JS-2 Power Supply

[ikemi]

Hey Guys,

 

I’m thinking about pulling the trigger on a JS-2 to power my etherregen. Can anyone with a JS-2 powering an etherregen comment on what improvements if any I might hear. Also another 2 questions: 1) I also want to power another component that will be on the A side of the etherregen—-can I power both the etherregen and the A side component from the same JS-2 power supply without detrimental effects? 2) is the JS-2 a floating design such that I would need to ground the etherregen (I will have more than one connection to the A side of etherregen)? 

Thanks in advance for your help guys!!

 

Ron

[JohnSwenson]

Yes, powering the EtherREGEN and an A side device from the same JS-2 is fine

On 3/25/2020 at 3:12 PM, ikemi said:

Hey Guys,

 

I’m thinking about pulling the trigger on a JS-2 to power my etherregen. Can anyone with a JS-2 powering an etherregen comment on what improvements if any I might hear. Also another 2 questions: 1) I also want to power another component that will be on the A side of the etherregen—-can I power both the etherregen and the A side component from the same JS-2 power supply without detrimental effects? 2) is the JS-2 a floating design such that I would need to ground the etherregen (I will have more than one connection to the A side of etherregen)? 

Thanks in advance for your help guys!!

 

Ron

Yes, powering an EtherREGEN and an A side device from the same JS-2 is fine. The JS-2 negative outputs are isolated from the Safety ground on the AC power cord. You might want to try grounding the "ground screw" on the EtherREGEN ans see if it makes any difference.

 

John S.

[ikemi]

Thank you JS for the quick reply—— much appreciated. I have another question for you if you don’t mind. Many people on this form talk about using one linear power supply to power another linear power supply. How does that work and what are the benefits if any of going that? Could doing that in some way improve sound quality? Thanks in advance for considering my questions!!

 

Ron

[Superdad]

5 hours ago, ikemi said:

Many people on this form talk about using one linear power supply to power another linear power supply. How does that work and what are the benefits if any of going that? 

 

Hi Ron:

Well the JS-2 is a full AC>DC dual-output, choke-filtered, 5-7.4 amp linear power supply.  One can not power it with some other LPS.

 

However, there are some DC>DC power supplies (including a somewhat popular DIY board brand) which take DC in at one voltage (just about the target output voltage) and run that though low-noise regulators to then output DC.

 

And then there is the unique case of our own UltraCap LPS-1.2, which must be "energized"/charged from an external DC supply. With that model we include a customized 36W SMPS as charger. We do not think there is any benefit to charging the UltraCap LPS-1.2 from a linear supply. [If you study the design of our UltraCap model, you will see that the bank of capacitors connected to the cascaded and paralleled ultra-low-noise output voltage regulators at any given moment are disconnected from the charging power domain. The other bank is being charged at that moment--and then we alternate.]

 

I hope the above information is helpful to you.  And welcome to the Audiophile Style forums!

--Alex C.

[davide256]

@Superdad   I like the Linear Tube Audio MZ2 I have, it performs amazingly well as a 1 watt class A amp with my Magnepan 1.7 speakers using the JS-2 for DC power supply. I'm thinking of pairing the MZ2 with their Zotl 10MkII amplifier as I think that would give me the added db's I need but would prefer to use

(trust) a JS-2 instead of their LPS for stablity under full PS load. Can a JS-2 be configured to support this?

 

"The ZOTL10 comes with a power supply that supplies 10A of 24V. "

 

[miguelito]

On 3/25/2020 at 6:12 PM, ikemi said:

I’m thinking about pulling the trigger on a JS-2 to power my etherregen. Can anyone with a JS-2 powering an etherregen

Why not an Ultracap 1.2? 

[davide256]

10 minutes ago, miguelito said:

Why not an Ultracap 1.2? 

Agree, right tool for the job. Save the JS-2 for current hungry beasts ;<)

[Superdad]

40 minutes ago, davide256 said:

I like the Linear Tube Audio MZ2 I have, it performs amazingly well as a 1 watt class A amp with my Magnepan 1.7 speakers using the JS-2 for DC power supply. I'm thinking of pairing the MZ2 with their Zotl 10MkII amplifier as I think that would give me the added db's I need but would prefer to use

(trust) a JS-2 instead of their LPS for stablity under full PS load. Can a JS-2 be configured to support this?

