[b0bb]

I'm definitely tempted to try a nice linear power supply for my SU-6 at some point, but I also don't want to spend a whole pile of money on something that may not even make a discernable difference. I think I would more so do it in an attempt to eliminate all single switch mode power supplies from being either on the same circuit as my gear, or even sitting close by.

The elephant in the room here is the high powered switched mode regulator (VRM) driving the CPU of the computer host supplying the audio data via usb.
The discussion below puts in some actual numbers

I use a NUC8i3, it consumes 7W while delivering audio to the DAC.
CPU operates at 1V, this means there is 7A of pulse current flowing into ground while running.

Assuming ground plane impedance of 1 milliohm (0.001 ohm), there will be 7mV at the ground connection closest to the CPU.

This 49dB below full scale output on a typically unbalanced RCA connection of 2V max output, effective SNR here is 49dB

The level of noise at the metal shell of the USB connector on the PC is the critical one here.

Intel certifies the NUC8 as compliant with FCC Class B (Title 47, Part 15 Clause B)
https://learnemc.com/emc-regulations-and-standards

The conducted interference allowed by the FCC varies across frequency with an average of 60dBμV
This translates to 1mV noise at the USB metal shell.

1mV ground borne noise to the DAC.
SNR is 66dB a far cry from the 130dB SNR the ES9038Pro converter on my DAC is capable of.

Once the connection between the metal shells of the USB and HDMI connector on the SU6 is broken, a big chunk of the lost SNR comes back.
(The PC and DAC will require the earth gound connection aka 3pin vs 2pin power to wall socket to make both sides are properly tied to ground to prevent uwanted EMC radiated inteference and potentially to meet local electrical code requirements)

The 9038 uses a DS modulator, in simple terms it counts and sums up energy pulses.
Spurious EMI adds unwanted energy pulses affecting performance.

Meeting the FCC ClassB noise requirements is a non-trivial task requiring careful construction of the motherboard and PC enclosure.
It buys up to 17dB improvement in ground borne noise in simple endpoint duties.

This is something the average DIY PC will not be able to achieve, this leaves a lot of potential performance on the table when it comes to DS DACs.

The numbers are from a simple endpoint.

On a full blown PC running HQPlayer and GPU offloading, CPU power consumption goes up to 110W, 110A peak current vs 7A, resulting in roughly 15x or 24dB more noise, around the CPU.
(What noise levels exist at the USB connector is an open question in this DIY case as EMC testing is quite specialized and expensive)

A proper FCC certified EMC testing setup starts north of 50K USD. The good ones are above the 500K range.

(The NUC8 has wifi and bluetooth, this meant Intel had to do extra work to keep motherboard noise down in the 0-60MHz baseband and 2.4xGHz transmission range, this has the flow on benefits at the 5-30MHz range where my DS DAC operates)

 

[Gilberto 62]

Good afternoon gentlemen. Forgive me for an apprentice inquiry, but this is where the source of knowledge and help is. I listen to my music from PC to LKS + Amanero usb upsampled to dsd512 with a satisfactory result for me, but reading to you, I see that you sometimes talk about Singxer devices. As I am always looking for an improvement, my question is if you think that inserting a Singxer SU6 between my pc and the dac would obtain a significant improvement or upgrade. Do you think I would have a better SQ ...? Or would it be wasting money ...? Thanks, as always, for any feedback from you. Greetings to all ....

 

[arjuna93]

Has anyone tried using it with Chord DACs?

 

[b0bb]

Mod to improve performance of the SU6 by replacing the 3 galvanic isolators

Sonic improvements
1) Reduces the grain in the preentations, sibilants greatly reduces
2) Removes edginess of the sound, snare drums on the SU6 no longer breakup into a mess.
3) Able to keep the various elements of the track (vocals, percussion, strings) separated when things get busy eg orchestra, pieces and EDM tracks with lots of overlaid tracks
4) Greatly improves bass depth and slam
5) Much smoother midrange

These are the 2x Texas Instruments ISO7641 data isolator for the data from the XMOS chip

This is the Silabs Si8620BB for the reference clock signal from the FPGA to the XMOS

The existing isolators have 2 specific issues that can be improved
1) High jitter about 300ps
2) Noisy, data is sent over a modulated data carrier. This adds additional RF noise to the clean side.

This creates a bottleneck that limits the performance of the SU6 interface.

