JDS Labs Atom DAC+ Review

[Atratusnex]

Usually different inputs don't affect SINAD/THD+N much. Jitter would change a lot and that's why Amir does jitter with different inputs.

But it can (even if it is unlikely) affect it right? i don't like it if we need to trust that the company didn't just fucked it up extremely well...

 

[H-713]

But it can (even if it is unlikely) affect it right? i don't like it if we need to trust that the company didn't just fucked it up extremely well...

It's a balance. Amir could spend a week testing each DAC, but unless he completely reverse-engineers it, analyzes every design choice and measures every parameter, you still have to have some faith in the engineers who designed it.

If you really don't trust the companies who make this stuff, then there is nothing stopping you from designing your own DAC.

Going down the rabbit hole with DAC measurements is rather pointless, since it's generally the most transparent part of the audio chain. As things get less transparent, it becomes possible to go even further down the rabbit hole. Want to fully test a power amp? First, let's see how it performs with a whole bunch of different reactive loads. Now let's do that over a wide range of temperatures. You can spend a ridiculous amount of time just testing the thermal tracking in the output stage. Let's also do some slew rate measurements. Input CMRR (if it has balanced inputs). Dynamic headroom matters if the amp is going to get pushed. If we assum that the amp will be pushed hard, we should also look at how it clips, since an amp that clips gracefully will sound different from one that overshoots and oscillates, or one with a really badly designed peak limiter. While we're at it, let's see if the engineers did their homework with the design of protection circuits. Does the amp blow up when you short the outputs? How much DC on the output does it take to trigger the protection circuits? Is the speaker relay capable of breaking the connection if an output device shorts with a heavily inductive 4-ohm load connected?

I would argue that ALL of those tests are very reasonable to run. I've seen amps with protection circuits that don't protect the amplifier or the loudspeaker. I've also seen amps with no protection circuits. I've seen plenty of amps with marginal stability, and a lot of amps that can't even come close to making their claimed output power.

So... how far down the measurement rabbit hole do you really want to go?

 

[Robbo99999]

So, weren't we talking about clipping off the bottom 25% of the SINAD list at this point? I mean, if a product can't hit 100dB on that chart now, they're probably not in consideration for anyone on this site, regardless of price. It's probably time to recalibrate...

Thanks for bring this to us, as always, Amir (and JDS for that matter!).

Along the lines of what you're thinking, it could be divided into two charts to ease readability, bottom 25% or whatever in the other chart.

 

[drake5000]

Thank you for the review! Any chance to see Jitter for Toslink input?

 

[magicscreen]

Plastic case? Trash.
I can buy Fx-Audio Tube-03 for $30 with a metal case.
Are Americans thinking they can sell any trash for money?

 

[Atratusnex]

It's a balance. Amir could spend a week testing each DAC, but unless he completely reverse-engineers it, analyzes every design choice and measures every parameter, you still have to have some faith in the engineers who designed it.

If you really don't trust the companies who make this stuff, then there is nothing stopping you from designing your own DAC.

Going down the rabbit hole with DAC measurements is rather pointless, since it's generally the most transparent part of the audio chain. As things get less transparent, it becomes possible to go even further down the rabbit hole. Want to fully test a power amp? First, let's see how it performs with a whole bunch of different reactive loads. Now let's do that over a wide range of temperatures. You can spend a ridiculous amount of time just testing the thermal tracking in the output stage. Let's also do some slew rate measurements. Input CMRR (if it has balanced inputs). Dynamic headroom matters if the amp is going to get pushed. If we assum that the amp will be pushed hard, we should also look at how it clips, since an amp that clips gracefully will sound different from one that overshoots and oscillates, or one with a really badly designed peak limiter. While we're at it, let's see if the engineers did their homework with the design of protection circuits. Does the amp blow up when you short the outputs? How much DC on the output does it take to trigger the protection circuits? Is the speaker relay capable of breaking the connection if an output device shorts with a heavily inductive 4-ohm load connected?

I would argue that ALL of those tests are very reasonable to run. I've seen amps with protection circuits that don't protect the amplifier or the loudspeaker. I've also seen amps with no protection circuits. I've seen plenty of amps with marginal stability, and a lot of amps that can't even come close to making their claimed output power.