"The ZOTL10 comes with a power supply that supplies 10A of 24V. "

 

Hi Dave:

A nice thought, however:

a) the JS-2 definitely can not be configured to produce 24V;

b) at 12V, 7.4 amps (with full 12VAC input) is the max we can continuously output;

c) the LTA ZOTL10 MkII already comes with a nice PS with Belleson regulators;

d) the supply it uses may in fact be a bi-polar (+ and -) DC supply, whereas the JS-2 is just +DC.

 

I always like to give a complete answer--and to learn about other products which use external DC supplies. So when my Googling did not turn up details on the LTA supply other than seeing that it uses a Neutrik SpeakON connector (which can be anywhere from 2-pole to 6-pole), I decided to give Linear Tube Audio a call.

I met David Berning (of ZOTL fame) decades ago, when he was offering his tube amp as the ultimate car stereo amp! And I was tickled to see how Mark Schneider has expanded the ZOTL offering to a whole range of models in just a few years. While Mark is not who answered the phone, I had a pleasant chat with a fellow there who already knew of UpTone and who owns a Sonore ultraRendu. He is going to get back to me with further details about the PS for the LTA ZOTL10 MkII (most specifically if it is a bi-polar supply). I'll pass along anything new or interesting. BTW, I mentioned to him that you are using their MZ2 to drive your Maggie 1.7s and the shock in his voice was priceless! 

 

Cheers,

--Alex C.

[ikemi]

Well I guess I’m an idiot then for buying a JS-2. Hey Alex, any chance I can return my JS-2 for a full refund!

 

[Superdad]

1 hour ago, davide256 said:

"The ZOTL10 comes with a power supply that supplies 10A of 24V. "

 

So I just received a very nice and informative reply from LTA, and it is very much worth sharing because it turns out the external PS box for their ZOTL10 is not a complete supply.  Here is the what was said:

 

Alex - 

Good to talk to you just now. 

As we discussed, there is no (easy) way to use an external power supply with the ZOTL10 Mk II. Most of the power supply is inside the amp, it's just the toroidal transformer that's in the external chassis.

It uses a full wave rectifier, so it's + and -, though - is treated as 0 volts. The umbilical we use is four conductor, but we only use three for the ZOTL 10 Mk II.

If you or the customer has any other questions, just let me know!

Stay healthy, stay safe!

Nicholas Tolson

Director, Sales & Marketing // Linear Tube Audio

301.448.1534

[davide256]

21 hours ago, Superdad said:

 

Hi Dave:

... I'll pass along anything new or interesting. BTW, I mentioned to him that you are using their MZ2 to drive your Maggie 1.7s and the shock in his voice was priceless! 

 

Cheers,

--Alex C.

When I had a 15x20 listening room it wouldn't have been possible. But with a smaller 12x12 listening room its working. The MZ2 is very sensitive to a straining power supply,

one of the first things I did with it was swap the stock SMPS to an HDPlex 100W as I could hear strain/edginess trying to drive Hifiman HE400 headphones. Since then I've

tried SoTM SPS500 and HDPLEX200W driving the MZ2,  better for headphones but neither gave me a reason to pull the 50W Prima Luna  Premium or

100W modified Hafler DH200 amps out of the speaker chain, the MZ2 just sounded feeble in comparison

Using the JS-2 on the other hand makes me wince when the Hafler is put back in, so much lost information and the bass definition is sucked out. The real kicker was that while

my Gumby was in for Unison upgrade this past week, I decided to put my Linn Genki CD player back into service. I had lost interest in it a number of years ago as not sounding

better than streaming. Not so now... the dynamic contrast from it is better than my streaming setup. Looks like I've become a convert to the first watt principle, that the JS-2

allows the MZ2 to function sublimely within its 1W power range.

[davide256]

@SuperdadRunning into a problem while playing around with a Chord Mojo, realized that it had been there also but at much fainter volumes with the Schiit Gungnir.

 

Configuration: JS-2 optioned at 2x12V DC connected to NUC8i7BEH as USB audio source and LTA Microzotl 2 as headphone/speaker amplifier

 

With either DAC USB connected to NUC  and RCA connected to MZ2 I get a background of random computer noise on all connected/unconnected RCA inputs, noise

volume level remains basically the same regardless of volume knob position. Putting the original MZ2 power supply into use for either component eliminates the problem.

 

What I suspect is happening is that noise from the NUC is somehow being transmitted through the JS-2 and that when NUC and MZ2 are connected in common  through a DAC a circuit and signal is being created in the power amplifier section of the MZ2.

