JDS Labs Atom Phono - love but 1 issue

[elshaddai]

I just wish they made a suitable power amp I could pair with the Atom - perhaps that will come in time. Thanks to all for the help!

Would love that option as well and/or a more versatile HP preamp with switchable speaker/sub outputs (rather than having to unplug the headphones). When I asked John about that previously, he gave the impression that they use powered speakers, so power amps aren't part of their normal signal chain. For now I've paired my Atom 2 DAC/HPA with a Buckeye power amp and they work very well together. That's another great company with local support and service.

 

[WDeranged]

I have a similar situation with my turntable, and have eliminated nearly all the noise by running a ground wire from the phono preamp ground terminal to a ground connection in an electrical socket.

If you do this take great care to ensure you are connecting to ground and not live or neutral. I removed the live/neutral pins on the plug to be sure - we can do that in the UK.

View attachment 411251

I have to do something similar with my Rega turntable.

 

[Joe Smith]

Replacement unit arrived today and simply swapping the original for the replacement immediately solved the problems. Just to make sure I wasn't crazy I went ahead and swapped back to the original and the problem was immediately audible even at moderate listening levels. Very glad this problem resolved itself. I'm still eager to have more time with the Atom and have a more realistic comparison with the Pluto 2. Can't say enough good things about communicating w/ John @ JDS - one of the main reasons I prefer to spend a bit more and work with a small company based here - the human connection is very much appreciated. I just wish they made a suitable power amp I could pair with the Atom - perhaps that will come in time. Thanks to all for the help!

I recently bought a Schiit Gjallarhorn amp and can recommend that to you. Also bought their new Saga 2 preamp. Both of these are nice products for the $ if you don't need a ton of power. I wonder if JDS will ever make a speaker amp, I love their products but this certainly does not seem to be anything they are hurrying to do.

 

[DA Roadie]

They really are. The only reason I've considered selling my Atom Phono is I recently got an amp with built in phono stage that sounds quite nice, albeit not as nuanced/detailed as the Atom. It's something I can notice slightly (I believe) A/B in non controlled settings but not sure I would notice long term without it. It's such a nice piece of equipment that I don't want to see it go. I wish they made more equipment aimed at analog folks as my digital equipment needs are pretty minimal.

I may well be pulling the trigger on the Atom 2 stack in the next few days and wondered if you could answer a connection question? I’ll be using the stack as (pretty much) a standalone headphone amps and dac to use with some Hifiman Arya Stealths. If that’s all I do, I’ll just get the Atom 2 and the Atom 2 Dac. What I thought might be great (if I can get my head round the connections) is to have a set up which lets me listen to vinyl on headphones and (when not doing that) continue listening to vinyl through my integrated amplifier (Electrocampionet ECI 6DX MK II) which, sadly, does not have a headphone jack or a means of A/B switching my main speakers when listening to headphones - hence the reason I cannot connect the Atom stack to the integrated. I wanted to double check that I can listen to vinyl through headphones and then, if I want to, bypass the headphone set up with an RCA connection to my integrated through the Atom Phono stage. I’m not sure whether this would mean running the Atom Phono in bypass mode. I already have a phone stage that I’m happy with (Cambridge Audio Alva MM) so getting the Atom Phono would be part aesthetics (neatness of the stack) and part the bypass function (if I need that). I think it would be Rega Planar 3 RCA into Atom Phono - RCA from Atom Phono to Atom Amp (for headphone listening) and then RCA from Atom 2 amp to ECI 6DX AUX in. Is that correct and possible? What would the switches of the Atom Phono stage do? Would the whole Atom stack need to be switched on when listening to vinyl on the room speakers? Is there a way of setting it up so only the Atom Phono stage needs to be on when listening on speakers? Sorry for the basic question, I’m not sure I fully understand the difference between a phono stage and a pre amp.

 

[ccrnnr9@]

I don't really understand what you're trying to do but a phono stage elevates the signal of a turntable to be at a more normal level when received by the amplifier. In short you'll need a phono stage to play records (whether as a phono pre-amp like the atom phono or as an integrated phono stage in a receiver/amp). I don't know a lick about headphone amps or listening to music through headphones. JDS does a lot of headphone amplified products and seems to be geared towards folks running powered speakers/headphones.

 

[Balle Clorin]

You don't want to MOVE the existing ground wire from the turntable, but rather ADD a second ground wire from the receptacle cover plate screw to the same lug.

What you're missing is any true Earth connection, because all your gear uses DC power supplies.

Your u have misunderstood. No need for connection to mother Earth, or safety ground. safety grounding does not need to becthe same as signals fregerencecground. My Sony TT and Cambridge RIAA have no connection to earth/receptacle ground. Simple 2prong and a wall wart in the Cambridge- “standard ground wire between TT and Cambridge RIAa .

 

[Balle Clorin]

Is the JDS phono placed close to any other component with a transformer? Phono/Riaa amps can pickup hum from wires and other components, try moving it around.

