UpTone JS-2 Power Supply Listening Impressions

[thyname]

Are the two output rails independent? In other words, is the galvanic isolation preserved when using both outputs for two separate devices in JS-2? Thanks 

[Superdad]

On 7/6/2019 at 6:53 AM, thyname said:

Are the two output rails independent? In other words, is the galvanic isolation preserved when using both outputs for two separate devices in JS-2? Thanks 

 

The JS-2 design has one R-core trans with a single high-current secondary, a single set of Schottky diodes, and a single large DC inductor/choke--feeding 66,000uF of capacitance--which in turn feeds two separate specially balanced cap>regulator>cap networks.

 

Both of the outputs are "floated"--that is their -VE output "ground" is not common to AC mains ground (as is often the case with other supplies), but indeed they are common to each other and therefore the JS-2 outputs are not galvanically isolated.

 

I hope this information is helpful to you. 

 

By the way, I have seen a few other multi-rail linear power supplies which, while having more than one transformer secondary and more than one diode bridge, still had its outputs with -VE ("ground") common to each other--and to AC mains ground (yuck on the latter).  I think the earlier HDPLEX units were this way and I think Keces still is.

[R1200CL]

18 minutes ago, Superdad said:

therefore the JS-2 outputs are not galvanically isolated.

But will that affect anything?

 

Like if you’re using dual LPS-1.2 and a SonicTransporter ?

 

Or just an opticalRendu and a EtherRegen ?

[jamesg11]

Yes, knew this re js-2 & isolation, & hence was aware of potential sonic compromise when I powered the mac mini + ultrarendu from it.

I’ll get round to using lps1.2 on the rendu ... but - for my edification! - what is the extent of the downside running both mini & rendu off the js-2?

[Superdad]

1 hour ago, R1200CL said:

But will that affect anything?

Like if you’re using dual LPS-1.2 and a SonicTransporter ?

Or just an opticalRendu and a EtherRegen ?

 

Well you are not really clear in your above examples.  

a) How would separate UltraCap LPS-1.2 units be related to a JS-2 powering a SonicTransporter?  [1: The -VE of the charging side of an LPS-1.2 is always completely isolated from the output of the UltraCap unit; 2: A JS-2 powering a SonicTransporter is not going to have enough current left over to charge two LPS-1.2s--not that there would even be any benefit to doing so.]

 

b) While some loss of galvanic isolation might occur for an opticalRendu and EtherREGEN with common -VE supply, the EtherREGEN is already highly (actively) isolated, so I doubt any degradation would be heard.

 

 

1 hour ago, jamesg11 said:

Yes, knew this re js-2 & isolation, & hence was aware of potential sonic compromise when I powered the mac mini + ultrarendu from it.

I’ll get round to using lps1.2 on the rendu ... but - for my edification! - what is the extent of the downside running both mini & rendu off the js-2?

 

We have people do this all the time.  Works and sounds great.

I'll put it this way: There is more upside to be gained from powering an ultraRendu from the ultra-low output impedance / ultra-low noise LPS-1.2 than there is downside of the ultraRendu being powered by the JS-2 due to it having common -VE with the Mac mini.  Hope that makes sense.

[jamesg11]

You are definitely getting more subtle in your articulation of ‘problem’ situations, as the years pass the door. But, I get it.

[R1200CL]

6 hours ago, Superdad said:

Well you are not really clear in your above examples.  

My post no 415, previous page may be more clear, but I guess you answer some of it now. 

[musicguy]

First , A big thank you to Mr Crespi. His upgrades to my mac mini and suggestions  have been magical.  The improvements in sound have been huge!!

 

2014 Mac mini -mmk-js-2-isogen-lps 1.2 =  huge upgrade in sound!!

 

musicguy

[rncasper]

I'm thinking about purchasing a JS-2 to power both a BROOKLYN DAC+ and a SonicTransporter i5--any thoughts/issues? Thanks.

[Superdad]

15 hours ago, rncasper said:

I'm thinking about purchasing a JS-2 to power both a BROOKLYN DAC+ and a SonicTransporter i5--any thoughts/issues? Thanks.

 

Piece of cake for the JS-2 to power both simultaneously.  

 

Thanks also for your call---and for your JS-2 order! 

[rncasper]

My pleasure, and MUCH thanks for the in-depth conversation. Very useful--and can't wait to get my JS-2/see what everyone's saying . . . 

[nbpf]

I have just realized that it is about one year since I have bought a JS-2 and I feel it's time to say again thanks to the UpTone Audio team for making available such a great product! During the last year, I have used the JS-2 mainly to power an LPS-1.2 and an Allo DigiOne Signature and it has worked flawlessly. Meanwhile, the JS-2 has become an integral part of our living room. It has taken hold of a shelf below the Naim DAC and the SuperNait 2 and I enjoy its design and build quality every day.

[JSWBach]

I am a Japanese audiophile. I got JS-2 a week ago. Before describe my impression, let me explain about the digital part of my audio system before introducing JS-2. 
Basic construction is:

Mac mini --> MUTEC MC3+USB --> MYTEK Brookln DAC+

MC3-USB and Brookon DAC+ are synchronized by the clock from a clock generator. Further I am using 10MHz OCXO clock for the clock generator.
Between Mac mini and MC3+USB, I used a USB isolator (HUMANDATA USB-029H2-RP). 
I used a DC power supply for Brookon DAC+, but the result is not so good. So I was looking for a good power supply.

