I have spent some time swapping components in/out of my USB signal path to see how the combination of a Singxer SU-1 and Intona USB isolator would change the performance of my Holo Spring DAC.
 
I have a Windoze 10 laptop and have found that "straight USB" output to the Holo Spring sounds "meh".  It's good, but not inspiring.  
 
I'll share an example of how the different combinations of equipment changed my perceptions of one song - Eric Clapton's performance of Signe from his unplugged album.  It's a small setting in front of a live audience.  You can really focus on the details in this simple performance.
 
Adding the Intona by itself made a significant difference in my system.  ...and I have been a skeptic of USB decrapifiers!  With the Intona I felt an improved the soundstage.  The crowd noise wasn't 2-dimensional, the audience seemed to wake up and I got a sense of a wider soundstage. 
 
Next I took the Intona out of the stage and plugged into SU-1 by itself.  The sound of the triangle ringing improved.  The guitars presence improved and I could hear more details in the strings and fingerwork.
 
If I could afford only one device - I would opt for the SU-1. While both devices were significant improvements over straight USB.  I felt like I got more improvements in detail and soundstage with the SU-1.  (For the curious, I used the I²S output)
 
However, combining the Intona and the SU-1 really made the most significant difference in my system.  Most notably was the sense of soundstage.  As the track starts, there's a bit of banter between Clapton and his band.  The combination of the SU-1 & Intona made that little dialog a lot more realistic.  I lack the more eloquent words of a skilled author.  I can only sum it up as "you feel like you are there".  The crowd noise opened up even more than the intona or SU-1 alone and I got an sense of more detail overall.  The cymbals shimmered, the double bass is rich and the fingerwork on the guitar seems to come through.  The combination of the two worked very well for me.  The increase in detail over "straight USB" is fairly stark.
 
If you have a better source than a laptop, the SU-1 might make less of a difference in your system.  YMMV.
I can say that the combination of the two is the right choice for me.
 
 

Hi for those interested in the matter,
 
Singxer must publish a firmware in a few month ("next month or next next" as they told me !). Support of DSD512 and probably other minor correction/improvements.
 
Also a new Singxer model of DDC must hit the market in August (shenzhenaudio answer on a SU1 question) and when i ask about it to Singxer directly they told me : "i think the new DDC will be better than SU1.".

Any specific offered about what the improvement planned for the new Singxer DDC are, and expected pricing? I'm interested in the SU-1 but don't want to pull the trigger if a better implementation is around the corner.
 
Thanks!

Not on my side sorry... they just told me what i wrote. You could try to reach them at leter@singxer.com but i think it's perhaps too early to have such kind of information. Let us know !

IMO - the current SU-1 benefits greatly from an upgraded power supply. The original version in my system was pretty bright (my speakers are probably peaky in the highs), but I changed the output-half board PS to an Uptone Audio LPS-1 (also worked well with a hand-made supercaps hybrid PS).  The input-half is 220V regenerator->nice LPS->iFi DC iPower->W4S Recovery->SU-1.
 
This SU-1 now soundly beats my Tanly DDC in areas of overall detail, top end clarity, and bass tightness.
 
So I hope any future DDC will improve the on-board PS or allow input from an optional external source.

Mine is not that bright on my system but yeah some sort of glare sometimes (meaning the high can sound better).

I don't know perhaps it can be software related too... The only user that i've read about firmware update for his Singxer F1 have reported that it was a bit smoother after it.

http://www.head-fi.org/t/825912/singxer-f-1-firmware-update

motberg said:

  IMO - the current SU-1 benefits greatly from an upgraded power supply. The original version in my system was pretty bright (my speakers are probably peaky in the highs), but I changed the output-half board PS to an Uptone Audio LPS-1 (also worked well with a hand-made supercaps hybrid PS).  The input-half is 220V regenerator->nice LPS->iFi DC iPower->W4S Recovery->SU-1.
 
This SU-1 now soundly beats my Tanly DDC in areas of overall detail, top end clarity, and bass tightness.
 
So I hope any future DDC will improve the on-board PS or allow input from an optional external source.

Click to expand...