 

[antcollinet]

Your u have misunderstood. No need for connection to mother Earth, or safety ground. safety grounding does not need to becthe same as signals fregerencecground. My Sony TT and Cambridge RIAA have no connection to earth/receptacle ground. Simple 2prong and a wall wart in the Cambridge- “standard ground wire between TT and Cambridge RIAa .

On the other hand the only way to eliminate significant hum on my ungrounded turntable-waxwing-toslink-AVR was to run a ground wire from the waxwing to mains earth.

Not needed in all cases, but sometimes noise currents need a way to go to ground if they are not to get added to the signal. It is very much specific to the actual system and local environment.

See :

Fosi Audio V3 Amplifier Review

I'm pretty sure the knob controls volume, Matt.

audiosciencereview.com

 

[cgallery]

Your u have misunderstood. No need for connection to mother Earth, or safety ground. safety grounding does not need to becthe same as signals fregerencecground. My Sony TT and Cambridge RIAA have no connection to earth/receptacle ground. Simple 2prong and a wall wart in the Cambridge- “standard ground wire between TT and Cambridge RIAa .

Vinyl systems where all devices are powered via wall warts tend to suffer a lot of hum/noise until a low-resistance path to ground is provided.

 

[Balle Clorin]

?
what ground?
I have 4 turntables and 2 RIAAs , as long my as each TT is wired with the standard “ground” wire to RIAA everything is dead silent. Still trying to understand why the “ground”wire is required.
Michell gyro SME V.
Denon 51F, 21F
Sony PS- 212’
Parks Audio, Cambridge CP2.
AT OC9 33PTG Shure V15-I AT95E, OM10
All dead silent, but why?

 

[cgallery]

?
what ground?
I have 4 turntables and 2 RIAAs , as long my as each TT is wired with the standard “ground” wire to RIAA everything is dead silent. Still trying to understand why the “ground”wire is required.
Michell gyro SME V.
Denon 51F, 21F
Sony PS- 212’
Parks Audio, Cambridge CP2.
AT OC9 33PTG Shure V15-I AT95E, OM10
All dead silent, but why?

Likely because your preamplifier or integrated amplifier or whatever, provides that path via the RCA shields.

 

[Balle Clorin]

I did not express myself well, I do use the separate ground wire. but still missing a schematic that explains why it is needed..

 

[antcollinet]

I do use the separate ground wire

Which one? the one from Turntable to preamp, or from preamp to ground?

Doesn't really matter though - the answer in both cases is common mode noise. This can be picked up by stray electro-magnetic fields from nearby kit, or capacitively coupled in from the mains or or or.

If it doesn't have a good path to earth, then it will try to find a way through your analogue interconnect - and thereby get added to the signal.

 

[Balle Clorin]

Turntable has 3 wires L R and Ground. Ground goes to RIAA ground lug, and from there another Ground wire is going to preamp Ground lug- and also RCA L and R. L and R balanced RCA to power amp - no ground wire there. If ground wire RIAA to amp becomes loose it hums like hell. I read Bill Whitlock papers on grounding , without fully grasping why RIAA cannot be hum free without the 3rd ground wire , other sources don’t need it. Riaa has wall wert without grounding pin, All pre and power has 3 pin prong.
M
I notice Whitlock explanation and diagram in how noise goes via RCA shield on RCA , what is not so clear to me is how the noise is created in the first place. The cartridge is “floating” with out any other electrical stuff/parts.

Is it just airborne magnetic and electric noise? The AC 50hz is “everywhere “?

https://www.aes.org/standards/webinars/AES_Standards_Webinar_SC0505_20210726.pdf

 

[antcollinet]

without fully grasping why RIAA cannot be hum free without the 3rd ground wire , other sources don’t need it.

One reason for this is your RIAA preamp has around 40db of gain (or more) which means any noised picked up on the turntable and its interconnect and delivered to the RIAA pre gets amplified x100 before going to your pre/power amp.

Is it just airborne magnetic and electric noise? The AC 50hz is “everywhere “?

Sort of. Every wire in your system has a magnetic (EDIT : and electrostatic caused by voltage which can couple capacitively) field around it caused by the current through it. Power transformers (eg in your power amp) have much larger stray magnetic fields around them. These fields can couple into any other conductor via magnetic induction. The amount of coupling will depend on how close the source and destination conductors are to each other - as well as how they are physically arranged (eg if creating a large loop area).

Consider also common mode noise on the mains (say going into your wall warts). This can be noise appearing on both the live and neutral wires simultaneously with respect to earth. This can couple capacitively or inductively onto the chassis of your turntable or preamp.

If there is no wire to real earth, for these noise currents, then they will try to find another path to earth through the shield of your analogue interconnect. As shown in the diagrams you reference above.

There are other sources of noise also. Good grounding is essential to minimising their impact on the sound.

 

[Balle Clorin]

I better get a fatter ground wire then..