[DACLadder]

The R8 MK2 does not employ switching power. The digital board has two large linear regulators feeding DC to nine chip type linear regulators for the circuits. Analog circuits have 4 Class A regulators. Class A is just another term for linear, always conducting power.

You could argue the HE supplies are a type of DC-DC switcher but only at 50Hz and a sine wave at that. Not at all like a cheap switcher that generates 100Khz+ and feeds a square wave to a small inductor.

Kingwa’s DACs with V2 DAC boards take a long time to break in. The R27 has been shipping for a month so would not trust a review until June 2022.

 

[DACLadder]

The only Opamps Kingwa uses are for DC offset control (servo) in the analog stages. They are not in the direct signal path. Kingwa said the Opamps have better precision versus building the circuits out of discreet parts.

 

[Presence]

Pops on track changes with R8 with 10M clock input FW

I found it strange that I have been getting about a 50% rate of static pops when changing tracks both intra and inter album, library to library and streaming....
Roon has been putting out frequent patches lately, one of which I just implemented pertaining to Roon bridge. [Version 1.8 build 943]
The pops have 99% gone away. The 1% are very soft and unobtrusive.

 

[gimmeheadroom]

Kingwa’s DACs with V2 DAC boards take a long time to break in. The R27 has been shipping for a month so would not trust a review until June 2022.

You mean the R-27HE? I thought the R-27 (non HE) has been around for a while.

 

[DACLadder]

Any DAC with the V2 DAC boards I would think. My R7 HE MK2 took every bit of 750-1000 hrs. to sound great. HE7 MK2 was just a few weeks.

 

[gimmeheadroom]

No, my question was because you said the R27 has been shipping for a month. I guess you mean the new model R-27HE which is not the same at all as the R-27 2021?

 

[DACLadder]

Sorry for the confusion. Any new DAC with the V2 DAC boards.... R7, R8 , R27 with and without the HE supplies.

 

[Thorbee]

For those interested the AGD R-27 2021 (latest updates) in my opinion is very close to the AGD R-27HE with the main difference being blacker background, slightly more dynamic and a “cleaner” overall presentation favoring the HE. These differences are NOT huge but definitely noticeable. I also like the fact that Kingwa will give you different remote codes to control multiples in the same room as well. I would say that if you were looking at either the HE would be worth the extra if you want to take advantage of the user interfaces improvements. Now what is funny is even with the various power conditioning that I am using the differences are subtle so maybe without delta may be larger but not sure. Anyhow hope this helps in some way for those trying to decide between the two.

 

[tonedeafmelomaniac]

According to Audio-gd website r2r-11 mk2 is the only "Real NOS discrete R-2R DAC design" in the current product lineup, correct me if I'm mistaken. I was wondering how NOS mode is implemented in other Audio-gd dacs, whether it's true NOS without FPGA engaging or sort of approximation?

And what's the difference between OS-0 and NOS modes in R-1 2021 version dac?
"While OS setting on "O" mean the DAC working under oversampling mode, lower number OS modes sound became warmer and smoother. Or depend on your sense .
Mode "0" : class technology NOS mode.
Mode "2" : 2X oversampling.
Mode "4" : 4X oversampling .
Mode "8" : 8X oversampling.

While OS setting on "N" mean the DAC working under NOS mode, it has one mode now, it is the full new NOS configure design."

 

[FredA]

According to Audio-gd website r2r-11 mk2 is the only "Real NOS discrete R-2R DAC design" in the current product lineup, correct me if I'm mistaken. I was wondering how NOS mode is implemented in other Audio-gd dacs, whether it's true NOS without FPGA engaging or sort of approximation?

And what's the difference between OS-0 and NOS modes in R-1 2021 version dac?
"While OS setting on "O" mean the DAC working under oversampling mode, lower number OS modes sound became warmer and smoother. Or depend on your sense .
Mode "0" : class technology NOS mode.
Mode "2" : 2X oversampling.
Mode "4" : 4X oversampling .
Mode "8" : 8X oversampling.

While OS setting on "N" mean the DAC working under NOS mode, it has one mode now, it is the full new NOS configure design."

I think with os0, no processing at all is done. With NOS, some digital filtering is done on the samples. NOS sounds better.

The r2r 11 mkii does no digital processing. It uses only anlog filtering.

 

[gimmeheadroom]

I think with os0, no processing at all is done. With NOS, some digital filtering is done on the samples. NOS sounds better.

The r2r 11 mkii does no digital processing. It uses only anlog filtering.

Thank you, Fred! Kingwa had told me NOS and OS0 are not the same, but I don't think he gave any details. I wonder if anybody in this thread who speaks Chinese could contact Kingwa and get us some details on this. I would be interested to know more.

On another topic related to the DI-20HE, can anybody recommend a heat shield wrap for cables that does not pose any health risks (i.e. no fiberglass etc.) I'm going to have to run some cables possibly right over the vent and I'd prefer not to have hot spots in the wires.

 

[Jackula]

Thank you, Fred! Kingwa had told me NOS and OS0 are not the same, but I don't think he gave any details. I wonder if anybody in this thread who speaks Chinese could contact Kingwa and get us some details on this. I would be interested to know more.

On another topic related to the DI-20HE, can anybody recommend a heat shield wrap for cables that does not pose any health risks (i.e. no fiberglass etc.) I'm going to have to run some cables possibly right over the vent and I'd prefer not to have hot spots in the wires.

The difference is filtering. On OS (and OS0) digital filters are used. On NOS analog filters are used. This was Kingwa's response to me from 2 years' ago:

The digital filter roll off depend on the input sampling. There is the digital filter follow the input sampling, like 44.1K, the roll off is on 20.5K. 96K roll off is on 43K. 192K roll off is on 86K.

There are a -6DB/OCT analog filter on the output stage , roll off is on 70K /-3DB. If the input sampling is over 192K, the 84K roll off around -9DB.
If the input sampling is not over 96K, the TDA simulate disable, the 84K roll off is over -130DB.

 

[gimmeheadroom]

Thanks @Jackula , amazing info!

 

[gimmeheadroom]

Guys, the Wireworld Chroma 7 cables seem hard to find in the EU. I see some Chroma 8, has the 7 series been replaced? Even with the 8 I'm not sure there is an HDMI cable.

I'm considering this one from Chord https://mp3store.pl/kable/hdmi/chord/2019030127232211301//chord-kabel-hdmi-c-view-075m which is not expensive and I hope it would be good coming from Chord. Any recommendations around this price (+-40 euros) would be appreciated.

 

[tonedeafmelomaniac]

The r2r 11 mkii does no digital processing. It uses only anlog filtering.

The difference is filtering. On OS (and OS0) digital filters are used. On NOS analog filters are used.

So, as far as I understand, NOS implementations in r2r-11 mk2 and r-1, r28, etc are the same.