[FredA]

Truly amazing how much misinformation has appeared in this thread - mostly regarding DSD along with some really bad guessing about how the R2R7 processes DSD.

The misinformation in the above post regarding DXD however is unprecedented with the correct information on DXD specifications but a few keystrokes away.
"DXD is a PCM signal with 24-bit resolution (8 bits more than the 16 bits used for Red Book CD) sampled at 352.8 kHz."
That's it - the truth.

The truth will set us free. Set us free please.

 

[gk2013]

Truly amazing how much misinformation has appeared in this thread - mostly regarding DSD along with some really bad guessing about how the R2R7 processes DSD.

The misinformation in the above post regarding DXD however is unprecedented with the correct information on DXD specifications but a few keystrokes away.
"DXD is a PCM signal with 24-bit resolution (8 bits more than the 16 bits used for Red Book CD) sampled at 352.8 kHz."
That's it - the truth.

Thanks, just to be sure I repeat: "DXD is a PCM signal with 24-bit resolution (8 bits more than the 16 bits used for Red Book CD) sampled at 352.8 kHz."

 

[Chopin75]

I really doubt for these DACs, the R2R will convert all DSD to PCM (though Sony did it for their flagship SACD players !). DSD is very much a 1 bit + filter., not needing and not possible to go through R2R, and there are numerous DACs now that have R2R + able to DSD with a separate circuit e.g:

Lampizator
Total DAC
Holospring


All can do DSD without going through R2R, as far as I know, though one may argue it can go to the 1 bit of the first ladder of R2R and that is it but I am not sure if it even pass through the first ladder at all.
Lampizator makes DAC with only DSD by taking out the R2R circuit.
The Chinese DACs' site have limited English ability so it is hard to understand clearly what they are talking about.

PS audio Direct stream digital has a similar direct pathway for DSD and it does not even do PCM
These direct methods should all sound better than Sigma delta though I have never owned or heard any of these pure DSD DACs.

 

[gk2013]

Yep, there is no DSD to PCM conversion done by the R2R7.

 

[christianvogel]

Thanks, just to be sure I repeat: "DXD is a PCM signal with 24-bit resolution (8 bits more than the 16 bits used for Red Book CD) sampled at 352.8 kHz."

I stand corrected. An honest mistake and taken with humble pie, I confused DxD with Wide DSD, which is 8 bit at 2.8224 MHz. Indeed DxD is 352KHz/24bit.

 

[doak]

I stand corrected. An honest mistake and taken with humble pie, I confused DxD with Wide DSD, which is 8 bit at 2.8224 MHz. Indeed DxD is 352KHz/24bit.

BKA: "DSD-wide"

 

[Chopin75]

Hey, a bit of topic but relevant:

The beloved US president may be putting a Tariff on Chinese products
https://www.cnn.com/2018/03/22/politics/donald-trump-china-tariffs-trade-war/index.html

Would it affect the price of Audio-gd and other Chinese audio products ? The article stated that it only will minimally affect consumers.
I am wondering if I should get the R2R 7 rather sooner than later ??

 

[DACLadder]

For Singxer SU-1 users the external +5V power supply mod is well worth the expense and effort. Less grain in the vocals is the main benefit I hear while using the M7S DAC. Slightly more open sounding with a touch more highs versus the original Amanero USB input. Of course you will also need a quality +5V supply. Channel Island Audio VDC-5 mk. II in my case.
Used this cable assembly/ adapter plate which made the mod task easy and affordable.... https://www.ghentaudio.com/part/dc99.html

Also, for those interested, while working on the SU-1 noticed the design provides galvanic isolation between the XMOS USB digital output to the FPGA/ output circuitry. The XMOS USB chip is powered exclusively from USB +5V source. The SU-1 internal (or external) power supply only provides power for the FPGA, clock oscillators, and output line drivers.

I would still like to compare a production M7S to the R2R 7. Has anyone done so? .... Bueller?

 

[Wynnytsky]

working on the SU-1 noticed the design provides galvanic isolation

so the intona should have much less to contribute when used with the SU-1 right?

That Ghent plate is going to destroy Kitsune's offering.

 

[seaice]

For Singxer SU-1 users the external +5V power supply mod is well worth the expense and effort. Less grain in the vocals is the main benefit I hear while using the M7S DAC. Slightly more open sounding with a touch more highs versus the original Amanero USB input. Of course you will also need a quality +5V supply. Channel Island Audio VDC-5 mk. II in my case.
Used this cable assembly/ adapter plate which made the mod task easy and affordable.... https://www.ghentaudio.com/part/dc99.html

Also, for those interested, while working on the SU-1 noticed the design provides galvanic isolation between the XMOS USB digital output to the FPGA/ output circuitry. The XMOS USB chip is powered exclusively from USB +5V source. The SU-1 internal (or external) power supply only provides power for the FPGA, clock oscillators, and output line drivers.

I would still like to compare a production M7S to the R2R 7. Has anyone done so? .... Bueller?

