[bButcher]

NOS7 is of asynchronous structure, it use internal 98Mhz or its derived clocks instead of external source clock.
 
(1) J1 {PLLEN}, J2 {ATT0}
Master clock
98 Mhz - [On, On], [Off, Off]
196 Mhz (PLL1) - [On, Off]
294 Mhz (PLL2) - [Off, On]
 
(2) J4 {IPS0}
NOS Mode 1 [Off] - simple first order low pass filter
NOS Mode 2 [On] - very long impulse response FIR low pass filter
 
(3) J5 {IPS1}
[Off] - neutral
[On] - even smoother
 
(4) J6 {DITH}
Asynchronous mode - how it synchronizing (to external clock)
[Off] - default
[On] - enhanced mode - for lesser (noisy, more jitter) external source
 
(5) J7 {BYPASS}
[On] - default
[Off] - bypass all functions of  DSP-1, with exceptions of extracting I2S left/right channel data and distributing to corresponding PCM1704 chips. This will put dac back to synchronous structure. Still support up to 768k sampling rate.
 
So to connect to SU-1, no additional setting is needed. Also strongly recommend trying BYPASS mode, SU-1 will really show its potential in this setting.

 

[remoss]

A question though: i have a AGD Nos 7 and i hear a rather loud noise when i switch between music numbers. Is this normal?

I switched from a SPDIF source to a I2S source and the noise is totally gone now. Also the sound greatly improved with that switch, so i'm  happy

 

[Mahdi8]

Been enjoying the new lease in life of my Ref7s after modifying to NOS and installing amanero. Running it through raspberrypi running picoreplayer has even brought it to a whole different level compared to Windows running foobar using ASIO. 
 
Anyone else using raspberry pi for their NOS7? I even wonder if going direct I2S from raspberry pi directly to NOS7 bypassing USB completely will be any better. has anyone tried this?

 

[JaMo]

I am also using Raspberry Pi's via Amanero Combo384 with both NOS-7 and my NOS-11. I also found that the performance was far better in the Raspberry Pi's than in my case the Logitech Squeezebox Touch. I use both RPi2B's and RPi3B's with similar soundquality in this setup (RPi-Amanero-dac)
 
I haven't been testing to get I2S direct to dac yet but have had it in mind for a while. In fact I have forgot to do because the already fantastic sound. But I will do it some time. If You will do it in near time I am very intrested in Your findings.
 
/Jan
 
(ps. I also feed my ESS9018 dac's this way. It allows playing DSD-material with an excellent result)

 

[Mahdi8]

when installing amanero I found out that the DSP1 doesn't need a masterclock so theoretically it should work considering the wiring from amanero board to the DSP1 board is only BCK,LRCLK, DATA, Ground so pretty much matching the Pi i2s output

@Jamo did you wire your 9018 dac similarly is it AudioGD dac also?

 

[JaMo]

@Mahdi8: Yes, my ES9018dac's are Audio-gd's. I have the NFB27H and NFB28 (2016). It is very easy to feed their newer models now with the RJ-45 I2S-inputs/channels.
 
Now when we talked about this direct "RPi - I2S - dac". I actually did this testing today, a moment ago. Couldn't resist(!)
 
The I2S-direct sounds equal to the Amanero-input to my ears. Nothing more or less...just the same very high quality sound.
 
 
With the es9018 dac's I loose the DSD-ability going with I2s-direct.
 
 
So to wrap my findings up....Yes, You can save Your money not buying the Amanero-card and feed with I2S-direct with the PCM1704-dac's.
 
And if You don't care for DSD-material You can do the same with the ESS-dac's.
 
I will stick to my Amanero-inputs in my ESS-dac's but may use I2S-direct on the PCM's..I will test it for a while to see if things matures
 
/Jan

 

[Mahdi8]

Awesome Jam will give it ago also. Btw mind sharing your amanero config in picoreplayer? With just setting to USB to amanero has clicks in playbay for me but manage to reduce it significantly by setting buffer to 6000:4000. But sometimes I can still here clicks. Quite rare though.

I'm still using first gen pi. Will upgrade to pi2 if that makes a difference

 

[motberg]

iancanadaTT at Twitter (iancanada at diyaudio) has been working on a Raspberry Pi I2S/DSD isolator HAT with native DSD decoder for a few months now...
he seems to offer pretty much SOTA solutions for the Pi from what I have been reading, but since I have no DIY skills I am waiting patiently for this HAT development...

 

[JaMo]

We are a bit off topic now. But here we go..
 
