go through all of them. I personally preferred PCM slow minimum filter, sound color Rich 1, and DPLL at its minimum level, but you should definitely play for yourself and find the ones that suit your taste and the rest of your system best.

To add the last touch, SMSL lets you choose the display brightness and enable the auto-off function. You’ll even be allowed to choose after how many seconds of inactivity the display shall turn off. Small touches like these can make or break the experience of using a product daily when the novelty wears off, and for this kind of attention to detail, SMSL deserves the highest praises.

Sound​

But how does the SU-8s actually sounds is the most important question I suppose. To put it shortly, it sounds very good considering its price. A trained ear will quickly recognize that quick and sharp Sabre sound signature. Highs are bright and airy, mid-range is clean and informative, emphasizing crisp edges and transients. That leaves us with the bassline that’s quick and nimble, but somewhat restrained with the default linear filter, but opt for a slow minimum or minimum phase one and it starts sounding weightier, softening some transients in the process. The same is true if you opt for some of the Rich or Tube sound color filters. All of this is important since you can actually tilt the overall sound signature from fast and analytical by default to a somewhat fuller and softer presentation if you wish to do so.

Moving away from the tonality itself, SU-8s has a lot to show when it comes to micro-dynamics. Edges are energetic and transients are quick, making for both revealing and exciting presentation. When it comes to the soundstage, SMSL SU-8s renders a somewhat forward and upfront sound scene, meaning there is not much depth to talk about. That said, the soundstage is sufficiently wide, tall, and offers plenty of air. Instruments are well separated and masterfully etched in their own place.

All in all, SMSL SU-8s is a capable sounding DAC without any doubt, but the real test is to face it against some closest competition and access its true worth.

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Comparisons​

Topping D30 pro is a direct competitor when it comes to pricing and market positioning. Topping’s contender provides a somewhat warmer bassline and the midbass section, with a more laid-back presentation. It presents edges in a softer fashion, but ultimately reveals a respectable amount of the inner tone texture. SU-8s on the other hand has more upfront presentation, with more energetic edges, quicker and crisper transients. In the upper registers, the D30 pro has a bit grainier and more textured sound to it, while SU-8s sounds cleaner but with more glare and brightness. Choosing between these two finally proved very difficult and depending on your preferences and the rest of the system each one can end up as the preferred one.

To sum it up really quick, I suppose that all of you looking for dynamics, clarity, and excitement before anything else might prefer SU-8s, while the ones appreciating more laid-back, fuller, and softer presentation could lean towards D30 pro more.

SMSL SU-9 has been mentioned throughout this whole review due to the striking resemblance of these models. It carries a 100 USD higher price tag and it comes with the best DAC chip that Sabre produces. That said, the differences in sound fidelity are not that big. Now have in mind that I didn’t have a chance to compare these two directly, but given that I’ve tested SU-9 recently, I’ll give my best shot to make this comparison as I’m sure it will interest most readers. SU-9 offers a somewhat punchier sound if my memory serves well, and that is especially true for the bass region. I remember it hitting with more intent and force. The same is true for the transients that felt somewhat faster on SU-9. That said, I feel that SU-8s is somewhat airer sounding and that its flatter bassline is probably more neutral. To be perfectly honest here, I would be much more comfortable making any definite statements if I could compare them head to head. But either way, both carry a similar, lively, sound signature and you can’t go wrong either way. In my opinion, SU-8s is probably a better value among the two, but SU-9 is still a great offer, especially if you value that extra punch and oomph in the bass region.

Conclusion​

SMSL SU-8s is yet another product coming from the SMSL that is quite easy to recommend. Its upfront and somewhat snappy sound signature mean you have to be on board with its character and take a little bit of care not to pair it with similarly zesty-sounding gear because you probably wouldn’t want to emphasize it even more. On the other hand, it’s well built, feature-rich, lively-sounding DAC that has no real faults given its relatively modest price tag. In other words, this is an extremely great value product that’s quite easy to recommend.

. . .

You can read all of my reviews at https://iiwireviews.com/

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corgifall

500+ Head-Fier
Pros: Great overall sound quality, Bluetooth, fantastic looks, customizable options via UI.
Cons: A hair bright due to Sabre "glare". Slightly smaller than SH/SU-9 so stacking it with those devices looks weird.
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I recently reviewed the SU-9 from S.M.S.L and I absolutely loved it and it continues to be my main DAC for desktop use. It was the first ESS DAC I used that was super smooth sounding yet extremely detailed. It was definitely a big win in my books and came in just under $440 at the time it launched. Now we have a new DAC from S.M.S.L that comes in a little less at $359.99. It’s using the newest SABRE ES9068AS DAC(non pro) from ESS and has a few upgrades to the UI as well.

Thanks to Shenzhenaudio for hooking me up with a review unit early. While I always appreciate stuff being sent in to test and review, It never affects the rating of my review.

The SU-8S can be picked up from Shenzhenaudio here: https://shenzhenaudio.com/collections/all/products/smsl-su-8s-mqa-full-headphone-dac-es9068as-dac-xmos-dsd512-pcm768khz-32bit-bluetooth-5-0-uat-aptx-hd-uat-balanced-decoder


Gear used​

S.M.S.L. SU-9, S.M.S.L. SH-8S/SP400, iFi micro iDSD Signature, Ikko OH10, DUNU EST 112/ZEN, THIEAUDIO Clairvoyance and Focal radiance.

