JDS Labs Atom+ Stack Review

In this article, we review the JDS Labs Atom+ Stack, which is their Atom DAC & the Atom+ AMP. They respectively cost $109 USD and $99 USD.

Disclaimer: JDS Labs sent us the Atom+ stack for this review, free of charge. I only covered the customs fees & taxes. All thoughts and experiences with the product are naturally my own.

This review consists of 3 pages. The Atom+ DAC will be reviewed on page 1, the Atom+ AMP will be reviewed on page 2 and the stack performance of the two will be evaluated on page 3.  

JDS Labs

Many of you already have an acquaintance with JDS Labs because of the widely popular DACs & AMPs that they design. They are one of my favorite audio companies of all time. I have used many of their products in the past, even the old ones such as the JDS’s production of NwAvGuy’s O2 amplifier and Altoid can JDS CMoys. Those were the times! I can honestly say that I have never used anything “mediocre” from JDS. They always deliver in my experience. Today we will talk about the updated and upgraded Atom line.

But first, let’s talk a little bit about the company! Who are they, really?

Well, everything started with an audiophile’s pursuit of excellence. The story begins with John Seaber, the JDS in JDS Labs. John, who was not happy with the bass response of Sennheiser HD-280 Pro, designed a bass boost circuit and shared it with audio enthusiasts. In no time, John’s keen hands get overflown full of requests from other audio enthusiasts. Though JDS Labs was never planned to be a company, Co-Founder Nick joined in 2011, and the evolution that will make JDS Labs what it is today begins.

They are now this hugely popular killer company, which is trusted by the fans because of their honest and transparent attitude towards everything they do.

We have reviewed and awarded a lot of JDS Labs gear here on Headfonia over the years, check out their reviews here: Headfonia JDS Labs reviews

Now that you’re acquainted, let’s get to the good stuff.

JDS Labs Atom+ Desktop DAC

The dedicated web page can be found here. It costs $109 USD.

Frequency Response, 20Hz-20kHz +/- 0.12dB

SINAD @ 1kHz, 20-22.4kHz 112 dB 

THD+N, 20Hz-20kHz < 0.0004%

Noise (A-Weighted): -109 dBu

Dynamic Range (A-Weighted): > 120 dB

Maximum DAC Line-Output, 100K 2 VRMS

What’s New?

As you know, the Atom DAC used an AKM chip, and the terrible 82-hour fire that struck AKM changed many things in the industry. As an audiophile, it was extra upsetting to see a factory so important to the industry, damaged. However, life must go on and we should adapt to the circumstances. JDS’ skilled team did exactly that. According to JDS Labs, the DAC+ was born as a contingency plan and the brilliant team seems to have managed to achieve a significant improvement over the original Atom DAC without using an AKM chip. 

The improvements made are not limited to this. The Atom+ DAC now has an optical input and an instant input switch button on the front side. Additionally, Atom+ DAC now has standard support for UAC2 with UAC1 fallback. JDS states that the Atom+ DAC uses the same XMOS XU208 USB stage and dedicated AC power stage as the original. According to their detailed release post, only the AK4490EQ and the analog output have been replaced by an ES9018K2M and a carefully tuned, six opamp I/V converter. You can check the post for more detailed technical information about the Atom+ DAC.

Packaging & Accessories

JDS Labs’ approach towards the packaging is unique. They have this very simple yet practical packaging style. Their cardboard boxes remind me of DIY kits that I used to buy when I was younger. Long story short, the packaging is quite straightforward. I received two boxes; one for the DAC along with the accessories and one for the 16VAC power adapter that we’ve seen multiple times before with JDS Labs gear. I can’t see any significant difference in packaging compared to the original Atom. The 16VAC power adapter still feels really heavy and still occupies more than one power outlet socket.

As for the accessories, the Atom+ DAC comes with a brilliant, USB Type A to Type B cable, custom-made and finished with gold plated connectors and a TDK ferrite core that rejects noise and improves jitter performance. Apart from that, JDS also included a rocker power switch in the package to turn on or turn off the Atom+ DAC. Additionally, JDS includes a stamped inspection card in the package with every DAC & AMP purchase, stating that the unit has been inspected twice and assembled perfectly.

Design & Build Quality

Measuring 12.7 x 13.4 x 3.5 centimeters, the Atom+ DAC has a small footprint and it won’t take much space on your desk. It is also very lightweight at about 200 grams. Although it seems that there is no difference compared to the previous generation when looking at the device, I noticed the increased rigidity and better structural integrity as soon as I held it in my hands. The plastic seems thicker and stronger compared to the previous gen. I can’t see any assembly issues or case imperfections and that’s great. The input switch button feels tactile and smooth. The gold-plated RCA plugs and other ports feel solid, well made.

