JDS Labs Atom DAC
Atom DAC is built to pair with the enormously popular JDS Labs Atom Amp, adopting our latest XMOS based USB Audio Class 2 input stage with MEMS oscillator and support for future firmware updates. Atom DAC is powered by a dedicated 15VAC transformer, ensuring consistency of noise performance when paired with other transformer isolated amplifiers like Atom Amp. A subtle light ring glows when in use. Atom DAC ships today for only $99 USD.
Firmware and Operation
Current versions of Android and iOS have also been tested successfully. Please note that UAC2 support varies with mobile devices.
Atom DAC achieves <0.00045% THD+N @ 1k A-Weighted, or SINAD >106 dB*, exceeding the capabilities of our dScope Series III and Audio Precision APx515:
A 24MHz SiTime MEMS oscillator outperforms OL DAC’s USB jitter by a wide margin of 8dB @ 12kHz.
|Frequency Response 10Hz-20kHz (192k)||+/- 0.15dB|
|THD+N 20Hz-20kHz||< 0.0008%|
|IMD CCIF 19/20 kHz -6.03 dBFS||0.00013%|
|IMD SMPTE -6.03 dBFS||0.0017%|
|Noise (A-Weighted)||-109 dBu|
|Dynamic Range (A-Weighted)||117 dB|
|Linearity Error -90 dBFS||-0.06 dB|
|Crosstalk -10 dBFS 100K RCA||-104 dB|
|USB Jitter Components 12kHz||-124 dB|
|Maximum DAC Line-Output, 100K||2.0 VRMS|
*There has been hyper focus on measurements in recent years, in a race towards Bigger and Better numbers. JDS Labs has benefited due to our longterm focus on honest performance. If the agreed threshold for “transparency” was 0.005% THD+N nearly a decade ago (only 86dB SINAD!), take a moment to consider that SINAD of 96dB is 10x cleaner , and 106dB is 100x cleaner than the previously agreed point of transparency. Whether you’re an objectivist or subjectivist, or somewhere in-between, please remember that our goal is to help you enjoy listening to the world’s best headphones. Audio performance is exceptional today.
EDIT June 11, 2020: SINAD of 110dB has been confirmed on an APx555 by Amir @ ASR. Thank you!
|OL DAC – USB Edition||Atom DAC|
|Power Button||None||Auto Standby|
|USB Controller||SA9023||XMOS XU208|
|Oscillator||CMOS Oscillator||SiTime MEMS|
Secret Release Dates
I know thousands of you have been begging for Atom DAC since the day we released the award winning Atom Amp. We were overwhelmed by Atom’s success and a matching DAC was not on our 2018 roadmap. Atom is a wildly successful experiment which required a flurry of concept refinement during a period of 90% growth. Early feature considerations were ruled out, as we recognized that the majority of customers adopting Atom wanted a competent, affordable USB DAC.
Two alternative Atom DAC featuresets were prototyped concurrently in 2019. The more complex featureset worked, but would have pushed cost higher unless we lengthened development time to omit the 15VAC transformer and revert to a USB powered design. We committed to proper AC mains isolation in our last generation of DAC designs, and our customers have been pleased with the consistency of AC powered DACs since then. Keep in mind that the “free” 15VAC adapter bundled with Atom DAC retails for $16.99 USD, so a healthy chunk of Atom DAC’s cost is our commitment to the benefits of an AC transformer.
Atom DAC was originally scheduled for release in November 2019. I began hinting that Atom DAC was close and would be released in 2019. Firmware was complete, enclosures had arrived at JDS Labs, numbers looked good, FCC/CE testing passed, and listening impressions had gone well for those of us at JDS Labs and for random customers (thank you to all who evaluated!). What could go wrong?!
Just days before we initiated PCB fabrication, I visually compared measurements of Atom DAC to the older JDS Labs OL DAC. Uh oh. I had ignored small 60Hz*n spikes, masked by numerically excellent A-weighted testing. We normally run both A-weighted and non-weighted measurements. I had skipped non-weighted testing on the fourth prototype after seeing strong performance of the first three builds. Knowing the cause and solution, I cancelled the Nov 2019 production to run to build two more boards. Atom DAC v6 finally passed all testing and was released for PCB manufacturing on Dec 23, 2019.
