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Review and Measurements of New JDS Labs Atom Headphone Amp

Veri

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Is atom a good amp for dt990 250ohm or is it OP?
Atom would be good, it's pretty much the best budget amp out there. It's not OP if you use low gain and only go high gain when necessary.

Do you need an amp, though :) you can try your Dt990 from your computer first and see if they are driven satisfactory :)
 
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Atom would be good, it's pretty much the best budget amp out there. It's not OP if you use low gain and only go high gain when necessary.

Do you need an amp, though :) you can try your Dt990 from your computer first and see if they are driven satisfactory :)
Alright, thank you :)
Yeah, using a fiio k3 atm but it's not enough.
 
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Is atom a good amp for dt990 250ohm or is it OP?
If you read the past two pages, starting with my post here, you'll see we were actually just discussing this (someone asked about DT 770, but I have DT 990 which is similarly hard-to-drive, so I gave my thoughts).

Others say you can run in low gain, but I don't agree. My experience is you'd need the Atom's full muscle at high gain to power DT 990 properly. I have a DX3 Pro currently which does 125mW into 300 Ohms, that works but I have no headroom for really quiet tracks, like in some movies, etc.

Your FiiO K3 has 13mW of power into 300 Ohms according to Amir's measurements, which I'd say is nowhere near enough for 250 Ohm DT 990. If you're thinking it's enough (not sure if that was a typo or not in your last post), then you'll definitely be impressed with the Atom, especially in how much more bass/lowend you'll get, as I can guarantee that those headphones are being starved for power at a measly 13mW.
 
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If you read the past two pages, starting with my post here, you'll see we were actually just discussing this (someone asked about DT 770, but I have DT 990 which is similarly hard-to-drive, so I gave my thoughts).

Others say you can run in low gain, but I don't agree. My experience is you'd need the Atom's full muscle at high gain to power DT 990 properly. I have a DX3 Pro currently which does 125mW into 300 Ohms, that works but I have no headroom for really quiet tracks, like in some movies, etc.

Your FiiO K3 has 13mW of power into 300 Ohms according to Amir's measurements, which I'd say is nowhere near enough for 250 Ohm DT 990. If you're thinking it's enough (not sure if that was a typo or not in your last post), then you'll definitely be impressed with the Atom, especially in how much more bass/lowend you'll get, as I can guarantee that those headphones are being starved for power at a measly 13mW.
Okay, the plan atm is to use the k3 as dac for now and get another one later on maybe a D10 or D30?
Sorry it was a typo :facepalm: Just bought the 990 and yes the k3 cant handle them at all.
Thanks! :)
 
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Okay, the plan atm is to use the k3 as dac for now and get another one later on maybe a D10 or D30?
Seems like a good plan to me. In my case I plan to eventually get a better amp for my DT 990s, and use the DX3 as a DAC, although since the DX3 is pretty good I likely won't really need an upgrade down the line. The reason I haven't gotten an Atom yet is that I'm a bit of a stickler when it comes to having a metal chassis.

I'm going to wait until Q4 to see some new products coming out towards the end of the year, and then decide what to get then.

In your case, an interesting option might be the Grace SDAC Balanced which has recently been reviewed here, it's mostly for balanced output, but it does have unbalanced output also, so if you ever upgrade to a balanced setup you won't need to switch to a different DAC, so it has a bit of "future-proofedness" to it. Given it's low price, you wouldn't be paying much more for it.
 
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Seems like a good plan to me. In my case I plan to eventually get a better amp for my DT 990s, and use the DX3 as a DAC, although since the DX3 is pretty good I likely won't really need an upgrade down the line. The reason I haven't gotten an Atom yet is that I'm a bit of a stickler when it comes to having a metal chassis.

I'm going to wait until Q4 to see some new products coming out towards the end of the year, and then decide what to get then.

In your case, an interesting option might be the Grace SDAC Balanced which has recently been reviewed here, it's mostly for balanced output, but it does have unbalanced output also, so if you ever upgrade to a balanced setup you won't need to switch to a different DAC, so it has a bit of "future-proofedness" to it. Given it's low price, you wouldn't be paying much more for it.
Same here, love the D30+A30 combo look :)
Do you the A30 is enough for the 990? It’s cheaper here in EU or is it worth the extra to get the atom.
Alright, thanks for the tip and all help :)
 
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Do you the A30 is enough for the 990? It’s cheaper here in EU or is it worth the extra to get the atom.
It's hard to say, according to Amir's measurements it has 180mW of power at 300 Ohms, which is definitely more than my DX3 Pro, but is quite a bit lower than the Atom's 250mW. It also seems to have a high output impedance, which isn't good.

It will certainly be way better than what you have now, but I would still recommend the Atom, honestly.
 

amirm

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It's hard to say, according to Amir's measurements it has 180mW of power at 300 Ohms, which is definitely more than my DX3 Pro, but is quite a bit lower than the Atom's 250mW. It also seems to have a high output impedance, which isn't good.

It will certainly be way better than what you have now, but I would still recommend the Atom, honestly.
Okay, thank you! :)
 

Johnb

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I haven't checked all the pages so I dunno if there is a graph that compares low and high gain, but it's generally understood that for the Atom, you get no additional audible distortion at high gain. If you measured it however, it would probably be a bit higher on the graph for high than low gain, but again, this shouldn't be audible at all. The Atom is regarded to be one of the cleanest amps out there, in the same league as THX AAA 789.