So... how far down the measurement rabbit hole do you really want to go?

I don't want him to go down the measurement rabbit hole, even if I think some of what you wrote would be quite interesting (positive). I argued only

it seems like @amirm is testing what he wants, depending on how he feels... sometimes more, sometimes less. That's fine, but this might not work for this type of list ...

that if we make connection exclusive lists (USB- list, toslink, coax -list etc) for SINAD that we maybe shouldn't then use values from other connection types then measured.

 

[Atratusnex]

Plastic case? Trash.
I can buy Fx-Audio Tube-03 for $30 with a metal case.
Are Americans thinking they can sell any trash for money?

It isnt trash.. It is most likely just the economic reallity of producing in usa, paying decent wages, offering good customer service.

Somthing has to give if you want to stay competitive on price.... And the inside is more important here then looks or the case.

Never seen any Fx-Audio doing well.. By the way

 

[Veri]

Plastic case? Trash.
I can buy Fx-Audio Tube-03 for $30 with a metal case.

Just imagine of how questionable quality the inside components must be if you can buy something so cheap with a proper case....

 

[bennetng]

Modi3+, $99 with metal case and measured well.
https://www.audiosciencereview.com/forum/index.php?threads/schiit-modi-3-review-stereo-dac.18480/

PS: I am Asian.

 

[bboris77]

Regarding plastic vs metal - I never really understood why specifically in audio we tend to put so much value on this. In most other entertainment consumer products it’s a non-issue. Look at any PlayStation or Xbox consoles and controllers - all plastic.

Metal has an advantage of dissipating heat much better when used as a heat sink. It is also heavier which is very useful for headphone amps because you need to plug stuff into them and adjust the volume all the time. Other than that, I genuinely see no advantage to using metal.

Even for things like RFI and EMI resistance, the Atom amp and DAC have been the most effective at rejecting it. Just shows you that proper engineering and testing beats the brute force approach.

In terms of disadvantages of metal - unpainted aluminum is soft and scratches easily, ESD and case grounding can be a challenge and QC when it comes to metal finishing can be a nightmare. I’m basing this on a number of conversations I’ve had with manufacturers and my own experience with various products over the last 10 years.

Let’s talk briefly about cosmetics. Sure, high quality metal cases can look spectacular but high quality plastics can look great too. The original PlayStation 3 and PS2 are classics. The HD800S is beautiful as well and it is mostly plastic.

In conclusion, not all grades of plastics are the same. There should be no direct correlation between the use of plastics in products and cheapness.

 

[Labjr]

The enclosure for the Atom DAC doesn't look like a Playstation. It looks cheap and flimsy.

 

[bboris77]

The enclosure for the Atom DAC doesn't look like a Playstation. It looks cheap and flimsy.

Lol...depends on your tastes...For example, the PS5's design is not everyone's cup of tea either.

Have you actually owned one though? I am asking because I have and I can tell you that the quality of plastics used is very good. It is not some cheap brittle garbage that will crack or scratch if you look at it sideways. I am not sure if @jseaber wants to disclose the specifics here, but it would be interesting to know what kind of testing they have done on its durability etc.

As for the comparison with the Modi 3 with its classic Schiit aluminum case, I owned one as well, and it is a great DAC. However, it uses the micro USB connector which I did not like and it could not reject the radio interference in my particular situation (close to an airport radar) as well as the Atom DAC does so I sold it.

 

[Atratusnex]

Modi3+, $99 with metal case and measured well.
https://www.audiosciencereview.com/forum/index.php?threads/schiit-modi-3-review-stereo-dac.18480/

PS: I am Asian.

Differnt scale of company, most likely different scale of production.
And i didnt forgot schiits scandals... Nor did i forgive the NwAvGuy situation... But that is OT.
Point is : there are different reasons for differnt persons for buying products... That is fine

PS: couldn't care less

 

[TurtlePaul]

I don't want him to go down the measurement rabbit hole, even if I think some of what you wrote would be quite interesting (positive). I argued only that if we make connection exclusive lists (USB- list, toslink, coax -list etc) for SINAD that we maybe shouldn't then use values from other connection types then measured.