When all materials are available, PCB production runs can be pulled together in under two weeks. Atom DAC relies on some relatively obscure parts, with lead times of 8-14 weeks. I conservatively withheld ordering three components in bulk until the last minute, due to their direct impact on radiated emissions. These parts can be substituted or customized to balance performance and emissions compliance, and must not be changed once a design is locked in.
Electronics are globally sourced. As the ship date neared for the critical parts, our US distributor issued a notice of extended lead times due to COVID-19. Likewise, lead time of AC transformers doubled. Just as we were ready to announce Atom DAC, the pandemic forced the majority of our staff to work from home. Fortunately, we had not announced a firm date or taken preorders, so the only harm done was to our patience.
Thank you all for waiting. Atom DAC is here, and we hope you enjoy!
Atom DAC is In Stock exclusively at jdslabs.com today.
- Audio Science Review – JDS Labs Atom DAC Review
55 thoughts to “JDS Labs Atom DAC — Official Release & Benchmarks”
This is great news! I will be ordering an Atom DAC soon to pair with my Atom Amp. Thanks guys!
Will there be a version with optical/coaxial in? Or maybe another usb input? I think it would be nice to have two digital inputs.
Hi! It looks awesome, congrats! Just wanted to know, does automatic standby kick in after 15 minutes of inactivity from the source, or from the output? Maybe this question doesn’t make sense, but if I turn the amp off, will that suffice, or do I need to make sure my source isn’t transmitting sound via the USB? Thanks.
Standby kicks in after inactivity from the USB host/source.
Whoooooooooooa! Finally! Now I can sell my rme adi dac 2 😀
Uhhh what? Theyre in completely difference classes of performance. Im not sure the Atom lineup is bad, I actually love it, its just the RME is significantly better in every way. In terms of audible differences to human hearing, probably wont notice between Atom and RME though, so you do you haha.
I meant to say Im not ‘SAYING’ the Atom lineup is bad, not that Im not ‘sure’.
awww. If I knew about this DAC release I would have held off ordering another DAC and got this to go with my atom. Oh well, nice release guys!
Will there be a version with Toslink input?
@Caleb – I wanted to see TOSLINK support in this design, and chose not to copy and paste this area from our previous work after finding a better way. Your feedback will be forwarded along!
Plz Make atom dac with spdif input optical and coaxial version.
Congrats on the DAC, John.
Software > Hardware
Is the font on the front different from the one used on the Atom Amp?
Same font; we will update spacing on Atom Amp in the next batch to match.
Do you have an ETA on when the batch will be available? Would love to buy a matching stack, but prefer to have the fonts match as well.
BTW, congratulations on bring this DAC to market given all the turmoil.
@ANON – Fall 2020. Thank you!
If I buy one right now (August), will I receive one with the fixed font? Thanks.
@Nel – Atom Amps with the new font have arrived and will begin shipping this afternoon!
Did you guys by chance send this amazing product over to Amir at ASR for testing?
Yes, Amir has a sample Atom DAC.
Thanks! Link has been added to the article above.
“106dB is 100x cleaner than the previously agreed point of transparency. ”
woah! thx for giving us this perspective. 🙂
If it’s performance is similar to Khadas Tone Board then this is perfect DAC!
@Guetta: Totally different! https://blog.jdslabs.com/2018/11/jds-labs-atom-amp-official-release-benchmarks/#comment-22949
Hmm as I can see that KTB it is measuring perfect on ASR review. I have the device in combo with my JDS Labs Atom AMP and no single issue. Maybe because I am using it just with an AMP? No active preamp or external system
Can’t wait to see ASR results of JDS Atom DAC. It would stack nicely with my Atom AMP. 😀
With a head-amp it’s no problem 😉
Have you had a chance to test this DAC with PS4 Pro using its USB output?
