Review and Measurements of New JDS Labs Atom Headphone Amp

[thomasjast]

Got my Atom yesterday and tested it thoroughly. Channel balance is basically flawless after the 1o'clock knob position (tested with 1Khz sine wave output VU monitoring on Line-In), always within 0.1dB and sometimes 0.0dB difference.

I am really impressed with this thing. First device that made my AKG K7XXes sound like this. Exceptional device that deserves all the praise it gets.

 

[Music1969]

Yes.

I had the same issue with sensitive Focal headphones (105 dB/mW).

I stick to DAC/Amps with digital volume control.

 

[florence]

Has Atom sufficient power to drive HD800 efficiently? I don't mean measurements of the amp, I mean while driving the cans maintaining the dynamics, detail and imaging?

 

[Veri]

Has Atom sufficient power to drive HD800 efficiently? I don't mean measurements of the amp, I mean while driving the cans maintaining the dynamics, detail and imaging?

???

anyway the answer is yes.

 

[GGroch]

How about the atmosphere, rhythm and engagement?

 

[maxxevv]

Has Atom sufficient power to drive HD800 efficiently? I don't mean measurements of the amp, I mean while driving the cans maintaining the dynamics, detail and imaging?

Emphatically : Yes.

Subjectively : Better than a few other amps I have tried with the HD800.

 

[florence]

Emphatically : Yes.

Subjectively : Better than a few other amps I have tried with the HD800.

Thanks for response. What other amps have you tried and failed comparing to Atom?

 

[magicscreen]

Also, idsd micro bl with HD800 too much sterile to my ears if you ask me why I'm looking for alternatives as an amp.

The JDS Atom with HD6XX is too much sterile to my ears.
UAPP->cheap OTG USB cable->Marantz PM7005 inner DAC (CS4398)->cheap RCA->Atom->HD6XX.
The Atom sounds for me like an entry-level amplifier, I am very disappointed.
Any idea what should I upgrade/change?

 

[Veri]

The Atom just amplifies. If you want sound to change or get 'warmer' you need something else...

 

[Silou]

The Atom sounds for me like an entry-level amplifier, I am very disappointed.
Any idea what should I upgrade/change?

The Atom does not sound at all. If you do not like the sound than your headphone is the problem.

 

[MrGoodbits]

The JDS Atom with HD6XX is too much sterile to my ears.
UAPP->cheap OTG USB cable->Marantz PM7005 inner DAC (CS4398)->cheap RCA->Atom->HD6XX.
The Atom sounds for me like an entry-level amplifier, I am very disappointed.
Any idea what should I upgrade/change?

You may be expecting an amp to do too much. I'd keep the Atom.

In the last few months I spent several hours per day listening to Atom and THX 789, also Schiit Magni 3 and DragonFly Red. The headphones I used were mostly Sennheiser HD600, with some Etymotic ER4SR, NAD VISO 50, Senn HD 25 C II and HD 580CS. And I've honestly just not heard any difference at all between the four amps. The overall sound is really, really good, enough that I'm convinced any audible difference between these amps would be apparent by now. Like, playing the master tape directly into your brain "good" : )

My recommendation is to keep your current setup and look into headphone EQ and crossfeed for meaningful improvements. You could get better headphones but it would mean a lot more $$$.

 

[trl]

Thank you for your detailed reply. I have a HE-560 and I believe it needs more power than the Atom can provide.
I hope @tomchr can release more information about HPA-1.

Just used few minutes ago a 1KHz sinewave on my HE-560. I could barely listen to 1V RMS for few seconds; hope tinnitus will spare me this time.

I used the same volume knob position and played regular songs (average to high compressed songs, 2019 pop music) and found that knob level needs to be increased. With cans out of my head I played the same 1KHz sinewave and I measured 2V RMS with my scope. When switching to highly dynamic Chesky music I needed to increase volume even further, somewhere where 1KHz sinewaves will get to about 3V RMS.

My personal conclusion would be that if an amplifier was designed to deliver the max. output power for an input of 2V RMS, then with music playing it might never get to full power, especially with dynamic music with peaks that barely get to -3dB. Probably this is why most amplifiers are delivering full power for an input of 0.7...1V RMS.

So, in HE-560's case, definitely Atom can drive HE-560, but also any headamp able to deliver 3-4V RMS on the 6.3mm jack for 1V RMS on its RCA inputs (a gain of 3...4X).

