Review and Measurements of New JDS Labs Atom Headphone Amp

[maxxevv]

Tastes and preferences differ perhaps ?
What's 'better' for person A may be 'worse' for person B.

Truth.

I tried the Utopia, Stellia, Arya, HD800, HD800s, SR1a, Aeon (open and close), Verum, Stax 009.

Personally 'most agrreable' sounding being the Arya and the SR1a. Then the HD800.

 

[AndrovichIV]

Perhaps dumb question. Say I have HD-600's (300 ohm). Is it better to play them on low or high gain on this amp?

If I understand correctly low gain is cleaner, but in high there's more power "to tame the headphones". On low gain I don't go further than 2pm on the dial.

 

[ngs428]

Perhaps dumb question. Say I have HD-600's (300 ohm). Is it better to play them on low or high gain on this amp?

If I understand correctly low gain is cleaner, but in high there's more power "to tame the headphones". On low gain I don't go further than 2pm on the dial.

In general, stay on low gain unless you can’t drive them to a sufficient level. Sounds like you need to stay on low gain. I do too with my HD 6XX

 

[JohnYang1997]

In general, stay on low gain unless you can’t drive them to a sufficient level. Sounds like you need to stay on low gain. I do too with my HD 6XX

Use lowest gain possible as long as it's loud enough.

 

[Crane]

Use lowest gain possible as long as it's loud enough.

This would actually be interesting to see the measurement difference between the two gain settings at similar levels, if that is possible.

 

[maxxevv]

Perhaps dumb question. Say I have HD-600's (300 ohm). Is it better to play them on low or high gain on this amp?

If I understand correctly low gain is cleaner, but in high there's more power "to tame the headphones". On low gain I don't go further than 2pm on the dial.

I drive the HD6XX / 650 which is marginally more efficient than the HD600 on my Atom, volume pot was only at 12 o'clock ( occasionally slightly higher) at low gain. Source was a Khadas Tone Board at 100% digital volume.

And that's as high as I would go if it were to be a sustained listening session.

 

[JohnYang1997]

This would actually be interesting to see the measurement difference between the two gain settings at similar levels, if that is possible.

Less gain = more feedback = lower distortion and noise (in general)
Except when it's inverting amplifier.
Also there are measurements here from amirm showed lower noise and distortion when using low gain in the first few posts.

 

[AndrovichIV]

Okay, next question then. How do I know that at my current listening level my headphones are getting an adequate amount of power (are not underpowered)?

The way I see it, if low gain pushes my headphones loud enough _and_ is cleaner _and_ they have the power they need, then I should be using low gain.

 

[JohnYang1997]

Okay, next question then. How do I know that at my current listening level my headphones are getting an adequate amount of power (are not underpowered)?

The way I see it, if low gain pushes my headphones loud enough _and_ is cleaner _and_ they have the power they need, then I should be using low gain.

Basically that's how it happens. One thing to understand is that using low gain doesn't change the physical limitation of the amplifier such as supply rail/ voltage swing and current output capacity, it's just less gain/less loud. If you can give "loud" enough input signal the same loudness can be achieved.

 

[pevzi]

I'm considering getting Atom and Verum 1, but I'm a bit concerned about their low impedance, which is said to be just 8 Ohm. If I understand it correctly, it means that they're very current-hungry and may pair poorly with some amps (to the point of the amp shutting down at high volumes). Does anyone know firsthand if Atom is mighty enough to power them without audible distortion? Perhaps @amirm has done some low-impedance load measurements?

 

[JohnYang1997]

I'm considering getting Atom and Verum 1, but I'm a bit concerned about their low impedance, which is said to be just 8 Ohm. If I understand it correctly, it means that they're very current-hungry and may pair poorly with some amps (to the point of the amp shutting down at high volumes). Does anyone know firsthand if Atom is mighty enough to power them without audible distortion? Perhaps @amirm has done some low-impedance load measurements?

