Review and Measurements of New JDS Labs Atom Headphone Amp

[JohnYang1997]

The Atom includes a SMPS, switching mode one. Linear power supplies are known to be better than smps, and most output DC, not AC. For example Topping sells a LPS for their DX3 Pro and D50 dacs.

Atom uses lm317 and lm337 which are linear regulators. This is linear power supply. The wall wart is 220/110V AC in and 16VAC out and it's literally a transformer. The rectification and regulations are in the unit just like solderdude said.

Topping dx3pro d50 etc use 15V smps and 5V smps which are different from what atom uses.

Also there is no direct which is better. Best performing amps like thx 789 thx 887 hpa4 neurochrome hp-1 are all using smps. Hope this tells you something.

 

[solderdude]

The Atom includes a SMPS, switching mode one. Linear power supplies are known to be better than smps, and most output DC, not AC. For example Topping sells a LPS for their DX3 Pro and D50 dacs.

As John Yang already mentioned. The Atom comes with a 16V AC adapter which is not an SMPS.
The 16VAC is rectified and regulated inside. There is nothing switching in there. Well, the relays do.
The one on the PCB near the power inlet switches the power on and off, triggered by the volpot.

Switching power supplies can be better than linear ones. It depends on the design.
There are excellent switchers and excellent linear power supplies and there are also poor ones in both topologies.

 

[wyup]

I'm not an expert but Linear Power Supplies are different than what the AC adaptor and the Atom seem to include. They are heavier because they have a heavier toroidal transformer, apart from regulator and rectifier. I'm not talking about stock topping dx3pro or d50 smps, but a separate LPS they sell. Of course it depends on implementation, but usually LPS are more expensive so I assume they are better. I suppose they sound better, though I've just read another article from Amir that says LPS don't improve on Topping dx3 pro. As Atom is an amplifier I just wondered if the LPS would be more noticeable.

 

[JohnYang1997]

I'm not an expert but Linear Power Supplies are different than what the AC adaptor and the Atom seem to include. They are heavier because they have a heavier toroidal transformer, apart from regulator and rectifier. I'm not talking about stock topping dx3pro or d50 smps, but a separate LPS they sell. Of course it depends on implementation, but usually LPS are more expensive so I assume they are better. I suppose they sound better, though I've just read another article from Amir that says LPS don't improve on Topping dx3 pro. As Atom is an amplifier I just wondered if the LPS would be more noticeable.

That's not how you categorize power supplies.
Atom takes AC input and uses linear power supply. No need to argue, it's linear topology period. The transformer you are looking for is in the wall wart. It's quite heavy comparing to smps. Does atom need more beefy power supply? 240ma each channel from two lme49600, you can't use even 500ma in any way. So there is absolutely no need for a beefier transformer.
Also linear power supplies are not always more expensive.

 

[solderdude]

As Atom is an amplifier I just wondered if the LPS would be more noticeable.

You cannot use an LPS with Atom.
It needs AC and can only work on AC. So you cannot try one... period.
All you can do is use a 100W/16V AC transformer but that won't bring any changes except in the mind.

SMPS can be much smaller than 50/60Hz transformers with the same power rating because of the mains frequency.
The SMPS works with a much smaller, lighter and cheaper transformer that is switched on a very high frequency.

The same people that swear they hear differences between interlinks, power cables and beeswax filled fuses will definitely hear differences with a much more expensive and heavy power supply. Regardless of them being switching or linear. But only they have the ability to hear improvements.

 

[wyup]

Sorry, I hadn't realised it uses a AC/AC power adaptor.

 

[DivineCurrent]

I have a newbie math question. The Atom puts 250 mW into 300 ohms (in high gain), and 1.1 Watts into 33 ohms. Could I derive the amount of power the Atom puts into other ohm loads based on this info, specifically 80 ohms? If I were to guess, is it around 750 milliwatts? I'm just trying to find out how much power I realistically need for the Focal Elex with another dac+amp, because the Atom has more than enough power to drive it, even in low gain. I'm looking into an all in one DAC+amp like the Topping DX3.