The reason that I know UpTone Audio is USPCB A>B Adapter which some Japanese audiophile uses. I was very surprised by the sound when I used this adapter in place of a USB cable.
Then I visited the UpTone Audio homepage, and I found JS-2 and MMK, and I visited this forum. I decided to buy JS-2 and MMK.

The result is much better than I expected. The sound becomes very much clearer. Now I enjoy the sound by JS-2 and MMK. I appreciate Alex Crespi and the members of this forum.

[Superdad]

5 hours ago, JSWBach said:

I am a Japanese audiophile. I got JS-2 a week ago. ....

....The result is much better than I expected. The sound becomes very much clearer. Now I enjoy the sound by JS-2 and MMK. I appreciate Alex Crespi and the members of this forum.

 

Thank you so very much for joining Audiophile Style just to share your kind words.  We hope that you enjoy your JS-2 powering your Mac mini and Brooklyn DAC+ for many years. And even if your system changes in the future you will find use for the JS-2 with other audio components.

 

We do not have as many JS-2s in Japan (maybe about 15 that I know of) as we do in other countries but we hope that word will spread there. 

And always feel free to ask questions here in this forum or via direct e-mail contact.

[Krishnan]

Alex, thank you for all the answers to my inquiries, and the prompt shipment of the JS-2. I am from India, yet the Uptone team made the purchase completely hassle free.

I bought the JS-2 to power the SOTM SMS200 and clock. While waiting for the devices, I thought I would try powering my passive pre-amp. (My setup : Musical Fidelity M1CDT+DAC->Tortuga Audio Balanced Passive pre->Schitt Vidar mono blocks->Monitor Audio PL100s).

I wish all audio equipments have an external DC option that can be powered by a JS-2. Being new to Linear Power Supply, I was simply blown away to notice how much improvement a good LPS can add to your setup.

Though a Passive pre-amp has very minimum circuit path that depend on DC power, JS-2 brought in a significant improvement to the output. Specifically, I could notice a more prominent darker background. The over tonality got refined leading to improved sound stage and imaging. Overall songs sound more "musical" and very refined.

 

Great product from up-tone!

[Barton]

Has anyone with a sensitive system compared JS-2 vs lps-1.2 for powering just an ultrarendu or optical rendu? Thanks in advance.

[kennyb123]

2 hours ago, Barton said:

Has anyone with a sensitive system compared JS-2 vs lps-1.2 for powering just an ultrarendu or optical rendu? Thanks in advance.

 

I preferred the LPS-1.2 over the JS-2 for powering my microRendu 1.4 - but in my situation I was using the other rail in my JS-2 to power a Mac mini.  I even preferred an LPS-1 over that second rail as I reported here:

 

 

[lxgreen]

What is the difference between the JS-2 and the power supply in the Signature RenduSE?

[Superdad]

14 hours ago, lxgreen said:

What is the difference between the JS-2 and the power supply in the Signature RenduSE?

 

The JS-2 is a dual-output, choke-filtered, 5~7.6 amp linear power supply with custom R-core transformer—and was designed by John Swenson.

 

The power supply in the Signature RenduSE is a single-rail, low-current supply built into the chassis and dedicated to producing about 7V for the ultra/optical Rendu. It was designed by Sonore associate Barrows Worm and utilizes a custom toroidal transformer and I believe Belleson voltage regulator modules.

[jcn3]

My second JS-2 has arrived!  I could tell an immediate improvement in detail, texture, and soundstage (primarily depth).  Look forward to it actually warming up.

 

[Rhed6]

Can the JS-2 power the Enther REGEN and ISO REGEN? If so, any benefits if any going this route? I do have the ISO with the UC 1.2. 

[andru26]

1 hour ago, Rhed6 said:

Can the JS-2 power the Enther REGEN and ISO REGEN? If so, any benefits if any going this route? I do have the ISO with the UC 1.2. 

From Uptone website:

 

JS-2 has can generate up to 7A of current and each output can be used at 5V, 7V, 9V, or 12V.
The EtherRegen has an input range of 7V/1.4A, 9V/1.0A, 12V/0.8A

Uptone Audio recommends powering the ISO Regen with the UltraCap LPS-1.2, which has an output of 1.1A.

From the above info, it's very clear that JS-2 can easliy power the two devices with its max 7A output.
The question you might want to ask is whether using two separate UltraCap LPS-1.2 for powering the devices might yield better results due to the galvanic isolation of the LPS-1.2.

[jamesg11]

... currently, I’m using the JS-2 to power the lps1.2 ...! As well as RME dac.

(& yes, I like a pun).

[seaharp1]

On 2/19/2020 at 12:00 PM, jamesg11 said:

As well as RME dac

Hi,

 

What is the barrel size for the RME ADI-2?

 

Thanks

[Superdad]

7 hours ago, seaharp1 said:

What is the barrel size for the RME ADI-2?

 

My records, based on e-mails with JS-2/RME ADI-2 owners, indicated that the DC input jack for that DAC is 5.5mm x 2.1mm.