Just thinking ahead as no one is sure whether the PS5 will have an optical out. In case it only supports audio over USB, I will need an extra DAC with USB input only.
@Boris: PS4 only supports UAC1, so no UAC2 can connect. We can provide custom UAC1 firmware upon request, but there is a caveat: Forcing UAC1 disables the DFU device. In other words, it’s a one way change.
There is a UAC2-to-UAC1 fallback option in the XMOS codebase. I have not tested this, but will do so if there is sufficient interest.
Are internal weights needed for the Atom amp to stay flush when stacked? You mention the weights aren’t necessary when used with the JDS Labs Stack RCA cables, but in the photo it looks like the pull of the cables is causing the front of the Atom amp to pop up.
@Matt: Atom DAC and Atom Amp are designed with a slight front uptilt; they do not rest at 0 degrees. This is why the front appears to be lifted, and has no relationship to the device weight. The default build is just fine!
would love to see a combo device similar to the element.
it would bring the total cost down, as only one ac adaptor, one pcb and one case areneed.
It also avoids the possibility of ground loops as the dac and amp would have the same ground.
Thanks for the feedback!
Use of AC transformers also avoids ground loops; this is the primary reason Atom DAC was designed to require an AC transformer. You are correct that an amp+DAC is more cost efficient; it is slightly more challenging to design both onto one board while maintaining incredible performance.
On that note, Atom DAC and Element II share the same DAC circuitry, yet, SINAD of Atom DAC is slightly higher from Atom DAC because of fewer components involved impacting the noise floor. At today’s high performance levels, even small changes to firmware like LED intensity can degrade benchmarks. With this in mind, we need to ask ourselves what is most important to improve the listening experience. I’m not sure pushing benchmarks higher is the answer.
Oh I believe the performance of JDS products (atom, element, etc) is good enough for 99% of the people. To me they’re all perfect. I would rather see manufacturers like you spending time on the user experience side.
For instance, not having two adapters make the desktop wires less cluttered (you know how messy year 2020’s cable management is. turning it to 1 device eliminate 3 wires, 2 rca and one power). It also allows the user to turn off both devices with one single push button (currently it’s a mess — amp has a button on the front, and the dac’s button is on extension cable).
Also very importantly, I’d like to see a -10 or -15 db gain on HP amps, which is not only useful for IEM users, but also solves the channel imbalance issues for people like me who listen with low volume (so no need to turn their pot before 10 o’clock).
I don’t mind the final product a little bit bigger, if you need extra space for isolation.
Great thoughts to consider. So basically, you would like to see an affordable amp+DAC with extra attenuation at the frontend?
Effective late May 2020, all Atom Amps are now built with hand matched volume pots. Channel balance is better than ever.
> you would like to see an affordable amp+DAC with extra attenuation at the frontend?
exactly. Massdrop THX AAA has -9db attenuation. RME ADI-2 DAC has a IEM port, at 0.55V ( -11.2db gain compared to 2V Line out). I assume with just a few extra resistors, JDS amps could have the same feature.
> Effective late May 2020, all Atom Amps are now built with hand matched volume pots. Channel balance is better than ever.
We have email conversation on this last year (you were also inviting me for testing at planning stage but probably forgot about it later on when working on the product… ). Nice to hear that this has been improved significantly.
I still believe a minus gain is useful. Making the pot perform well at low volume would cost manufacturer significantly more. With extra -10 ~ -15db gain available you may be able to achieve better result, while reduce the cost of the customized pot.
in addition to channel balance improvement, minus gain in certain situations can also reduce the noise (for instance, when most of the noise come from the DAC rather than the amp side). Useful for IEM users.
John, what would happen if I use a barrel jack splitter to run both an Atom Amp and an Atom DAC off same the 16V 1000 mA transformer? i) this would be fine? ii) some sort of ground loop? iii) immaterially impacted performance? iv) very poor performance? v) good performance but less power available?
