Need advice on JDS Atom Headphone Amp - Low Volume

matty00721

Standard Member
Joined
Jan 3, 2019
Messages
21
Reaction score
3
Points
3
Age
31
Location
haverhill
Hi everyone,

So I recently purchased a JDS Atom in hopes of it replacing my space hoarding NAD 7125 vintage receiver. I only use it as a headphone amp to listen to my vinyl setup. Everything I have read has said the ATOM is a very powerful amp which should power anything out there. However, I have had a different experience

I used my DT 880 (600 ohm) cans to test it and was shocked at how low powered it is. Even on high gain, I have to turn it pretty much all the way up to get what I would consider satisfactory volume. I will admit that I like my cans pretty loud, but nothing ear splitting. With the same cans, I only have to turn my NAD 7125 to about 10 o clock, not even half way, for it to be decently loud. As said, with this Atom amp, it’s nearly all the way. On low gain? Forget it.

Now, I even tried it with the 32 ohm Fidelio X2’s, and while acceptably loud, I’m still having to turn it to 2 o clock to get my usual volume.

This just seems such disappointing performance to me, and my Nad stomps all over this. I’m thinking that I’m either nearly deaf, or there’s something else going on here.

Can anyone help me out? Thanks
 
I do not see why this would be looking at the spec list. Have you changed from low gain to high gain?
 
1 - does your turntable have a built in phono pre-amp?

2 - if it doesn't are you running it into a phono pre-amp to get a proper line level signal to feed the Atom?

The Atom is insanely powerful and you should be getting very loud levels through 600 Ohm beyers on low gain, if you are feeding it a proper line level signal.
 
1 - does your turntable have a built in phono pre-amp?

2 - if it doesn't are you running it into a phono pre-amp to get a proper line level signal to feed the Atom?

The Atom is insanely powerful and you should be getting very loud levels through 600 Ohm beyers on low gain, if you are feeding it a proper line level signal.

Hi,

I’m using a Pioneer PLX 1000 going through to a DJ Art Pre II phono stage, then into the Atom. To get decent volume I have to set it on high gain and crank it until it’s nearly at the max. On low gain it’s very very quiet indeed.

I get somewhat decent levels with the 32 ohm X2’s but it still needs high gain and about half way cranked.

I’m at odds as to why I’m getting such low power. Through my nad receiver I’m getting very loud volume, even if I go through the Art phono stage into the Nad aux ports, bypassing the NAD phono input. So the issue certainly appears to be the Atom amp.
 
Definitely using the input on the Atom and not the pre-out by accident?

I have use the Atom with a bunch of headphones and it gets incredibly loud.

You definitely have the gain trim on the DJ Art Pre II set to 0DB, and you are not using any splitters in the signal chain?
 
Definitely using the input on the Atom and not the pre-out by accident?

I have use the Atom with a bunch of headphones and it gets incredibly loud.

You definitely have the gain trim on the DJ Art Pre II set to 0DB, and you are not using any splitters in the signal chain?

Yes, it’s coming from the out on the DJ Pre to the RCA In on the Atom. Gain trim on the Art is set to 0, or even higher.

It’s really puzzling. Suppose the only thing I can try is my spare turntable with a built in pre to check if that improves things. But don’t think it will as the DJ Pre works fine going into the NAD

It’s really strange. I like my cans loud, but there is no way this amp should be this low powered. My Nad, and even my cheap SABAJ PH2 makes it seem like a Iphone jack in comparison
 
Yes, it’s coming from the out on the DJ Pre to the RCA In on the Atom. Gain trim on the Art is set to 0, or even higher.

It’s really puzzling. Suppose the only thing I can try is my spare turntable with a built in pre to check if that improves things. But don’t think it will as the DJ Pre works fine going into the NAD

It’s really strange. I like my cans loud, but there is no way this amp should be this low powered. My Nad, and even my cheap SABAJ PH2 makes it seem like a Iphone jack in comparison

Have you got any other sources your can put into the atom?

It definitely sounds like you have an issue, so you'll need to try different setups to find where the issue lies.
 
Have you got any other sources your can put into the atom?

It definitely sounds like you have an issue, so you'll need to try different setups to find where the issue lies.