Could you post some pictures of upgraded PS and eleborate on this?

motberg said:

  IMO - the current SU-1 benefits greatly from an upgraded power supply. The original version in my system was pretty bright (my speakers are probably peaky in the highs), but I changed the output-half board PS to an Uptone Audio LPS-1 (also worked well with a hand-made supercaps hybrid PS).  The input-half is 220V regenerator->nice LPS->iFi DC iPower->W4S Recovery->SU-1.
 
This SU-1 now soundly beats my Tanly DDC in areas of overall detail, top end clarity, and bass tightness.
 
So I hope any future DDC will improve the on-board PS or allow input from an optional external source.

Click to expand...

 

roger7 said:

  Could you post some pictures of upgraded PS and eleborate on this?

Click to expand...

 
Also interested in this.

This is nice...and more expensive!
 
https://kitsunehifi.com/kte-kitsune-tuned-edition-singxer-su-1-tuned-psu-amongst-other-options-as-a-package-deal/

jozurr said:

   
 
Also interested in this.

Click to expand...

Hi Guys,
I did not do the SU-1 PS mod personally, it was done by a friend who has some experience in this as a hobby,
I believe he changed the transformer, somehow charged 3x ultracaps and then regulated with LT3042.. but not sure.
I do not know much about this, but will ask him if he thinks he is ready to post his recipe for this PS. I believe it is very cheap, iirc the parts were less than 40 USD.
He has a few work-in-progress outboard versions of this PS that we quickly compared directly against my LPS-1 driving a DDC.
His PS was a little less dynamic, softer but without any bass mushy-ness, I believe he has since modified the design to improve the dynamics. 
He also installed a 5.5/2.1 DC jack that I can optionally use - just need change the plug on the SU-1 board from the on-board PS to the DC Jack mounted on the back plate.
I have compared my LPS-1 to the on-board ultracap PS and the effect was same as mentioned above, the LPS-1 is same quiet but the LPS-1 has more dynamics.
The nice thing about the DIY ultracaps PS, was there was no bass mush that I have encountered from using batteries in the past (from Kingrex and some others).
 
The original SU-1 PS was relatively harsh in my setup with 2 different DAC's, which I am sure was due to my speakers probably having a minimum 4db peak around 10k and overall maybe not very linear in the highs.
 
My guess is the easiest way to improve the SU-1 would be to run a DC jack to the back panel for the SU-1 output section and feed it with a higher quality LPS (such as the Teradak DC-30 range or better) and maybe filter with a iFi DC iPurifier in line right before the DC jack input. I have found this combination in other uses very good and similar setups are now driving my PPA v2 USB card and the Recovery re-clocker.
 
I am traveling now and will not be back for a few weeks, but will try this option ASAP and compare to the LPS-1 also - so I have some options on how to better disperse my various PS investments.
 
I must say that the SU-1 now offers more detail than my beloved Tanly (the Tanly is up next for PS mod..). With the SU-1, cymbals are more realistic, bass is tighter, mid-range and vocals more natural.

winders said:

  This is nice...and more expensive!
 
https://kitsunehifi.com/kte-kitsune-tuned-edition-singxer-su-1-tuned-psu-amongst-other-options-as-a-package-deal/

Click to expand...

 
Interesting find, could be a nice upgrade !!
 
Will be pleased to have a word of "bimmer100" here on what are the evolution performed (before/after measurments). Are the modification are only the fuse, the caps and the better cable going from PS to main board ? Is the PS still the same (i'm mean do they only put a sticker on it...), better regulators etc... ?
 
Finally is this an easy upgrade meaning the whole PS board is swapped with the old one (plug and play) ?
 
Thanks a lot for any information

enigmus12 said:

   
Interesting find, could be a nice upgrade !!
 
Will be pleased to have a word of "bimmer100" here on what are the evolution performed (before/after measurments). Are the modification are only the fuse, the caps and the better cable going from PS to main board ? Is the PS still the same (i'm mean do they only put a sticker on it...), better regulators etc... ?
 
Finally is this an easy upgrade meaning the whole PS board is swapped with the old one (plug and play) ?
 
Thanks a lot for any information

Click to expand...

I think the best option is to use an external LPS of some kind to power the SU-1. I have an SU-1 coming from Singxer that has no internal power supply and has a 5 vdc receptacle on the back. This should be cheaper in the long run. 

enigmus12 said:

Interesting find, could be a nice upgrade !!