 

Your thoughts, anyway I can fix this that doesn't involve buying a second JS-2? 😉

[Superdad]

3 hours ago, davide256 said:

Configuration: JS-2 optioned at 2x12V DC connected to NUC8i7BEH as USB audio source and LTA Microzotl 2 as headphone/speaker amplifier

With either DAC USB connected to NUC  and RCA connected to MZ2 I get a background of random computer noise on all connected/unconnected RCA inputs, noise

volume level remains basically the same regardless of volume knob position. Putting the original MZ2 power supply into use for either component eliminates the problem.

 

Hi David:

Thanks for your message.  You are forming a loop--from your JS-2, to the NUC, to your DAC, to your amp, and back to the JS-2.

 

The JS-2’s DC outputs are “floated” (though the chassis and shield of the transformer are grounded to AC mains for safety) and separately regulated.

Yet the two -VE/0-volt “grounds” of the JS-2’s separately regulated outputs are common to each other (because only one R-core transformer secondary, one set of Schottky diodes, one large filter choke). 

 

You could try connecting one of components back to AC mains ground to see if that eliminates the issue.

The JS-2 chassis screws are common to its AC inlet ground pin, and since it is the whole -VE/0-volt DC "ground" domain I am suggesting you try grounding, you could just as a test touch one end of a wire to a JS-2 chrome-plated top cover screw and the other end to the shell/barrel of any of the DC plugs. I'm not promising that will solve it, but if it does we can work with you towards a cleaner implementation of that.

 

Best,

--Alex C.

[davide256]

21 hours ago, Superdad said:

 

Hi David:

Thanks for your message.  You are forming a loop--from your JS-2, to the NUC, to your DAC, to your amp, and back to the JS-2.

 

The JS-2’s DC outputs are “floated” (though the chassis and shield of the transformer are grounded to AC mains for safety) and separately regulated.

Yet the two -VE/0-volt “grounds” of the JS-2’s separately regulated outputs are common to each other (because only one R-core transformer secondary, one set of Schottky diodes, one large filter choke). 

 

You could try connecting one of components back to AC mains ground to see if that eliminates the issue.

The JS-2 chassis screws are common to its AC inlet ground pin, and since it is the whole -VE/0-volt DC "ground" domain I am suggesting you try grounding, you could just as a test touch one end of a wire to a JS-2 chrome-plated top cover screw and the other end to the shell/barrel of any of the DC plugs. I'm not promising that will solve it, but if it does we can work with you towards a cleaner implementation of that.

 

Best,

--Alex C.

Thanks, will test and report back. Had turned all gear off last night, JS-2 connected to both components again, no symptoms right now, waiting for noise to come back.

[Superdad]

27 minutes ago, davide256 said:

Thanks, will test and report back. Had turned all gear off last night, JS-2 connected to both components again, no symptoms right now, waiting for noise to come back.

 

Well I would not think that would be something intermittent.  Is there a chance that you have also have some other connection in common? For example (and we have seen this before) say an HDMI video cable from your NUC to a TV, and also from that TV to your amp?  You can see how that too would form a side loop of ground domains.

[davide256]

No other wired connection to the NUC than EtherRegen, USB cable, and JS-2. Will check this evening when I return from work. I am suspicious

of the internal wifi card but haven't researched disconnecting that yet.

[davide256]

Gave connecting the top chrome screw to barrel ground plug/outer connector a try, no change. I've just ordered an Akasa Turing

case for the NUC, will see if eliminating fan and disabling wireless elimnates the noise

[jacquesr]

Hello Alex,

Would you know what cable I need to power a Sonicorbiter i7?

Thanks a lot. 

[MrDerrick]

I believe the STi7 end is a 7.4 x 5.0 mm inlet.

[Superdad]

2 hours ago, jacques_racine said:

Would you know what cable I need to power a Sonicorbiter i7?

 

1 hour ago, MrDerrick said:

I believe the STi7 end is a 7.4 x 5.0 mm inlet.

 

That is correct.  And here is an adapter that takes 5.5mm x 2.5mm at its rear and exits with a 7.4mm x 5.0mm plug:

https://www.bixpower.com/CNT-C24-p/cnt-c24.htm

[jacquesr]

Many thanks.

[davide256]

On 6/5/2020 at 12:31 PM, davide256 said:

Gave connecting the top chrome screw to barrel ground plug/outer connector a try, no change. I've just ordered an Akasa Turing

case for the NUC, will see if eliminating fan and disabling wireless elimnates the noise

@Superdad  have resolved the problem. Turing case no impact. Observing the phenomena over time, it appears to be driven by NUC I/O activity,

as its constant after reboot during library resynch. Wrapping a ferrite core on  both JS-2 DC leads has eliminated the issue.