JDS Atom Amp+ Review (Headphone Amplifier)

[usern]

Weightier low end?

Good news for Slam & Punch

 

[pk500]

Now I would be pleased if JDS Labs would come out, with a more powerful version of the Atom, something able to push 5 Wpc at 10 ohms... With same performances and reliability
I'd buy it the second it is announced.

Peace.

Don't count on it happening any time soon. John Seaber is not a general in the "watt wars" of this industry.

JDS did release a "boosted" version of the Element 3 late last year, with a doubling of output to around 2.5 wpc at 32 ohm, I believe. He wrote about that in this blog post, which started with these two paragraphs:

"We’ve long maintained that most headphones on the market need below 1W of power for normal listening. This is why all of our recent amplifiers have been designed around this figure–until now. Element III Boosted is for those of you with an appetite for ill-advised volumes from the world’s most power-hungry headphones.

"No, we still have no interest in a spec race. In all honesty, we built Element III Boosted after a customer pointed us to a discussion claiming that JDS amplifiers were incapable of powering inefficient headphones. Rather than continue to preach that enough-power-is-enough, we ordered a larger dummy load and assembled a more powerful Element III."

The man speaks my language, another reason why I'm a loyal JDS customer. Granted, I've never owned super-inefficient headphones like Susvara. Abyss, HE6se, etc., but I snicker when I see posts INSISTING an Edition XS or an HD600 MUST have 3 or 4 wpc to "reach peak fidelity." That's spec chasing, not reality, at least to my ears.

I would rather have enough clean power built reliably than enough power to send a rocket to the moon but with noise, shoddy build or crap quality control. Maybe that's just me.

Some of these amps that feature 4 to 6 wpc at 32 ohms are great if your headphones REALLY need that just to be heard. I know there are a few models that demand that kind of power. But otherwise, those just remind me of a guy who buys a muscle car because it goes from 0 to 60 in 4.9 seconds -- 4 seconds quicker than your family sedan -- and then just uses that car to tool around town for errands and the odd highway trip.

Good for them. I see it as total overkill.

 

[Extreme_Boky]

Yeah, ordinarily I’d think it was a fluke, but two different brand new units both doing it..? Come on.

I find that the reviews here maybe focus too much on microsopic measurements to the point where basic, practical usability is thrown out the window. So it measures great, cool, when referencing audio in a professional studio environment that’s important, but the channel balance is awful* (and so common that it’s specifically mentioned on the JDS site), the wall wart is massive and the unit itself is so light and cheap that it’s prone to sliding around on a desk when simply interacted with. Their 15-day / 15% return policy is a joke, as well.

So, yeah, if you want to spend $99 on an amp that measures perfectly* but is a PITA to actually use then this is the one.

Well, their marketing material praises the "hand-matched volume channels"... the main reason why I wanted to buy one, knowing how crappy that volume pot (mechanical/assembly) channel matching is... As expected, no matching took place.... thanks for the feedback.

I think the only way to use these amplifiers that have volume potentiometers, is to bypass them (bridge them out on a PCB), and then use the source's volume control...

 

[jseaber]

Well, their marketing material praises the "hand-matched volume potentiometer gain"... the main reason why I wanted to buy one, knowing how crappy that volume pot (mechanical/assembly) channel matching is... As expected, no matching took place.... thanks for the feedback.

The potentiometer gangs are hand matched by the OEM prior to assembly in Atom Amp. Our team listens to every Atom Amp at various volume positions during final Q/C. It's true that channel balance of a 9mm pot will be imperfect below about -40dBFS. That said, I take channel balance seriously, and our potentiometers exceed balance requirements of typical Alps RK097 series pots to volumes an order of magnitude lower. Only 1 customer in the past year has reached out for help; he was listening below -40dBFS.

If you are after absolutely perfect channel balance at all levels, by all means, avoid amplifiers with 9mm pots. We created Element III for this reason!

 

[Extreme_Boky]

The potentiometer gangs are hand matched by the OEM prior to assembly in Atom Amp. Our team listens to every Atom Amp at various volume positions during final Q/C. It's true that channel balance of a 9mm pot will be imperfect below about -40dBFS. That said, I take channel balance seriously, and our potentiometers exceed balance requirements of typical Alps RK097 series pots to volumes an order of magnitude lower. Only 1 customer in the past year has reached out for help; he was listening below -40dBFS.

If you are after absolutely perfect channel balance at all levels, by all means, avoid amplifiers with 9mm pots. We created Element III for this reason!

