Review and Measurements of New JDS Labs Atom Headphone Amp

[MRC01]

...
Why is the jds atom amp cheaper than the o2 when everyone says that the o2 is obsolete and that the atom is better in every way?
What is better in quality? NwAvGuy described in detail all the steps that led him to the development of O2, so I personally have more confidence in him than jdslabs
If jdslabs had the same detailed development blog, there would be more trust.

"Who ya gonna trust -- me, or your lying eyes?"
The o2 is a good engineering design. The Atom starts with a good engineering design and adds several iterations of measurement and incremental improvement. There's no trust needed -- the improvements are evident in measurements.

As an Atom owner, the sound is excellent but the build quality feels a bit flimsy. I wish they made a premium version that is electrically equivalent with higher quality materials. I'd be willing to pay an extra $100 for a metal case, higher quality connectors, smoother switches and volume knob.

What would really take the Atom over the top would be a stepped attenuator volume knob and a headphone imaging circuit to reduce listening fatigue on those occasional recordings having artificial absolute L-R stereo separation. In my book, that would make it a $500+ amp.

 

[solderdude]

What is better in quality? NwAvGuy described in detail all the steps that led him to the development of O2, so I personally have more confidence in him than jdslabs

If jdslabs had the same detailed development blog, there would be more trust.

You could trust Amirs measurements ?

The object of the game for NwAvGuy was to make a small, cheap portable amp that measured well enough (audible transparent) despite cheap components being used.
Should every design by any company be 'documented' this way to become trustworthy ?

Looking at the used parts and layout as well as independent measurements, the Atom outperforms the O2 but it isn't portable in the sense that it has batteries on board. The Atom is not a replacement for the O2.
Different use cases, different looks, different enclosure, similar price, both have a high price/performance ratio.

 

[landco]

o2

Do you have o2, can you compare with Atom by ear in a blind test?

 

[jseaber]

Because the price of something does not determine its performance. The Atom is built with plastic housing, etc., thus it is less expensive than the O2. But, it outperforms the O2 on objective measurement tests. In fact, it outperforms amps 3-4x more expensive. So, are you suggesting that JDS charge more for the Atom than the O2 as to justify its performance level?

JDS Atom vs o2

Why is the jds atom amp cheaper than the o2 when everyone says that the o2 is obsolete and that the atom is better in every way?

What is better in quality? NwAvGuy described in detail all the steps that led him to the development of O2, so I personally have more confidence in him than jdslabs

If jdslabs had the same detailed development blog, there would be more trust.

@landco - Thanks for your feedback. What specific areas of development would you like to hear more about?

I try to share as much useful information as possible, without repeating topics which have already been explained in previous years. For example, NwAvGuy discussed potentiometer channel imbalance in this article in 2011 (see `The Channel Balance Problem`). Much of the audio industry has been thoroughly explored in the past 100 years, so it is difficult to strike the right balance between being repetitive and insightful.

Objective2 was developed by NwAvGuy under a period of heavy criticism in 2011. The amplifier was meant to be a DIY project, but the project took off and became the standard community recommendation for many years. The design license disallowed changes to permit high speed assembly. Consequently, O2 has always been costly to assemble because it requires substantial manual labor. Every part is hand placed and hand soldered.

Atom Amp is an SMT design with minimal assembly labor. We are able to assemble and test hundreds of Atom Amps per day. The same team can only assemble 1/10th the number of Objective2s on a daily basis.

Anyway, what information would you find useful?

 

[landco]

Atom outperforms the O2

In some sources I have come across the fact that the Atom noise on sensitive IEMs is more distinct, and O2 does not make any noise at all

 

[solderdude]

Do you have o2, can you compare with Atom by ear in a blind test?

Both are audibly transparent' according to NwAvGuys specifications and reasoning.
There would be no point in any blind tests.

On more 'difficult loads' the Atom would 'win' b.t.w. as it can provide a higher output voltage and output current.

 

[landco]

On more 'difficult loads' the Atom would 'win' b.t.w. as it can provide a higher output voltage and output current.

Why not invite NwAvGuys to this thread, let him express his point of view?