Atom will have a big increase in distortion with 8 ohm loading, it's more severe at high frequency. However, at normal level it still shouldn't exceed 0.01% under 6khz. I doubt you can get audible distortion.
One thing to acknowledge is that I haven't seen an headphone amp on the market is able to have superb performance at 8ohm load. Thx789 possibly but haven't tested yet and it's not recommended by thx.
Also, I personally recommend look for a different headphone like hd58x, sundara. If you have heard Verum yourself from friends and you really like it, go ahead.

 

[pevzi]

Atom will have a big increase in distortion with 8 ohm loading, it's more severe at high frequency. However, at normal level it still shouldn't exceed 0.01% under 6khz. I doubt you can get audible distortion.

0.01% is still pretty good I guess, thanks.

Also, I personally recommend look for a different headphone like hd58x, sundara. If you have heard Verum yourself from friends and you really like it, go ahead.

Sadly, no, I haven't heard any of them, so I have to rely on subjective descriptions from audiophiles. Sundara was another headphone I was considering actually, but after watching/reading some reviews I've come to a conclusion that Verum 1 should sound more to my liking. Sundara does look better though.

 

[JohnYang1997]

I'm considering getting Atom and Verum 1, but I'm a bit concerned about their low impedance, which is said to be just 8 Ohm. If I understand it correctly, it means that they're very current-hungry and may pair poorly with some amps (to the point of the amp shutting down at high volumes). Does anyone know firsthand if Atom is mighty enough to power them without audible distortion? Perhaps @amirm has done some low-impedance load measurements?

 

[solderdude]

Ken Rockwell measured the impedance (resistance) to be 6 Ohm.
I find this to be rather low but there are IEM's that dip even lower.
In that case though much less power is drawn because of their higher efficiency and the impedance dropping this low in a narrow frequency band only.

Looks like the Atom won't have much trouble driving them.

 

[Veri]

I'm considering getting Atom and Verum 1, but I'm a bit concerned about their low impedance, which is said to be just 8 Ohm. If I understand it correctly, it means that they're very current-hungry and may pair poorly with some amps (to the point of the amp shutting down at high volumes). Does anyone know firsthand if Atom is mighty enough to power them without audible distortion? Perhaps @amirm has done some low-impedance load measurements?

Atom will be fine especially for the $99, consider it ever breaking because of continuous power draw. It will not break the bank replacing one in few years if that would be necessary. The THX AAA is also 'not recommended' for use with 8ohm headphone, so if that one would break it would hurt much more, not even mentioning the LOW availability of said amp.

 

[AresHarvest]

There are also inline attenuators like IEMatch that come in handy with Verum or other low-impedance and/or high-sensitivity headphones. Helps to avoid the channel imbalance at low volume positions when you have really efficient headphones, and in the case of the IEMatch it presents a load of (I think) 16Ω to the amp.

Of course, the IEMatch costs as much as the Atom, but I think it would be worth it if you're using the Verum with different sources. Just consider it part of the cost of that headphone. I'm pretty close to getting one for use with my CCA C16 (27Ω, 105 dB/mW) because they're just too sensitive.

 

[solderdude]

When you are handy with a soldering iron

 

[AresHarvest]

For sure, I would only have to order some resistors, as I already have everything else. Or maybe I'll just be lazy and get the EarBuddy for $20

 

[riya]

Objectively speaking (from measurements) what gain does "sound" better? Low Gain seems to have better SINAD but has noticeably less SNR. I'm quite new to all of this, so sorry in advance if that's a stupid question to ask. I can run my headphones (beyerdynamic Amiron Home) in both gain modes comfortably and wondered which gain to pick to get the best sound quality.

After doing some testing switching between both of them it feels like High Gain makes the vocals sound a tad clearer in comparison. But that may as well be some sort of placebo effect.

Thanks in advance and thanks for providing this awesome forum completely for free!

 

[SimpleTheater]

Thanks in advance and thanks for providing this awesome forum completely for free!

You can contribute voluntarily. I’m a new member, but I’m already so blown away with the detail and hard work that amirm puts into this site that I contributed $25 today. Just go to Account Details and click on Account Upgrades.