Will be pleased to have a word of "bimmer100" here on what are the evolution performed (before/after measurments). Are the modification are only the fuse, the caps and the better cable going from PS to main board ? Is the PS still the same (i'm mean do they only put a sticker on it...), better regulators etc... ?

Finally is this an easy upgrade meaning the whole PS board is swapped with the old one (plug and play) ?

Thanks a lot for any information

Click to expand...

As an MOT I can't really comment too much on this forum.

The KTE-SU1 has many improvements and the sticker on the transformer is NOT one of them obviously. Sorry to disappoint some of those who may think it contains quantum particles or some nonsense.

Our mods are simple and effective to being real world results that you can hear he improvements. Mainly dynamics and cleaner and dark black background and much improved transient response.

The stock Su1 has about 150uV of output noise, approx 70db PSRR (power supply rejection ratio and about 32mV line regulation.

Our KTE SU1 is at approx 3uV output noise, and approx 125db PSRR and about 1.8mV line regulation. It's purely discrete and this design is one of the best all in one solutions without any extra Clutter with external psu , boxes and extra cables. We also replace all the caps with FG nichicon caps of larger values and lower esr. Also the film caps are replaced with wima. The regulator is specially mounted with proper silicon grommet and silicon sheet to the heat sink and heat sink grounds are clipped. The hookup wire is a much higher grade hookup wire @ 1.3ohms per 1000ft, 70um silver plated copper, air dielectric, 1mm solid core twisted pair.

I would say the KTE-Su1 is easily comparable to any of the best upgraded/modded SU1's available. Albeit this is a very limited run of KTE-SU1's. I do the mods myself and must draw the line in how much time I can commit for this project. I truly am passionate about audio and do this for this main reason.

Further plans are to build dummy plates with D.C. 2.5/5.5 D.C. Inlets and work with Alex to sell the lps1 and su1 as a kit. It should be a good comparable option as I decide to complete my run of KTE-su1's. they all are individually serialized with tamper resistant warranty labels. Each unit get a minimum 72hour burn in and QC test process. This product will be limited to about 20 finished new units (complete and ready to ship) and about 20 upgraded units (you send in your Su1 you purchased from us previously, and you pay for shipping to and from and cost for upgrades)

Hopefully this answers most people's questions.

The overall lead time is roughly 2weeks or so. Depending on my schedule. We have orders turned off on our website and are only Manual orders via email to control the flow. Otherwise I would not be able to accurately quote turn around times. We already are about half sold out since announcing them a week or two ago. But I'm considering doing a larger limited or production depending on demand, but in no way will I do more than 40 complete units. My wife would kill me for spending more time with my soldering station than her

Thanks for all the usefull information about this kitsune upgrade I will not be in because my Singxer is from shenzenaudio and anyway I'll have prefered a Diy kit. Anyhow seems good in the paper and open some thought on the upgrade of the PS.

About the option of Singxer to provide a Su1 without PS, it's new to me and a lot of people were complaining of this option not being available when it goes out ! Cool to hear !

enigmus12 said:

Thanks for all the usefull information about this kitsune upgrade I will not be in because my Singxer is from shenzenaudio and anyway I'll have prefered a Diy kit. Anyhow seems good in the paper and open some thought on the upgrade of the PS.

About the option of Singxer to provide a Su1 without PS, it's new to me and a lot of people were complaining of this option not being available when it goes out ! Cool to hear !

Click to expand...

Singxer parts are available in request for warranty repair through a dealer. But if the couple hundred su1's I've sold... not one has had a failure with the psu or main pcb. So paranoia of a failure is nothing to worry about. He components we use in our KTE-Su1 are designed to last as well. It's built like a tank. And long after the KTE Su1 is no longer being made, it still will be around to do work on them if needed.
I will do work on other su1's from authorized resellers. So sorry for that confusion. The shipping to and from is the customers responsibility. Also note the factory singxer warranty is technically void after these mods. But for those who do these types of mods will rarely care less. I do do my own QA and burn in to be sure the quality is up to standard before sending back to the customer. I stand behind my own work, so will back it for repairs for a year after purchase yet shipping expenses will only be covered within the first 30days. Otherwise customer will pay shipping to me, and I will cover return shipping after the initial 30day guarantee. It's more than fair and I suspect not one customer will ever need to act on a warranty claim