I agree with the SU-1 power mod. I had the original SU1 and then bought the Magna Hifi edition and the SQ improvements are really wortht it.

I have also found that cables and filtering may be important for SU-1. The following SU-1-related upgrades moved my HE7S to a new level:

My original setup:
PC>Supra USB 2.0 cable (1 meter)>Intona Industrial>Supra USB 2.0 cable (1m)>Magna SU-1>Audioquest Carbon HDMI (1 meter) or shorter HDMI cables>HE7S

Upgrade one (substantial SQ improvement):
PC>Supra USB 2.2 cable (1 meter)>Intona Industrial>Supra USB 2.0 cable (1m)>Magna SU-1>Audioquest Mocha (i.e. Coffee) HDMI (1 meter)>HE7S

Upgrade two (substantial SQ improvement):
PC>Audioquest Coffee USB cable (0.75m)>Intona Industrial>Supra USB 2.0 cable (1m)>Magna SU-1>Audioquest Mocha (i.e. Coffee) HDMI>HE7S

Upgrade three (subtle SQ improvement):
PC>Audioquest Coffee USB cable (0.75m)>Intona Industrial>ADL Fururech Formula 2 (1.8m)>Magna SU-1>Audioquest Mocha (i.e. Coffee) HDMI>HE7S

Every of these upgrade steps has brought only positives to my setups (HE7S>KGSSHV Carbon>Stax 009): More natural sound, more details but less hashness and less digital artefacts... More pleasure and music.

I will be testing Chord Dave at home soon and I am really curious if my HE7S will survive against Dave

 

[DACLadder]

so the intona should have much less to contribute when used with the SU-1 right?
That Ghent plate is going to destroy Kitsune's offering.

The Intona isolates the USB signal side where the SU-1 is after the XMOS USB receiver chip. I think it would depend upon the system/ setup and tolerance for interference. In my case I isolate USB power and feed linear +5V down the USB cable bypassing the computer power source. Not sure if it would make much of a difference. The Schiit USB Decrapifier did not do much after installing the JCAT USB driver board.

Kitsune tuned SU-1 replaces the internal power supply plus also swaps out low-voltage regulator(s) for better spec devices. I like getting AC and diode switching completely out of the box innards and just supplying it clean, steady state DC power. Will look into changing the SU-1 regulator at some point but the existing SU-1 regulator won't have to work as hard with cleaner input voltage. A better voltage regulator may have higher PSRR (power supply rejection ratio) but with cleaner power input there is lesser need to reject.

If I were to re-design the SU-1 I would put in separate voltage regulators for each of the two oscillators, FPGA, and I/Os. No sharing common power source. And for HDMI I2S I would also re-clock the FPGA output signals externally before sending to the HDMI cable driver chip. This would help avoid jitter buildup induced by the internal FPGA signal paths.

 

[FredA]

The Intona isolates the USB signal side where the SU-1 is after the XMOS USB receiver chip. I think it would depend upon the system/ setup and tolerance for interference. In my case I isolate USB power and feed linear +5V down the USB cable bypassing the computer power source. Not sure if it would make much of a difference. The Schiit USB Decrapifier did not do much after installing the JCAT USB driver board.

Kitsune tuned SU-1 replaces the internal power supply plus also swaps out low-voltage regulator(s) for better spec devices. I like getting AC and diode switching completely out of the box innards and just supplying it clean, steady state DC power. Will look into changing the SU-1 regulator at some point but the existing SU-1 regulator won't have to work as hard with cleaner input voltage. A better voltage regulator may have higher PSRR (power supply rejection ratio) but with cleaner power input there is lesser need to reject.

If I were to re-design the SU-1 I would put in separate voltage regulators for each of the two oscillators, FPGA, and I/Os. No sharing common power source. And for HDMI I2S I would also re-clock the FPGA output signals externally before sending to the HDMI cable driver chip. This would help avoid jitter buildup induced by the internal FPGA signal paths.

I am thinking of adding a linear supply to me setup to drive the Singxer f-1. One by Zerozone or Teradak.

 

[seaice]

I am thinking of adding a linear supply to me setup to drive the Singxer f-1. One by Zerozone or Teradak.

This would be very interesting. I believe that it may be really beneficial.

I would like to see the following comparison:
MagnaHifi SU-1 versus Kitsune SU-1 versus linear-powered SU-1.

I have upgraded from the standard SU-1 to the Magna Hifi version and the upgrade has been really helpful to the SQ of all of my Audio-GD DACs.

 

[DACLadder]

The Kitsune Tuned SU-1 appears to upgrade the shipped power supply with better electrolytic caps and different +5V output regulator. I originally thought the power supply was changed out but was fooled by a new transformer label. MagnaHifi does about the same but they do a better job of highlighting work performed. And they both swap out the +3.3V regulator and a few caps on the digital board. The parts used for upgrade by each company are most likely sourced from different vendors. But better speced parts certainly can provide greater performance overall.

 

[bballas]

sclk ex clocked singxer, powered sps500(+lt3045), or uptone Lps1.2 the most significant upgrade in my system.