I see where you are coming from that we should have like-for-like measurements, not just Amir testing whatever input he fells like. However, my original suggestion was not really intended to be having lists for each input type, but more about having lists with 10-20 items that people are likely to cross-shop for the sake of brevity and legibility.

I could see people cross shopping the Topping D70, Benchmark DAC3 and RME ADI-2, those are all DACs with volume controls and balanced pre-outs. I could see people cross shopping the JDS Atom DAC, Schiit Modi 3, and Topping D10, those are all USB DACs with line-level RCA outs. I can see cross shopping various disc players, or AVRs, or streamers. What doesn't make any sense at all is having all of these devices in the same list now that 100+ devices have been tested.

 

[Zensō]

Plastic case? Trash.
I can buy Fx-Audio Tube-03 for $30 with a metal case.
Are Americans thinking they can sell any trash for money?

John Seaber, from the JDS Blog:

Metal Case?
A few visitors have inquired about a rumor that JDS Labs will release Atom Amp in a metal case. This rumor is just that.

We’ve invested considerably to our in-house machine shop, and are certain that our CNC’s cannot keep up with Atom Amp’s demand at the current price point. Even a price increase of +$50 would be insufficient to build something like Element. Yes, we could revert to an aluminum extrusion with front/rear plates like the older Objective line. But we’ve done that. It’s boring and ugly. Why raise cost to take a step backwards? How about stamping? Already been done. We decided to try injection molding for Atom for the following reasons:

• Consistency – Every unit is the same without variations in finish.
• Flexibility – More mechanical design options compared to metal.
• Scalability – We can build a million just as easy as one. Increasing production with metal demands more machines.

We’re happy with the end result because we’re able to assemble Atom Amp quite efficiently as designed, and focus expenses on genuine components and top-tier SMT assembly in the United States. That said, we’re passionate about working machined aluminum into future releases where doing so makes sense.

 

[bennetng]

PS: couldn't care less

Of course. Because I was replying to another member, as a disclaimer that I am not pro-US.

 

[jseaber]

"We purchased a new APx555" seems like a frequent marketing spiel, but honestly, I doubt that in 2021 any proper company that design DACs, aside maybe one man DIY style stuff, fully send their work to the world without one, since it's the only measuring device that can attest up to optimal performance of modern chips in a design. Not everybody own one but at the very least I'd assume you rent one for a month, which in many case is sufficient.

I appreciate all the kind remarks and constructive feedback!

To chime in on this topic, keep in mind we've been around for 14 years and our first analyzer was a Prism dScope Series III. Analog input resolution of the dScope is a bit better than an APx525. When we released Atom Amp in 2018, I knew it measured better than our dScope, and was not concerned by how much better. We had no idea Atom Amp would render anything older than an APx525 so obsolete! Many manufactures choose to invest in the APx555 as a response.

Our APx555 is not meant as a marketing spiel. Rather, it's made my job faster and easier. Thorough D/A tests consumed about 30 minutes per run on the dScope due to manual setups and slow averaging. The APx555 runs the most valuable tests in a couple minutes automatically. So, I can ponder hardware and firmware tweaks while a trusted technician runs dozens of iterations in one afternoon. Results are saved to a shared folder of PDFs. It's incredible how quickly ideas come together with the right tools.

The race to bigger numbers has been fun. Alas, we're all so far beyond transparency today that it's time to ponder what matters in bringing more enjoyment to this hobby in the next decade.

 

[PuX]

Give me a balanced version for my Genelec (and keep the toslink) for about 199 or under and i will buy it jds.

same, I feel like JDS needs to have a competitor to Modius.
I don't know if balanced DACs sell well though, maybe that's why JDS only has models with RCA out.

 

[Budgeter]

Finally something to pair with my Atom amp. I've been using Topping D10 with Atom amp for like 2 years now. While the pair has no problem, aesthetically it is kinda meh to me, and not having a toslink input is also a downside. @jseaber, can you consider making a guide on how to bit perfect atom dac on Linux?

 

[MRC01]

... @jseaber, can you consider making a guide on how to bit perfect atom dac on Linux?

I wrote a guide to Linux audio, maybe it's helpful for others.