 

[elnan14]

The JDS Atom with HD6XX is too much sterile to my ears.
UAPP->cheap OTG USB cable->Marantz PM7005 inner DAC (CS4398)->cheap RCA->Atom->HD6XX.
The Atom sounds for me like an entry-level amplifier, I am very disappointed.
Any idea what should I upgrade/change?

This is the upgrade you need: ASR -> head-fi

 

[maxxevv]

Thanks for response. What other amps have you tried and failed comparing to Atom?

On a personal level I have a Matrix HPA-3B, a Burson Playmate (review set) and between them, its a tie for the Matrix and the Atom though the presentation is marginally different. Smooth effortless power with plenty of punch when called for from the music.
The Burson somehow (came with 5534 opamps) sounded a little brighter with the HD800 and sounded excellent with the HD6XX. The brightness being more obvious when it came to the HE4XX.

I've tried the HD800 on various different amps at 2 editions of CanJam. Including the HDV820, the SMSL P1. The show conditions are not entirely representative but those amps didn't make the HD800 sound 'better' in any definitive way compared to the ATOM paired with a KTB anyway.

 

[NTK]

...
You could get better headphones but it would mean a lot more $$$.

That may not necessarily be true either. Dr. Sean Olive at Harman conducted a sound quality test of 61 in-ear headphones, with the most expensive one at $3k a pair. He concluded there was no correlation between price and sound quality. The "best sounding' headphone was a $100 pair EQ to the Harman target curve. So, if Dr. Olive is correct, we can get the very best headphone sound for under $300 USD (DAC + amp + headphone).
https://seanolive.blogspot.com/2017/02/twirt-337-predicting-headphone-sound_17.html

 

[Quizel]

He concluded there was no correlation between price and sound quality.

I read that before too and got confused. How resolving a headphone is isn't really represented in just a frequency response graph. THD vs Frequency at various power levels (SPLs) is kind of important imo as well. There are other metrics that can be measured that I'm not going to post since I have less understanding of them. The point is I think Dr. Sean Olive is nuts

 

[solderdude]

Well if those very expensive IEM's happened to some Final Audio (audio jewelry) or the oBravo then I can understand there is no relation to price.
Furthermore with IEM's insertion depth and seal are very important as are aspects like ear canal length and shape.

The problem with ear-headphones is that what is one man's great sound is another ones 'meh'.
This is clearly shown in the over- under-rated thread as well as other threads discussing headphones.
Taste, preference, type of music, seal, on-over-in ear it all matters.

And I agree FR is the largest factor but even when you EQ a turd into a flagship they won't sound the same.

 

[BDWoody]

How about the atmosphere, rhythm and engagement?

Don't forget the plankton situation...

 

[NTK]

Well if those very expensive IEM's happened to some Final Audio (audio jewelry) or the oBravo then I can understand there is no relation to price.
Furthermore with IEM's insertion depth and seal are very important as are aspects like ear canal length and shape.

The problem with ear-headphones is that what is one man's great sound is another ones 'meh'.
This is clearly shown in the over- under-rated thread as well as other threads discussing headphones.
Taste, preference, type of music, seal, on-over-in ear it all matters.

Dr. Olive did use the term in-ear headphones in his blog post, that's why I used it in my post above. However, I did remember him discussing the difficulty of hiding the identity of the Audeze headphone from the listeners because of its weight (and that they attached little handles to the headphones so the listeners could adjust fit without actually touching to hide the identities of the headphones). Obviously that wasn't an IEM. So I don't know if he meant IEMs or he was referring to all styles of headphones in general.

And I agree FR is the largest factor but even when you EQ a turd into a flagship they won't sound the same.

No disagreement here. But I think Dr. Olive's point is that a competent headphone that can be effectively EQ to produce world class sound can be had for about $100 USD.

 

[solderdude]

I think Dr. Olive's point is that a competent headphone that can be effectively EQ to produce world class sound can be had for about $100 USD.

Lets say I respectfully disagree with dr Olive here.
There is much more to headphones than FR.
Cone break up, resonances, acoustic nulls to name but a few obvious ones would be hard to simulate.
Not to mention comfort, feel, proper positioning on the head.

I do think they are doing the whole industry and themselves a good service though.
If anything, a lot of folks aren't afraid to use the word 'EQ' any more.