JDS also placed 4 anti-slip rubber feet under both of the units. They do their job well and they’re low profile. At this price point, it probably won’t get any better than this, build-wise. Well done.

As for the design, in my opinion, the objective line was too DIY, even for me. The Atom line, however, looks simple, and elegant at the same time. The white light-ring design looks gorgeous, especially at night. The dimness of the light ring is very well-thought and it does strain one’s eyes. Let’s move on to the layout. On the front, we have an input switch button that we can use to switch between USB and optical inputs. On the rear side of the DAC, we see RCA outputs, a USB input, and a Toslink input as well as a barrel-type power socket. The layout is clean and easy to learn.

Features

When you factor in the AKM factory fire and the coronavirus pandemic, JDS Labs tops the list of limited companies that can dare to offer better performance, an extra input, and better build quality than the older generation for just a $10 price increase. Let that sink in for a second.

As an audiophile first and a reviewer second, I thank JDS Labs for their consistency. Now that I got it off my chest, we can move on to the features. 

JDS Labs Atom+ DAC features upgradeable firmware via XMOS’ USB controller, XU208. JDS offers several different firmware options for you to choose from and upgrading is quite easy. JDS also offers custom firmware if you intend to use the DAC with your Sony PS4, PS5, or Nintendo Switch. There is even a custom, experimental firmware that mimics the sound of the tube-based device. You can try that from here if you feel like experimenting on this fine day.

Additionally, the Atom+ DAC does not feature an onboard power switch, instead, it enters standby after 15 minutes of inactivity, powering down its light ring and D/A circuitry, and wakes up when you need it, within milliseconds. If you want full control and no autonomy, JDS also got you covered because now the DAC ships with an external power switch. 

As for the supported sample rates, the DAC can decode 16/44.1kHz thru 32/384kHz PCM, DSD64-DSD128 via USB, and 16/44.1k thru 24/192k PCM via Toslink. In my experience, I had to update the device to the latest firmware v1.8.9 to enable DSD playback so if you have any issues with that, just check the firmware version.

DAC Performance

In this section, I will try to describe the DAC’s signature, without the Atom+ Amp. For this test, I am pairing the DAC directly with my active reference monitors. I’ll be A/B’ing between the Atom and Atom+ DACs.

Let’s start with the signature. Just like the previous-gen, Atom sounds clean and uncolored. Nothing has changed here, signature-wise. It feels just as clean and clear without any dips or peaks. Tonality seems to be the same, the natural attack and decay of the instruments feel organic and the transients feel snappy with good resolution. Instruments have plenty of air between them, are positioned well and the stage does not feel crowded or congested.

The bass is just as powerful and thick as it was before. It has the means and the tools to deliver a strong bass response. The harmonics are felt without any roll-off. The low end has good authority but stays within the limits without any bleeding. The midrange is defined and resolving, vocals are clean and articulate. It is very pleasing to listen to Jazz divas of the 90s with this little wonder box. The upper mids have the same excellent energy while staying in their dedicated ground and do not shine more than they need to. Treble extension is just as good as the previous gen, maybe even slightly better in the top octave. Technical-wise, the Atom+ feels a tad more linear, slightly more detailed, especially in the treble region. This is a highly resolving DAC that costs a little over a hundred bucks and it is a serious contender at this price range.

vs. Topping D10 Balanced

I received Topping D10B around a week ago and I’ve been listening to it quite often. It sells for $139 USD and it is a DAC-only device. It utilizes the ESS Technology ES9038Q2M premium-tier DAC chip. It has TRS balanced out and I hooked it up to my reference monitors to compare it with the Atom+ DAC. First and foremost, the D10B sounds slightly more detailed compared to the Atom+. Micro-detail retrieval feels slightly better as well, D10B feels more revealing, especially with congested tracks with multiple instruments. The Atom+ DAC offers a slighly rounder bass response while D10B aims for a more linear, faster reproduction. Both of the devices are really good and won’t let you down. You can’t go wrong with either.

The review continues on Page Two, after the click HERE or by using the jump below.

Page 2: JDS Labs, JDS Labs Atom+ Desktop Amp, What’s New?, Packaging & Accessories, Design & Build Quality, Power & Technology, Controls, Warranty, Amp Performance

Page 3: JDS Labs Atom+ DAC & AMP Stack Performance, Pairings, Last Words