That is all nice and sweet but despite your rigorous QC, two Atom amps ended with a single customer who dared to complain, and I personally thank him for that... those amps are unusable (unless pots are replaced or bypassed).

 

[Extreme_Boky]

You're taking one guys post over tons of posts from satisfied owners. Smh, you sound like a moron.

No, I wanted to buy an amp... and did my homework, researched the customer feedback, saw the marketing blurb about hand-matching the channels and realised that was simply not the case. Either OEM did not do their job, or the QC did not do their job...

I do not understand why such a brutal response.... you do not know anything about me, who I am and what I do....

Anyway, there was honest feedback provided back to the manufacturer, that, it seems, cares about the product and may take it as a continuous improvement opportunity to ensure the channel mismatch does not happen...

 

[jseaber]

That is all nice and sweet but despite your rigorous QC, two Atom amps ended with a single customer who dared to complain, and I personally thank him for that... those amps are unusable (unless pots are replaced or bypassed).

To clarify, I agree something does not seem right here. There should never be such unacceptable balance, especially across two samples. Let's get to the bottom of this.

@anynameiwish: May I send you a prepaid return shipping label? I'll be glad to inspect and refund both amplifiers if you still have them, and share findings here. Please PM me with your order information.

 

[jseaber]

No reply from the above yet, of course, I am weeks late to the discussion. In the meantime, I pulled all RMAs assigned to Atom Amp(+) owners dating back to release:

• Atom Amp (2018-2020, original Alps RK097 pots) - Several requests for channel balance checks, representing 0.083% of amplifiers shipped in this period.
  
  
• Atom Amp+ (2021 onwards, hand matched pots) - Only 1 request for a channel balance check at "low volumes", representing < 0.01% of amplifiers shipped.
  The gangs were on the edge of our custom matching specifications below about 9 o'clock, and in spec beyond 10 o'clock. We replaced the potentiometer and verified that channel balance was within 0.1dB at a low listening level of -35dB. The customer replied:

I received the amp today and it's significantly better than before. I really appreciate everything that went into this request.

The above figures exclude one unusual RMA assigned in Oct 2022: "Customer will return 2x Atom Amp+'s and 1x Element 3, claiming all have channel imbalance".
We could not replicate his findings. About 30 emails later, the customer replied:

Because I am starting to feel a bit like I am going insane, I wanted to do some more testing. [. . .]

My conclusion here is that a) the [competitor product] seems to be biased toward the right while the H5's input is balanced toward the left, so they cancel each other out and b) I owe you an apology. Indeed, actually listening to the sine sweep through the [competitor product], it's pretty inconsistent across the frequency range, with the low end having a pretty substantial left bias and the rest kinda going back and forth. I cannot explain why it sounded to my ears like there was a left bias with the JDS units except that maybe my ears aren't so great after all. I mean, looking at your results of the Element, it does seem to have a slight left bias, but I am not foolish enough to think I can hear a 0.01 dB difference. Maybe it was just confirmation bias, I don't know. At any rate, I'm sorry. You have clearly done far more than your due diligence (and I really appreciate that) on this and I think I am just wrong. I would also like to thank you for actually listening to me and believing me even though I ended up being wrong. It's refreshing to not have to explain myself 500 times to a support agent...

He ultimately kept the Element III, case closed.

This is not to discredit anyone. Problems happen even to intelligent people with simple setups. We do our best to help when weird problems arise. Every RMA request is documented for analysis and improvement, with the obvious goal of zero repair requests.

All of that being said, channel balance was essentially solved with the release of Atom Amp+. But hey, mistakes can happen, and we try to help and learn where we can.

"anynameiwish"'s claim is exceptionally unusual, and as far as I can find, he never contacted us. In the event that we fail to fulfill a promise or claim, we cover all return costs. DOAs or otherwise bad audio should never occur. But if something goes wrong, I owe you.

As for remarks on lightweight build quality, yes, I agree. We've since released Atom Amp+ HEVI. Our staff wants to discontinue the original enclosure. We shall see.

Side note: Support is both a strength and weakness of JDS Labs. We might be a 10x larger company today with different values. Not every customer will be happy, and more often than not, it's better to listen, learn, and move forward.

The man speaks my language, another reason why I'm a loyal JDS customer. Granted, I've never owned super-inefficient headphones like Susvara. Abyss, HE6se, etc., but I snicker when I see posts INSISTING an Edition XS or an HD600 MUST have 3 or 4 wpc to "reach peak fidelity." That's spec chasing, not reality, at least to my ears.

Thank you!