The replacements:
1) 3x less jitter, pulse jitter about 100ps
2) Uses different isolation transport, Giant Magneto-Resistive (GMR) vs capacitive, data carrier not required. Much less noise to deal with.
3) Better dielectric isolation, 6kV vs 4kV for the data isolators

Device is the IL717V for the data and IL711-3 for the reference clock, both from NVE Electronics.

 

[b0bb]

Replacement of stock supercap with unit from Eaton
ESR improves from 40mOhm to 24mOhm

Eaton supercap

Stock Vinatech unit

 

[Gilberto 62]

Good Morning. About to buy the Singxer su6, please can someone tell me if powering my lks from the Singxer I2s output will be an improvement over the usb Amanero ....? Thank you....

 

[Muataz]

Good Morning. About to buy the Singxer su6, please can someone tell me if powering my lks from the Singxer I2s output will be an improvement over the usb Amanero ....? Thank you....

No body can tell you, but it will add an additional filter between from you and the PC so may help. If I'm in your position I may try their DAC Singxer SDA-6 which had USB galvanic isolation with new akm4499 chip to experience a new thing completely

 

[Gilberto 62]

Thank you for your answer, Muataz...

 

[andy663]

Has anyone tried both Singxer-SU6 and iFi iGalvanic 3.0? Currently running from Macbook pro > Lush^3 > D90 DAC, wondering if anyone has any suggestions on what would provide the best improvement on SQ. Thanks in advance.

 

[iFi audio]

Has anyone tried both Singxer-SU6 and iFi iGalvanic 3.0?

I'd gladly read how they compare as well

 

[Muataz]

Has anyone tried both Singxer-SU6 and iFi iGalvanic 3.0? Currently running from Macbook pro > Lush^3 > D90 DAC, wondering if anyone has any suggestions on what would provide the best improvement on SQ. Thanks in advance.

SU-6 is a hub of digital inputs but ifi G3.0 only Galvanic isolation

 

[iFi audio]

G3.0 only Galvanic isolation

Affirmative, that's what iGalvanic3.0 provides.

 

[L Plate]

Ok, thanks for the tip, I got it to work as you said I unplugged everything and only put the coax

Strange when I took out the box, i didn't connect anything, but were only trying coax first, and when I can't get it working, I plugged in i2s and it worked right away...

But I guess nothing beats power cycle

Thanks!!!

Hi, can I ask whether if you have any issue with SU 6 and D90 dac? I am using SU 6 and D90 MQA dac. I can hear a loud buzzing popping noise each time I click 'Play' icon. My music player is Foobar2K and I use the DSDTranscoder as Asio to play DSD files. This buzzing popping noise occurs only when I play FLAC files or when I have different file codecs in my playlist. Example if playlist 1 is DSD file and followed by playlist 2 Flac file. During the last track of DSD file just at the last second before switching over to Flac file, a loud buzzing popping noise is heard. If I play all DSD files it doesn't happen. When I play Flac file and even when I stop, forward, rewind, pause - the buzzing popping noise is heard. I asked someone in a different forum and he advised that buzzing popping noise is due to device/driver. He further added that this is nothing I can do about it as some users do experience this in their sound system and others don't. Are you experiencing this issue I am facing?

 

[kingoftown1]

Are you using the singxer drivers?

 

[L Plate]

Are you using the singxer drivers?

Hi, thanks for your reply. Yes, I am using the latest Singxer driver 4.86.0 from their website. When I first had the issue, I wrote to the company. I gave him a description of my issue. He said my I2S cable is not compatible and that I shouldn't be using "fibre-optic" cable with "built-in chip". Definitely the HDMI cable is not. Given the benefit of the doubt, I bought Wireworld Chroma 7 HDMI 0.5m cable and I am still getting this annoying buzzing popping sound with Flac files. Just want to be clear that buzzing popping sound is only heard at the start of the 1st track when I click "Play" icon (not throughout the music) and at the end of the last track before moving on to a different codec such as DSD or vice versa.
Edit: I just realised you asked me if I am using Singxer drivers on Foobar. No. I am using DSDTranscoder downloaded from https://sourceforge.net/projects/sacddecoder/files/dsd_transcoder/ and I chose Mode 2. I found that this is far flexible and I can upsample Flac files to DSD 512.

• Mode 2: Bitperfect outputting native DSD through DSDTranscoder