I tried it with my old LP60 turntable with its built in preamp, and the issue is still there, in fact it’s even quieter.

Pretty much confirms the amp is faulty and I will return it. Not sure if whether to chance another one or get something different. Not that there’s anything in this price range with such raw power. I’d be happy to stick with the Nad but it’s very big and has a slight channel imbalance.

What are the chances of getting a faulty unit huh? Must be minuscule 😓. Couldn’t even find a thread related to this issue on the entire internet.
 
Okay, so as a last ditch test I connected it to a iPhone jack via the 3.5mm input. It needed high gain and about 12-1 o’clock on the 32ohm Fidelios to get to good volume.

With the DT 880’s (600 ohm) it needed high gain and nearly fully cranked to reach mediocre volume

Definitely something wrong with the amp. I’m just really hesitant to try another Atom amp.
 
Okay, so as a last ditch test I connected it to a iPhone jack via the 3.5mm input. It needed high gain and about 12-1 o’clock on the 32ohm Fidelios to get to good volume.

With the DT 880’s (600 ohm) it needed high gain and nearly fully cranked to reach mediocre volume

Definitely something wrong with the amp. I’m just really hesitant to try another Atom amp.

I would give another Atom a go, as they are truly superb and nothing beats them under £250 really.
 
Okay, so as a last ditch test I connected it to a iPhone jack via the 3.5mm input. It needed high gain and about 12-1 o’clock on the 32ohm Fidelios to get to good volume.
Certainly sounds faulty. High gain with 32ohm should blow your head off.
 
The knob on an amplifier does not dictate the actual volume. many older amplifiers volume knobs were not linear with most of the power coming before reaching 12 oclock.

In addition to this, older amplifiers inputs are more sensitive and so the voltage needed to get to max volume is a lot less.

Just because you have to turn the volume up on the atom, this does not mean it's faulty.

I would max the gain on the preamp as it's only 1.4v. the atom inputs will likely be ok upo to 2v
 
I just got my Atom today and I am experiencing the same thing. I have a very simple setup and I am still not getting the HUGE power people said that the atom has. I am using my macbook pro into RCA in and an Iphone in the 3.5mm in. For headphones, I am using Senn 58x which should be easy to drive and to get them loud I need to run the amp on high gain 3 o clock. Those are 150ohm headphones, I am not sure how can this amp drive the 300ohm 6xx I was planning on getting. Same experience with Senn Game Ones... High gain 3 o'clock they are loud. Low gain is kinda usable at max volume. The only headphones that get loud at 3 oclock with low gain are a crappy turtle beach elite pro gaming headsets. I have changed cables and everything and still the same. I have no idea if I need an external DAC to get the full power, if its normal for the amp and I was expecting more power, or simply a faulty Atom. Did you find a solution?
 
I just got my Atom today and I am experiencing the same thing. I have a very simple setup and I am still not getting the HUGE power people said that the atom has. I am using my macbook pro into RCA in and an Iphone in the 3.5mm in. For headphones, I am using Senn 58x which should be easy to drive and to get them loud I need to run the amp on high gain 3 o clock. Those are 150ohm headphones, I am not sure how can this amp drive the 300ohm 6xx I was planning on getting. Same experience with Senn Game Ones... High gain 3 o'clock they are loud. Low gain is kinda usable at max volume. The only headphones that get loud at 3 oclock with low gain are a crappy turtle beach elite pro gaming headsets. I have changed cables and everything and still the same. I have no idea if I need an external DAC to get the full power, if its normal for the amp and I was expecting more power, or simply a faulty Atom. Did you find a solution?

I tried to explain the the previous post.