 

[lcelm]

This is not to discredit anyone. Problems happen even to intelligent people with simple setups. We do our best to help when weird problems arise. Every RMA request is documented for analysis and improvement, with the obvious goal of zero repair requests.

All of that being said, channel balance was essentially solved with the release of Atom Amp+. But hey, mistakes can happen, and we try to help and learn where we can.

"anynameiwish"'s claim is exceptionally unusual, and as far as I can find, he never contacted us. In the event that we fail to fulfill a promise or claim, we cover all return costs. DOAs or otherwise bad audio should never occur. But if something goes wrong, I owe you.

Side note: Support is both a strength and weakness of JDS Labs. We might be a 10x larger company today with different values. Not every customer will be happy, and more often than not, it's better to listen, learn, and move forward.

Being my first ever post to an ASR Forum thread, I would first like to thank Amir and all of the contributors who provide some really great information, insight, and feedback.

I have been doing a lot of research looking for an entry level DAC and HP Amp to hook up to a new Intel NUC 12 I recently purchased for my home office. Wanting to stay in the $150 to $250 range, I was torn between a JDS Atom+ Stack, Schiit Modi/Magni+ Stack, Fiio K7, Topping DX30 Pro, or SMSL C200 going back and forth between them. I had read and watched numerous opinions, reviews, etc. and came down with a really bad case of analysis paralysis.

Reading through this thread and the post by @jseaber has cured my paralysis. I went ahead yesterday and ordered an Atom+ Stack (HEVI). Looking forward to an upgraded home office music experience!

May the 4th be with you!

 

[Music1969]

2 years on and this is still one of the best amps to buy for RCA input only

I wish they make a balanced input version and relay based vol control, obviously cost more - USD200? @jseaber

Or even chip based analogue vol control, if there's a high SINAD one out there

 

[jseaber]

2 years on and this is still one of the best amps to buy for RCA input only

I wish they make a balanced input version and relay based vol control, obviously cost more - USD200? @jseaber

Or even chip based analogue vol control, if there's a high SINAD one out there

Thanks! Chip based volume controls are appealing. We've found that volume attenuation on the front of modern D/A converters works best, requiring an amp+DAC. ESS's zero-detection during volume adjustments is particularly useful. Relays are one of the most expensive options to consider, at $1-2 each + MCU + gates and passives.

Not going to dive into the balanced discussion today...

 

[Chesapeake HT]

Now that my wife and kids are out of school for the summer, teleworking is not as “peaceful” and listening to music is a little tougher. So I decided to get a set of HD 650s and an Atom Amp+ to go with my Atom DAC+ and help with my listening enjoyment! J. Seaber was more than patient with my questions before and after the purchase. Everything sounds wonderful together.

I was surprised to receive not only an awesome engraved HEVI version, but the entire thing is an all metal enclosure. Apparently a limited run batch. Very cool.

Thanks for the reviews and input from this site to make confident sound investments.

 

[e_h]

I'm considering different options to get more power and better sound for my headphones. My setup today is PC USB>SoundblasterX G6>HD800S, with EQ APO pregain set to -12db. I would add the Atom Amp+ after the SBX G6 (the latter being used as DAC and for virtual surround), connecting them with a 3.5mm cable.
Currently Windows volume 100 is just enough for my ears, but I want to optimize audio quality and have decent headroom (for peace of mind if nothing else).

- Would there be any point at all for me to be looking at something more powerful than this device?
- Could I get better audio quality elsewhere, by spending more money? (I've been eyeing the RME ADI-2 Pro FS BE since it could be used as a digital interface for my Genelecs as well, plus I could use its PEQ instead of PEACE, but I suppose the RME is rather overkill if the main purpose is headphone amp.)
- Are there any other features (balanced output?) that would in any way add to my listening experience?

 

[MRC01]

I'm considering different options to get more power and better sound for my headphones. My setup today is PC USB>SoundblasterX G6>HD800S, with EQ APO pregain set to -12db. I would add the Atom Amp+ after the SBX G6 (the latter being used as DAC and for virtual surround), connecting them with a 3.5mm cable.
Currently Windows volume 100 is just enough for my ears, but I want to optimize audio quality and have decent headroom (for peace of mind if nothing else). ...

It sounds like you need a bit more voltage gain to compensate for your -12 dB pregain. My HD580 headphones have similar voltage sensitivity to your HD800S. On my Atom, I use low gain despite -6 dB in DSP to correct their bass attenuation. Based on this, the Atom should have plenty of gain and power for your HD800S.