SMSL D-6 DAC Review

[amirm]

This is a review and detailed measurements of the SMSL D-6 balanced stereo DAC with Bluetooth. It was sent to be by Shenzhenaudio and costs US $169.99.

I like the compact enclosure even though there is a built-in power supply and balanced outputs. Included volume control lets you bypass a pre-amp and driver a power amplifier directly.

SMSL is joining others in using compact TRS for balanced output. Along those lines, USB input is also the diminutive USB-C connector.

I found the navigation of settings or even changing inputs to be somewhat confusing. This is compounded with selections not rolling back to the beginning. So you wind up pressing buttons while seemingly nothing happens because you are at the end of list of selections.

AKM AK4493 DAC chip powers the unit.

SMSL D-6 Measurements
Let's start with RCA output:

Distortion is well below threshold of audibility so noise sets SINAD. Switching to balanced output improves the situation still:

For a budget DAC, this is excellent response, ranking above average in that category alone: (highlighted in yello)

Dynamic range is situated the same:

Multitone test shows off the low distortion:

Linearity is excellent to 20 bits limit of measurement:

Great to see jitter being extremely low for all three inputs and not just USB:

IMD test shows off the low distortion:

We have the usual filter settings from AKM:

None are sadly very sharp so we see the effect in THD+N vs frequency which uses a wideband measurement spectrum of 90 kHz:

We can see why if we perform an FFT:

Fortunately not an audible artifact.

Conclusions
SMSL delivers an excellently engineered DAC with my favorite features of included power supply and balanced output at very budget friendly price. You don't get state of the art performance but come close while saving fair bit of money. The D-6 is also stylish with its compact and slim size.

I am happy to add SMSL D-6 to my recommended list.

-----------
As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

 

[juliangst]

Wanted to get the DO100 but price increased from 215€ to 240€ on amazon. I'm probably gonna get the D-6 now

 

[DamianW]

Does the volume control work with DSD as well as PCM?

 

[OldManMatt]

If these smaller companies are able to get this kinda performance out of these chip dacs for this kinda price why can't the larger companies with big financial backing get close or equal these dynamic and low distortion numbers in their mid and upper priced AVR's? Or any of their gear..is it a money thing, not cost effective?

 

[juliangst]

If these smaller companies are able to get this kinda performance out of these chip dacs for this kinda price why can't the larger companies with big financial backing get close or equal these dynamic and low distortion numbers in their mid and upper priced AVR's? Or any of their gear..is it a money thing, not cost effective?

They simply don't care because their customers don't care either. People like us who care about low distortion, jitter or high dynamic range are the minority

 

[OldManMatt]

They simply don't care because their customers don't care either. People like us who care abut low distortion, jitter or high dynamic range are the minority

Its a shame. I can personally say that some of the reviews that come through here I find rather upsetting. Sorry for going off on a side note, I don't want to detract from SMSL's moment of glory here

 

[RandomEar]

I think we need a new way to dislpay the ranking. Even at full size, the device names are getting hard to read

I vote for a histogram!

 

[Lambda]

I which it would be DC powered by USB(C) only

Is the balanced output symmetrical "fully balanced" (both lines driven) or only impedance balanced?

 

[amirm]

I vote for a histogram!

Interesting suggestion. In such a graph, you wouldn't be able to see and identify the rest of the products. You are OK with that?

 

[Tks]

@RandomEar Yeah a new color for devices above 115, and devices above 120.

If these smaller companies are able to get this kinda performance out of these chip dacs for this kinda price why can't the larger companies with big financial backing get close or equal these dynamic and low distortion numbers in their mid and upper priced AVR's? Or any of their gear..is it a money thing, not cost effective?

Same reason car companies are diehards for old as heck chip nodes. It's gotten so bad that TSMC has said they're not going to be making older chips anymore for companies, and companies will have to move on to using 28nm at worst (keep in mind, you iPhone is running on 5nm chips by comparison, 28nm is basically a decade old now, and shithole car companies with their laggy ass car OS's still want to use chips as old as they can possibly source).

I'm too lazy to check out Mouser, but I think the CL and TI chips for example are to be had for cheaper than AKM and certainly cheaper than ESS. But I think it simply has to do with not having to hire a whole new team to learn how to implement things properly from a totally different manufacturer (and possibly because they get great deals from other manufacturers).

As for why companies don't do this in the AVR space, that's because most of the budget goes elsewhere (consumer DACs get absolutely obliterated by the DSP capabilities, and the I/O options AVR's come with, it's so bad in fact, whenever I see a DAC that has dual TOSLINK inputs, I call that a miracle, and then it gets quickly dashed because it's on a multi kilobuck device which I don't care about). AVR makers also don't take their customers to be a userbase that cares enough to educate themselves beyond brand hype and market penetration (and beyond subjective reviews online). And the last reason they don't change if they even know what a SINAD number even is - is because they don't think there's an audible difference worth considering. They're all in the same AVR industry, and all probably get pooled into a handful of manufacturers providing parts for them at a favorable price. Desktop DACs on the other hand, seemingly will NEVER have things like HDMI audio routing support, or any of the multitude of licensed tech AVRs must support.

As much as I take car tech progress to be a joke, I still have to understand that you're not going to be able to get the price Apple gets for their chips. In 2020, there were I think less than 15 million car sales in America. That's for the entire industry... Apple on the other hand, sells more than that many units per quarter.

 

[Matias]

Interesting suggestion. In such a graph, you wouldn't be able to see and identify the rest of the products. You are OK with that?

If there is a link to a full list elsewhere, then sure!

 

[WhyNotHad]

It's really great. However, this product has a clicking issue at the beginning when playing music files on the Tidal. I don't know why, but I hope it will be updated soon.

Good job bro

 

[Matias]

Good to see new products using AKM chips again!

 

[mhardy6647]

I think we need a new way to dislpay the ranking. Even at full size, the device names are getting hard to read

I vote for a histogram!

Time to go logarithmic, perhaps?

 

[rob755]

Greetings Amir, I was wondering if you heard clicks/pops and if so what you have to say about them? I have one and really like it. The synergy is just great in my system as it is these days. Thanks.

 

[amirm]

Greetings Amir, I was wondering if you heard clicks/pops and if so what you have to say about them? I have one and really like it. The synergy is just great in my system as it is these days. Thanks.

I have not but will test for it when I get a chance.

 

[Doodski]

Time to go logarithmic, perhaps?

I think the compatibility of cel tels and desktop displays denotes some sort of limitations in graphing this out and keeping everybody happy campers while viewing all the information.

 

[rob755]

I have not but will test for it when I get a chance.

Thanks for getting back. Hope you are well.

 

[DonR]

I think we need a new way to dislpay the ranking. Even at full size, the device names are getting hard to read

I vote for a histogram!

I agree. Maybe only show the relevant colour or say 25 on either side. As for the DAC itself... meh... another DAC that measures excellent under $200. ho hum. Although... the feature set seems to be above average here at this price point.

 

[mhardy6647]

Must be some straightforward way to nest the data(?).
You know, bucket into groups of 5 or 10 or whatever (histogram), but hovering over (or clicking on) a bucket pops up the individual contents of that bucket.