@Paul: This will result in ground loop, as you would bypass AC transformer isolation between the two devices. The separate linear regulators driven by a single AC outlet would create ground loop, likely audible. Strongly discouraged.
Second question: why the 15 minute standby timer? If the DAC is on whenever the USB uplink is available, couldn’t you make the timer ~5 seconds and the amp will be on essentially any time the computer or streamer is on and turn off pretty much immediately upon PC shutdown?
@Paul – Soft muting, or soft powerdowns in any DAC implementation are likely to produce a small transient when unmuting. This is difficult to avoid without a physical relay. In other words, a 15 minute delay reduces the occurrence of potentially audible transients.
Hey John, would that explain the audible pop that occurs when powering on the unit or when the unit wakes up from sleep mode? Is this normal behaviour and nothing to be afraid of?
Correct, this small transient is normal and safe. Startup transients are common to many entry-level DACs. The wakeup transient is rather small in most instances. We use a muting relay in EL DAC II and in all JDS Labs amplifiers.
It’s good practice with any system to power up DAC/EQs/preamps first, and apply power to the final amplifier in the chain last. This will bypass any unexpected noises from equipment earlier in the chain.
Is the USB Type B connection necessary if i have a 3.5mm running into the atom amp from my PC?
Loving my stack and it’s nice to complete the JDS Labs family. https://imgur.com/bn0GKaM
Coming back to the question from Matt about the pop on start up and the response from John allaying any concerns about this trainsient effect. I also had a seperate email exchange with John about whether to leave the equipment permanently powered on as my JDS DAC came with an inline power switch but it also has the 15 minute standby function. I am using the JDS stack in my home office as I am currently working from home for obvious reasons. I normally have music playing while I work (typically streamed though the IDAGIO, which I really enjoy), if I need to answer a call I tend to pause the stream with the mouse as that is most convenient, which often means the DAC goes into standby before I restart the stream and I then get the pop on restart. While not painfully loud, it does make anybody else in the room jump and to be honest just sounds clunky. I get John’s point that powering up the AMP as the last component in the stream is good practice, as would be turning the volume knob down on the front of the AMP, but I am as lazy as the next person so I guess that the best solution would be to download the permanently on DAC software and skip the standby. This is not a showstopper as I am otherwise very impressed with the JDS equipment – AMP and DAC for $200 is great value – just wondering if anybody else has a similar experince and/or has come up with a better solution.
@Graham: Installing Atom DAC’s optional Sleepless firmware will prevent the mute/unmute transitions. Easy solution!
Is there any plan of balanced amp and dac from jds labs in near future???
All of our DACs are balanced internally. They happen to have a balanced-to-unbalanced stage on the end 😉
Going fully balanced necessitates a matching amplifier with balanced inputs. We haven’t ruled out the idea.
Have both the JADS Labs ATOM Dac & Amp, they work very well with Audio-Technica ATH-MSR7b closed headphones.
My Question is, is there any point in upgrading USB Cable or extra power supply filtes using IFI products, or is there no point?
@Stephen – There should be no performance advantage. You may even decrease jitter performance when deviating from the supplied, custom USB cable:
We reviewed and awarded the ATOM DAC with our Recommended Buy award! Well done!
Another satisfied customer from Greece here.Happy owner of the JDS Atom stack enjoy hearing my music through your excellent gear.
I have one question for you.I installed the xmos driver for my Atom DAC in order to use the ASIO output from Foobar and noticed that the option to choose 16/24/32 bit – 384 KHz in shared mode in Windows 10 device properties is not there.Is this normal for the XMOS driver?
PS – You should seriously consider the possibility of a central EU reseller for your products.Headsound.de unfortunately was closed and Hifiheadphones.co.uk is the only option for now albeit not the best one because of BREXIT.I am sure that the EU market could be very profitable for you.
Keep up the good work and stay safe.
Thanks, Jim. Yes, the XMOS driver supports up to 192kHz for some reason. The default Win10 drivers works fine at 32/384k, so we will ask the driver author to enable 384k in the fall 2021 release.
As for German retailers, yes, a new store is being established now!