 

[solderdude]

The Elex is very quite sensitive and doesn't need much power.
The Atom will provide almost 1W into 80 Ohm = 124dB peak SPL.
Calculations are not linear. They are related to max output voltage and current limit.
At 80 Ohm the power is directly related to the output voltage as the current limit is not reached yet.
You will have dialed down the volume before you reach the 1W level for sure.

 

[iazriel]

We had a conversation with a friend the other day and I would like more opinions on the matter, like a small poll. Which of the following combination would you use for gaming and why?

JDS Atom+Topping D30+HeSuVi surround emulation VS JDS Atom+Sennheiser GSX 1000.

Heaphones in both cases are DT 990 Premium.

 

[Irrenarzt]

Noob here, looking to have a low distortion solid state solution for driving Sennheiser HD 600 cans on an already crowded desktop. I currently am plugging directly into my Mac Mini minijack port, but want to do a DAC/amp combo. Is the Atom/KTB still the way to go? I've read a bunch of posts over the weekend, and it seems like Atom/KTB is the best bang for your buck.

 

[trl]

Is the Atom/KTB still the way to go?

Yes, why not? Both are measuring very well and the cost is rather low. You will also need to purchase a case for the KTB and probably a low-noise power supply.

Feel free to check https://www.audiosciencereview.com/.../master-index-of-audio-hardware-reviews.8184/, seems that Modi 3 and Magni 3+/Magni Heresy measure pretty well too and there're also other devices in a similar price range you might wanna check.

 

[Irrenarzt]

I assume you mean a low noise power supply for the Atom since the KTB runs off USB power?

 

[maxxevv]

I assume you mean a low noise power supply for the Atom since the KTB runs off USB power?

The Atom runs off its own AC power plug, you con't find a cheap off-the-shelf replacement that's actually better than what is supplied.
The KTB can benefit from a separate 5V power supply but its not necessary in most cases unless your USB supply is truly and badly broken in terms of noise.

 

[Irrenarzt]

I'll try it as is first before worrying about any of that. Thanks for the recs. If it sounds good and clean, then no need to spend extra on stuff like that.

 

[magicscreen]

I have not used my Atom for two weeks approx.
How many hours I need to burn-in the Atom again? It has become "burned-out"
I have heard about burning-in a new amplifier, but this is something new.

 

[gustavjung]

Hi! Now I am using Behringer UCA222 as a DAC/AMP for my Senheiser HD 598SE and there is enough volume for me.
Will buying Atom amp or new D10+Atom improve listening experience significantly (details, sound stage)?

 

[solderdude]

When you need more connectivity or higher than 48kHz you need something to replace the UCA222.
Or when you plan to buy a better headphone or want to go a bit louder without the sound getting harsh.
Consider the UCA222 is the cheapest Behringer offering and does not test well.

 

[Toroid]

Listening to a D10+Atom right this moment. It is bloody fantastic and is loads better than the Schiit Fulla 2. When I go back and listen to the Schiit I can tell there is detail lacking. My cans ATM are the Senn PC37X, but I have some 6XX on the way

 

[thomasjast]

Listening to a D10+Atom right this moment. It is bloody fantastic and is loads better than the Schiit Fulla 2. When I go back and listen to the Schiit I can tell there is detail lacking. My cans ATM are the Senn PC37X, but I have some 6XX on the way

Atom + 6XX is a heavenly combination. Enjoy!

 

[magicscreen]

Could the volume pot cause sound quality issues?
For example:
At 9 o'clock the SQ is okay.
At 10 o'clock somehow the SQ is degraded, missing bass etc
At 11 o'clock the SQ okay.
There is no any noise, scratching from the pot.

Is this possible?

Or only in my brain
I am testing it now leaving at 9 o'clock and not turning off. Plugging it off instead.