Looks and Feel

It looks like all the more recent SMSl gear and comes in a nice black matte casing. There is a tempered glass over the lcd display which gives it a nice look quality wise. It’s still not very heavy and can move around if bumped and it’s still somewhat hard to get to sit aligned if used in a stack when stiff cables are in use.
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*side note*
While both the SH/SU-8S look the same size wise as the SH/SU-9, The 8S devices are just a hair smaller in width and length, ll the devices are the same height however.

Accessories and unboxing​

It comes in a super simple cardboard box. It’s well protected in a bag inside of foam. We get a fairly meh USB type B to A cable(same cable that comes with the SU-9), a power cable and a remote. I like the simple S.M.S.L remote and it works with both the SU-8s/9 and the SH-8s/9/sp400 as well as the DA-9 from S.M.S.L. The QC pass card and the user manual is also included.
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UI​

I normally don’t go into super detail but I’ll include pics of the UI below. The biggest changes vs the SU-9 are the inverted sound output options, option to use the processor vs xmos chip for SPDIF, and finally the option to turn off the display after a certain amount of time. While I like the display on personally, I would prefer the option to turn the display off in a living room.
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MQA​

It works... It still has a hard time “latching” to the stream just like the SU-9 when you pick a random part of the song, which can make the song have a second or two of “compressed” sounding playback till it shows MQA again. I still don’t like MQA personally but I still like to check and make sure the feature work.

Bluetooth​

The bluetooth works really well and while I normally don’t use the feature in my desktop setup, I still had no cutout issues when paired to my PC, iPhone 12 pro or iPad air.

Sound(overall)​

These final impressions were done off the SU-8S outputting to both the S.M.S.L SH-8S and SP400. This will be what the S.M.S.L SU-8S sounded like with the headphones I used. Things like headphone pairings or using different external amps will produce different results and impressions vs what my ears hear on my specific gear.

Lows are well maintained and sounded fairly good off both the SH-8s and SP400. There is a nice impact and thump. It can still come off a bit neutral/lean vs something like its bigger brother the SU-9. The mids have a nice presentation with fairly accurate sounding instruments and vocals. Where this and the SU-9 start to drift apart is the treble and soundstage. The SABRE “glare” is definitely more present and while this gives a nice impression of detail on first listen, it can sound a little metallic and artificial over time. I used to love the ESS SABRE sound flavor in my early audio reviewing days. I tend to enjoy detailed but warmer sources now that I’ve been doing this for a bit.

Imaging/Soundstage​

I think soundstage and imaging are more reliant on amps and headphones. That being said a DAC can add or detract a little bit of staging and imaging. In the case of the two amps and the two headphones I use for width and depth, the SU-8S gets a pass. Width is about average and depth is no different. A “closer to you head” soundstage with both amps I used but I don’t find it to be a real issue. Imaging was phenomenal but I expect that with modern $200+ DACs.

Inputs and outputs​

We get Bluetooth, USB-B, optical and coaxial for inputs. We have a balanced XLR out and RCA out as well. Fairly standard and everything is nicely packed into the thinner casing.
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Personal grips with the S.M.S.L?​

I usually have something to complain about but the only things that were missing from the SU-9 user interface were fixed with this new unit. OH! These units still come with only three feet but they actually include 4 extra feet in the box so you can add the feet to make the unit more stable.

DAC comparison​

S.M.S.L SU-9​

Both have a fairly different sound presentation even though they both use ESS DACs. The SU-8S has a higher focus on mids and treble and the SU-9 has better detail retrieval yet doesn’t come off as bright and goes for a relaxed sound signature. The staging was wider and deeper on the SU-9 with my use of the same amps between both DACs. Keep in mind that this is all done via switching gear as quickly as possible. While I did manage to get a really fast speed of switching DACs, this could all be placebo. I did manage to blind pick the SU-9 out over the SU-8S(thanks to the girlfriend for dealing with my weird experiments). So take this comparison as you will.

Amps pairings​

S.M.S.L SH-8S​

This is the amp that is meant to “stack” with the SU-8s. The pairing produces a fairly good sound presentation. The “stack” gives a fairly accurate sound without sounding super lean or boring. There is a little more noticeable top end energy thanks to the noticeable SABRE “glare” but for most people I think this will give off a super accurate sounding combo that really impresses.
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S.M.S.L SP400​

The SP400 is my favorite “Super detailed without being cold/clinical” amp. I never really liked the standard THX sound of amps and this was the first to carry the tag and also blow my mind with my headphones. The SP400 sounds awesome with the SU-8s and it really brings the ES9068AS to life. It also comes in a little brighter due to the DAC being used in the SU-8S. Staging was a bit better and the low end had very good energy with a nice detailed mids and treble.
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Overall thoughts​

Should you pick the SU-8S over the SU-9? Well if you think you want a DAC that pushes for a slightly sharper treble then this is the DAC to get. If you want a somewhat warmer sounding DAC then something like the SU-9 will be a better option. I think both the SU-8S and SU-9 are winners and I have no issues recommending the SU-8S. I still prefer the SU-9 over the SU-8S but this is a personal sound preference. I was happy to see the SU-8 get its own sequel device as that was my daily DAC till the SU-9 launched. Good job to the S.M.S.L team and thanks for reading!
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