There is more to headphones impedance that affects the volume. I have a 35ohm pair of headphones that need 2w of power to drive properly and this is due to their sensitivity which is 90db.

low gain drops the signal by 10db I believe and is designed to be used with sensitive iems so I’m not surprised you can max out the volume with harder to drive cans.

the volume jds advertise is from a 2v source level from a dac or in your case iPhone. You need to make sure the internal sound cards are turned up to maximum
 
I just got my Atom today and I am experiencing the same thing. I have a very simple setup and I am still not getting the HUGE power people said that the atom has. I am using my macbook pro into RCA in and an Iphone in the 3.5mm in. For headphones, I am using Senn 58x which should be easy to drive and to get them loud I need to run the amp on high gain 3 o clock. Those are 150ohm headphones, I am not sure how can this amp drive the 300ohm 6xx I was planning on getting. Same experience with Senn Game Ones... High gain 3 o'clock they are loud. Low gain is kinda usable at max volume. The only headphones that get loud at 3 oclock with low gain are a crappy turtle beach elite pro gaming headsets. I have changed cables and everything and still the same. I have no idea if I need an external DAC to get the full power, if its normal for the amp and I was expecting more power, or simply a faulty Atom. Did you find a solution?

Neither your phone, or your macbook output a true line-level signal, so it won't go as loud.

I would expect you would need high gain with both of those devices as the source.

The standard gain is 1x so perfect for use with 2v RMS DAC's as it is not adding gain, just power. High gain is 4.5x so it is adding gain and power, which is needed for less powerful sources like an iPhone or Macbook.

Low gain will not be louder than the source signal, it is adding power, not volume.
 
The knob on an amplifier does not dictate the actual volume. many older amplifiers volume knobs were not linear with most of the power coming before reaching 12 oclock.

In addition to this, older amplifiers inputs are more sensitive and so the voltage needed to get to max volume is a lot less.

Just because you have to turn the volume up on the atom, this does not mean it's faulty.

I would max the gain on the preamp as it's only 1.4v. the atom inputs will likely be ok upo to 2v

Thanks for your reply.

I understand what you are saying, but this is 100% faulty. Comparing this to a cheap SABAJ PH2 amp, it is no more powerful. In fact, my FX Audio X6 is actually more powerful with it’s changed jumpers.

I understand the difference between new and old amplifiers, but even on high gain and absolutely maxed out, this only gives mediocre volume with easy to drive DT 880’s. As another user said, this amp with 32 ohm fidelios should blow my head off, even on low gain. On mine, it needs high gain and 12 o clock. This is unacceptable.
 
The knob on an amplifier does not dictate the actual volume. many older amplifiers volume knobs were not linear with most of the power coming before reaching 12 oclock.

In addition to this, older amplifiers inputs are more sensitive and so the voltage needed to get to max volume is a lot less.

Just because you have to turn the volume up on the atom, this does not mean it's faulty.

I would max the gain on the preamp as it's only 1.4v. the atom inputs will likely be ok upo to 2v
Also, yes the preamp is 1.4v. But if I tried to max out the preamp, it will cause horrendous clipping.

I have seen many people using this with vinyl preamps which are typically 1.4v and having no issues

Having to turn up 880’s to max on high gain is totally unacceptable. There is no headroom and I can tell it’s not driving them properly.

Through my Nad amplifier they have plenty of headroom and sounds more full and bassy
 
Also, yes the preamp is 1.4v. But if I tried to max out the preamp, it will cause horrendous clipping.

I have seen many people using this with vinyl preamps which are typically 1.4v and having no issues

Having to turn up 880’s to max on high gain is totally unacceptable. There is no headroom and I can tell it’s not driving them properly.

Through my Nad amplifier they have plenty of headroom and sounds more full and bassy

the quoted figures of the atom are with a 2v input. if your preamp maxes out at 1.4v,

1) you will not get the quoted figures as per jds and

2) there should be no clipping with the atoms amplifier. If you are then there is clearly an issue with either the atom or the signal from the phono pre.

I was not stating that your atom was not faulty. i was just highlighting some reasons why it may not be performing to spec.

A lot of people seem to think a 1w amp will sound twice as loud as a 500mv amplifier when obviously this is not the case (far from it) and would need a 5w amplifier to achieve that goal. Also there's a lot of issues when it comes to matching gear, especially older gear with newer.

I myself have experienced this 1st hand. my own phono preamp plays a lot quieter compared to my newer dac, which matches its voltage output more in line with my amplifier.
 
the quoted figures of the atom are with a 2v input. if your preamp maxes out at 1.4v,

1) you will not get the quoted figures as per jds and

2) there should be no clipping with the atoms amplifier. If you are then there is clearly an issue with either the atom or the signal from the phono pre.