 

[solderdude]

In some sources I have come across the fact that the Atom noise on sensitive IEMs is more distinct, and O2 does not make any noise at all

Yes, that could be the case for sensitive IEM's. The trade off for this is the 'gain issue' of the O2.
There are ways to make the Atom just as quiet as the O2 and get better volpot travel at the same time.
It is called 'ifi IEMatch' ...
But as mentioned the Atom is not portable. It is NOT intended for the same use cases / market.

 

[solderdude]

Why not invite NwAvGuys to this thread, let him express his point of view?

That would be a really neat trick

 

[GGroch]

Landco.

Sadly, NwAvGuy disappeared about 7 years ago. It would be great if he joined in, but it probably will not happen.

We are fortunate to have jseaber from JDS labs because, as you can probably tell from his answer, they make both amps.

If you did not see it yet, Amir's measurements of the Objective 2 are here.

They are very very good. Just not quite as good as the less expensive Atom.

I have both and like both. The Objective has a nicer case for sure. It also has a battery so you can use it as a portable. I would be surprised if you heard noise from either one of them. They both have well thought out Hi/Low gain settings.

BUT...I am just a guy who owns both. Jseaber can answer any specific questions authoritatively I am sure.

 

[landco]

That would be a really neat trick

What's the problem? I do not know, but surely the manufacturer has contacts NwAvGuys

 

[solderdude]

What's the problem? I do not know, but surely the manufacturer has contacts NwAvGuys

You need to ask Harold ? (I seem to recall that was his real name, but some speculate Amir = NwAvGuy and some think Archimago is NwAvGuy)
Of course those are all rumours spread by ignorant individuals
Nobody has heard from him in the last 7 years.
There is lots of talk and theories about why he remained silent since May 2012.
One of the very few who may know more is @jseaber but he does not appear to have your trust.

 

[jseaber]

Yes, that could be the case for sensitive IEM's. The trade off for this is the 'gain issue'.
There are ways to make the Atom just as quiet as the O2 and get better volpot travel at the same time.
It is called 'ifi IEMatch' ... but as mentioned the Atom is not portable.

O2 and Atom noise floor measurements are attached.

For extremely high efficiency IEMs which reveal the noise floor of any source, I suspect the 'distinct' sound comes from Atom's closer achievement to a White Noise floor. O2's higher noise floor exhibits some minor 50/60Hz AC fundamentals and harmonics, and for whatever reason, this archived test shows some spikes between 200-3000Hz. Atom Amp's noise floor is more ideal. Yes, if you can find an IEM so sensitive that noise below -140dB is revealed, I imagine you may describe the hush sound differently:
https://hyperacusisfocus.org/pink-noise/

The real concern is why IEM manufacturers build such highly efficient drivers. There is such a thing as too much sensitivity!

 

[solderdude]

Is the noise floor of the O2 measured with the volpot fully open or at '0' position ?

Agreed there is such a thing as too much sensitivity.
130dB/V IEMs will make low noise floors audible as it is spread over the entire audio band.

 

[jseaber]

Is the noise floor of the O2 measured with the volpot fully open or at '0' position ?

I always measure noise floor with the volume knob at 100%.

 

[solderdude]

The O2 will surely measure lower in noise at the 0 position and possibly not show the mains hum either.
Sensitive IEM's will always be used at the bottom of the volpot range even with 1x gain.

 

[amirm]

What's the problem? I do not know, but surely the manufacturer has contacts NwAvGuys

He has gone into hiding and the few people who know him, don't want to disclose who he is. Clearly he doesn't want to be in the limelight anymore.

BTW, the O2 has battery and charging circuits which the Atom does not. That is some cost saving there.

 

[landco]

did you discuss the problem of channel unbalance, is o2 less unbalanced at a low volume level? (up to 9 hours)

 

[MrC]

some speculate Amir = NwAvGuy and some think Archimago is NwAvGuy

I think Zeos Pantera is NwAvGuy!!

 

[jseaber]

The O2 will surely measure lower in noise at the 0 position and possibly not show the mains hum either.
Sensitive IEM's will always be used at the bottom of the volpot range even with 1x gain.

True. I'm bottlenecked by the old analyzer at 0% (attached).

Amir may have more useful measurements, or I can borrow the AP in the other office.

did you discuss the problem of channel unbalance, is o2 less unbalanced at a low volume level? (up to 9 hours)

Please see: https://www.audiosciencereview.com/...-jds-labs-atom-headphone-amp.5262/post-173191

I think Zeos Pantera is NwAvGuy!!