The main purpose of the switch is that different headphones need different amounts of power to drive; on a sensitive headphone, the high gain would be way too strong and the volume knob would therefore be somewhat annoying to use as you'd only ever have it slightly turned up and it would already be too loud. So the gain switch lets you deal with that by giving you different settings for hard to drive vs easy to drive headphones.

I'm pretty sure the 250 Ohm DT 770s are difficult to drive; slightly easier than my 250 Ohm DT 990s which are the open-back version of the 770s, but still. These seem to be pretty difficult to power, my DX3 Pro just barely gets my 990s to a comfortable listening level at high gain, but with zero headroom for quiet tracks; I'm definitely going to need a better amp in future for them. =)

(FYI, the DX3 in high gain has about half the power as Atom in high gain, if you're curious for comparison purposes)
The advice is solid, but if you are interested, Amir did a study of Sinad with high and low gain: https://www.audiosciencereview.com/...s/study-headphone-amp-gains-low-or-high.5495/

Also, assuming a healthy 2V output on good dacs, many people might get "sufficient" loudness on 300 ohm can, but just barely, with unity gain. Everyone tries to get by with unity gain, if possible. I'll bet most people end up using high gain. I wish that amps came with 1.3x "low" gain position.
 
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The advice is solid, but if you are interested, Amir did a study of Sinad with high and low gain: https://www.audiosciencereview.com/...s/study-headphone-amp-gains-low-or-high.5495/
If you keep reading the thread onto the next page after I made that post, someone else mentioned the gain study and I managed to find that thread and I mentioned it here. The problem is it doesn't give you the Atom's headphone output levels (Distortion vs Power @ 300 Ohms graph, specifically), so while I know that the Atom outputs 250mW into 300 at high gain, I don't know what it outputs in low.

Also, assuming a healthy 2V output on good dacs, many people might get "sufficient" loudness on 300 ohm can, but just barely, with unity gain. Everyone tries to get by with unity gain, if possible. I'll bet most people end up using high gain. I wish that amps came with 1.3x "low" gain position.
It's not just about the impedance, it's about sensitivity, for instance, the AKG K712 is low impedance, but it's super insensitive and requires a lot of power, although typically the higher impedance cans are usually also more power hungry, but what this means is you can have two 250 Ohm Beyerdynamic cans like the DT 1770 vs the DT 770, but the latter requires a lot more power once you look up it's specs and use the digizoid power calculator to get it's power requirements (which will be at the impedance in question, which makes it tricky to directly compare the power requirements between cans that have different impedances).

As I've been saying for a few pages now, I own the DT 990s, and I need to set my DX3 Pro to high gain to get high volume, but I still have no headroom. I have no idea how much power the Atom puts out in low gain, but if it's close to what DX3 does in high (125mW @ 300 Ohm or so), then it's not enough unless you want no headroom for quiet tracks.

Also, in that very thread about the gain study, there's a post from solderdude that suggests that for insensitive cans you're not going to be able to hear any audible distortion on high gain, so it seems to me like the right setting for such hard to drive cans.
 
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So, I bought the Atom and I am using it with the SMSL SU-8 (Atom also being the pre-amp for my 305Ps). I have the SU-8 at almost full volume and I am using Atom's knob to adjust the volume. Is it normal that I need to have the Atom at high gain to get some decent volume on my HD580s?
 

maxxevv

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So, I bought the Atom and I am using it with the SMSL SU-8 (Atom also being the pre-amp for my 305Ps). I have the SU-8 at almost full volume and I am using Atom's knob to adjust the volume. Is it normal that I need to have the Atom at high gain to get some decent volume on my HD580s?
Your 305P's can be connected via the XLR or RCA output of the SU-8 directly, no need to go through the Atom.

As for the HD580, I'm not sure if you need the high gain for the them on the Atom. Unless you're running your SU-8 at very low output settings ?
I run my Khadas Tone Board at maximum digital (Foobar) volume output to my Atom. Listening to the HD6XX on them sounds plenty loud on low gain. Maybe you can toy around a bit between the SU-8 and the digital volume output from your music player?
 

Veri

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So, I bought the Atom and I am using it with the SMSL SU-8 (Atom also being the pre-amp for my 305Ps). I have the SU-8 at almost full volume and I am using Atom's knob to adjust the volume. Is it normal that I need to have the Atom at high gain to get some decent volume on my HD580s?
Going by 2V output from SU-8, unity gain should already be "loud"...
 
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Your 305P's can be connected via the XLR or RCA output of the SU-8 directly, no need to go through the Atom.

As for the HD580, I'm not sure if you need the high gain for the them on the Atom. Unless you're running your SU-8 at very low output settings ?
I run my Khadas Tone Board at maximum digital (Foobar) volume output to my Atom. Listening to the HD6XX on them sounds plenty loud on low gain. Maybe you can toy around a bit between the SU-8 and the digital volume output from your music player?
Well, going to the 305Ps directly from the SU-8 means I need to switch off the speakers any time I use the headphones. Not very convenient...
I am using MusicBee at full volume, and the SU-8 at volume 36 (out of 38).
 

solderdude

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It's hard to say, according to Amir's measurements it has 180mW of power at 300 Ohms, which is definitely more than my DX3 Pro, but is quite a bit lower than the Atom's 250mW. It also seems to have a high output impedance, which isn't good.

It will certainly be way better than what you have now, but I would still recommend the Atom, honestly.
The level difference is merely 1.4dB (250mW vs 180mW). The 10 Ohm output R is not a problem for 250 Ohm headphones, the tonal balance will not change audibly. It could be with some low impedance headphones for sure.

I agree with the Atom recommendation unless you like the stack or don't like the plastic feel of the Atom.
 
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