I was not stating that your atom was not faulty. i was just highlighting some reasons why it may not be performing to spec.

A lot of people seem to think a 1w amp will sound twice as loud as a 500mv amplifier when obviously this is not the case (far from it) and would need a 5w amplifier to achieve that goal. Also there's a lot of issues when it comes to matching gear, especially older gear with newer.

I myself have experienced this 1st hand. my own phono preamp plays a lot quieter compared to my newer dac, which matches its voltage output more in line with my amplifier.

No, on the DJ Pre ii there is a gain knob. If it is set to 0, it is at nominal volume and on new recordings, near clipping. If I turn it to + 6db, it will clip the signal. This is true with any device. There is nothing wrong with the turntable, or preamp.

Set at 0db, it’s very loud through both the nad receiver and my other receiver. There should be no need to max out the gain on the preamp and clip the signal.
 
No, on the DJ Pre ii there is a gain knob. If it is set to 0, it is at nominal volume and on new recordings, near clipping. If I turn it to + 6db, it will clip the signal. This is true with any device. There is nothing wrong with the turntable, or preamp.

Set at 0db, it’s very loud through both the nad receiver and my other receiver. There should be no need to max out the gain on the preamp and clip the signal.

This is probably due to your Nad and other receiver having much higher gain than the JDS Labs Atom (probably around 8x), and not actually to do with the power output. People get mixed up between power/gain.

You really do need to try this atom with a DAC that provides a real line-out, or CD player that does the same.

If your phono pre-amp only outputs 1.4v it is normal that you have to have it in high gain.


 
This is probably due to your Nad and other receiver having much higher gain than the JDS Labs Atom (probably around 8x), and not actually to do with the power output. People get mixed up between power/gain.

You really do need to try this atom with a DAC that provides a real line-out, or CD player that does the same.

If your phono pre-amp only outputs 1.4v it is normal that you have to have it in high gain.



Umm, interesting. Thanks.

Although surely, the Audio Technica table I have with a built in amp would maybe output at 2v?

I don’t have a CD player, but I do have a DAC. I will plug it in to that and see if it helps.

I was hoping that this Atom would be the end of me having to buy more gear for my vinyl rig. If what you say is true and the Atom is fine but being supplied too little voltage, I’m going to have to spend yet more money for another phono preamp. Finding one with 2v seems tough though.

The output currently is just too low. Yes, it just cuts it for my Fidelio’s, but it’s way too low for my 880’s. It needs to be maxed out. No headroom and I can hear it’s not being driven properly.
 
Last edited:
Okay, so I threw it into a DAC which is connected to my TV via optical. The DAC outputs at 2V.

There does seem to be an improvement but still not what I’d expect.

With the 880’s, it’s outputting at 55db ish on fully cranked on low gain.

On high gain, I am cranking it to 3 o clock to get what I would consider my ideal listening volume (meter says it’s outputting at 78db) This is somewhat loud, but not earsplitting nor damaging to ears. Fully cranked it is outputting at about 84db

This seems totally unacceptable with an amp that’s supposed to be very powerful. There is no headroom whatsoever and I’m getting very little dynamics
 
Last edited:
Okay, so I threw it into a DAC which is connected to my TV via optical. The DAC outputs at 2V.

There does seem to be an improvement but still not what I’d expect.

With the 880’s, it’s outputting at 55db ish on fully cranked on low gain.

On high gain, I am cranking it to 3 o clock to get what I would consider my ideal listening volume (meter says it’s outputting at 78db) This is somewhat loud, but not earsplitting nor damaging to ears. Fully cranked it is outputting at about 84db

This seems totally unacceptable with an amp that’s supposed to be very powerful. There is no headroom whatsoever and I’m getting very little dynamics

I am on the same boat as you man, I kinda like the atom and was going to buy a topping D50s to go with it but if you say that with your DAC it doesnt make huge improvement I think I am gonna pass. I am happy with it on high gain 3-4pm, but I was expecting a lot LOT more. Honestly, I can drive my headphones to the same loudness as high gain 3-4pm, straight from my macbook with EQ tweaks. I am still not sure if its the way it is or if its defective.
 
I am on the same boat as you man, I kinda like the atom and was going to buy a topping D50s to go with it but if you say that with your DAC it doesnt make huge improvement I think I am gonna pass. I am happy with it on high gain 3-4pm, but I was expecting a lot LOT more. Honestly, I can drive my headphones to the same loudness as high gain 3-4pm, straight from my macbook with EQ tweaks. I am still not sure if its the way it is or if its defective.

It is so strange isn’t it?!!.

Firstly I thought I may be going deaf. But by using a db meter I can see that I am certainly not. Perfect volume for me is just south of 80db which is pretty standard and should be WELL within the realms of possibility with even the most modest of outputs.

I keep thinking...is it me, or is it a defective unit?. I must say that I VERY rarely hear of this issue anywhere, at least once basic user oversights have been accounted. It is incredibly rare to get an amp that is working, but just outputting low. I could not find one other thread on the net where a dodgy Atom unit has been noted. It is made even more rare or seemingly impossible by the fact that each Atom unit is personally checked by someone prior to it leaving the factory.

So I keep thinking, it must be something I am doing wrong. I thought the useful insight from the previous post about a lacking voltage input would certainly be the cause, but I’m still getting modest low output from this thing with a 2v line level from a Dac

I mean yeah, sure, I could just live with it and crank it to nearly full to get decent volume, but it’s still mediocre at best, and my inner audiophile hates having no headroom and it just screams ‘struggling audio’. I can also hear a obvious lack of dynamics in my cans when powering it with the Atom as opposed to my vintage nad receiver. There is no fullness or punch whatsoever.

And yeah, it’s perfectly okay with 32ohm cans on high gain (really it should be low gain) but that rather seems a futile waste of money considering I could power them off pretty much anything. I only brought this amp to replace my massive receiver, save some space, and power my 880’s with ease.

Many many threads have stated that the Atom should power the 600 ohm 880’s with ease even on low gain, so what gives?

Maybe we both have a defective unit, but the odds must be minuscule, like lottery minuscule.

I am bemused, and very irritated
 
Last edited:
It is so strange isn’t it?!!.

Firstly I thought I may be going deaf. But by using a db meter I can see that I am certainly not. Perfect volume for me is just south of 80db which is pretty standard and should be WELL within the realms of possibility with even the most modest of outputs.

I keep thinking...is it me, or is it a defective unit?. I must say that I VERY rarely hear of this issue anywhere, at least once basic user oversights have been accounted. It is incredibly rare to get an amp that is working, but just outputting low. I could not find one other thread on the net where a dodgy Atom unit has been noted. It is made even more rare or seemingly impossible by the fact that each Atom unit is personally checked by someone prior to it leaving the factory.

So I keep thinking, it must be something I am doing wrong. I thought the useful insight from the previous post about a lacking voltage input would certainly be the cause, but I’m still getting modest low output from this thing with a 2v line level from a Dac

I mean yeah, sure, I could just live with it and crank it to nearly full to get decent volume, but it’s still mediocre at best, and my inner audiophile hates having no headroom and it just screams ‘struggling audio’. I can also hear a obvious lack of dynamics in my cans when powering it with the Atom as opposed to my vintage nad receiver. There is no fullness or punch whatsoever.

And yeah, it’s perfectly okay with 32ohm cans on high gain (really it should be low gain) but that rather seems a futile waste of money considering I could power them off pretty much anything. I only brought this amp to replace my massive receiver, save some space, and power my 880’s with ease.

Many many threads have stated that the Atom should power the 600 ohm 880’s with ease even on low gain, so what gives?

Maybe we both have a defective unit, but the odds must be minuscule, like lottery minuscule.

I am bemused, and very irritated

HAHA I feel you, I am still trying and playing with different settings and equipment. I was planning on buying Argons mk3 in a month or so, after people telling me that the atom can drive them quite nicely. But I am not sure about that. I guess I will get a DAC and try it, maybe I am becoming deaf? or use my headphones too loud? What is seriously very weird, is that I can output the same high gain power from my macbook tweaking the EQs. I thought that the atom would blow my low impedance high sensitivity IEMs but it clearly will not.
 

The latest video from AVForums

Is 4K Blu-ray Worth It?
Subscribe to our YouTube channel
Back
Top Bottom