In PiCorePlayer (I use the latest build 2.06), Squeezelite Settings: 
 
Audio Output: " USB audio "
 
Output Settings: " front:CARD=Amanero,DEV=0 "
 
Log level setting: " none "
 
Device supports DoP: " -D "
 
The rest of the boxes should be kept empty. My PiCoreplayers runs flawlessly without any pops or noise. 
 
@motberg Thanks for the info.
 
/Jan

 

[Mahdi8]

Thanks Jan back to the topic now I'm using nos mode 2 ips1 on and dith on. I found it to be the best match with my susy dynahi and hd800. The bass on it so addictive hd800 has never felt so fun and enjoyable and still remain the high detail level

 

[FredA]

For owner of Singxer F-1, this might be interesting; In the first few hours while burn-in NOS-11, F-1 made a big improvement over the built-in Amanero, with more burn-in time the advantage gradually diminish; now the NOS-11 has way pass 600 hrs, the two are virtually indistinguishable - even using I2S for F-1. This is not so surprising, since Async/FIFO architecture in NOS-11 is supposed to be more immune to clock jitter. So the last trump left of F-1 is galvanic isolation, to fully take advantage of it I first remove the isolation/switching 5V power (Mornsun B0505S) which will generate 100mV noise in the isolation section, then use NOS-11's 3.6V (unplug Amanero from socket) to drive the isolation section. To make sure 3.6V is high enough, the generic 3.3V LDO is replaced by ADP150 (9uV rms); along the way I also replace the same generic 3.3V LDO for XMOS;

Well, the result - improved micro-dynamics!

Interesting mods. So i suppose the f-1 sits inside your dac...? Interesting also to hear that jitter rejection seems excellent. Would you recommend going from master-7 to nos7 using nos2 mode as i would like to try?

 

[bButcher]

Interesting mods. So i suppose the f-1 sits inside your dac...? Interesting also to hear that jitter rejection seems excellent. Would you recommend going from master-7 to nos7 using nos2 mode as i would like to try?

Yes, it occupy the space amanero used to have.
 
"Jitter rejection" in Kingwa's sense is very good, even Raspberry I2S will perform equally well as amanero according to JaMo's experiment. --- refer to "https://volumio.org/forum/sound-quality-limitations-raspberry-i2s-dacs-t2391.html" for raspberry's jitter performance. That basically means Kingwa have implement the Async/FIFO right, so input interface's "jitter" matter little now. The output jitter performance still will be dominated by its internal clock jitter. Kingwa's reply always need reinterpretation in my experience. The post you refer to is before I change to BYPASS mode, so the improvement F-1 has is because of galvanic isolation, similar to JoMo and other's moving from noisy computer to far less noisy Raspberry usb output or using Intona.
 
The real game changer for me is when I change to BYPASS mode and let F-1's femto clocks start to work its wonder. Now I have 3D soundstage and more.
 
You can try Mode 2, it seems lot of people like it, but be prepared you will lose some PRaT.
 
Personally I will stick to BYPASS mode and do oversampling or low pass filters on computer. And I listen to a lot high resolution music - most 352k, so BYPASS just suit me fine.

 

[FredA]

  Yes, it occupy the space amanero used to have.
 
"Jitter rejection" in Kingwa's sense is very good, even Raspberry I2S will perform equally well as amanero according to JaMo's experiment. --- refer to "https://volumio.org/forum/sound-quality-limitations-raspberry-i2s-dacs-t2391.html" for raspberry's jitter performance. That basically means Kingwa have implement the Async/FIFO right, so input interface's "jitter" matter little now. The output jitter performance still will be dominated by its internal clock jitter. Kingwa's reply always need reinterpretation in my experience. The post you refer to is before I change to BYPASS mode, so the improvement F-1 has is because of galvanic isolation, similar to JoMo and other's moving from noisy computer to far less noisy Raspberry usb output or using Intona.
 
The real game changer for me is when I change to BYPASS mode and let F-1's femto clocks start to work its wonder. Now I have 3D soundstage and more.
 
You can try Mode 2, it seems lot of people like it, but be prepared you will lose some PRaT.
 
Personally I will stick to BYPASS mode and do oversampling or low pass filters on computer. And I listen to a lot high resolution music - most 352k, so BYPASS just suit me fine.

Thanks.
 
There is just one thing  that is confusing: Kingwa told me the pll could be turned with both nos mode. What do you think he means by it? As you mentioned, I also want full benefits of the femto clocks.

 

[gk2013]

  NOS7 is of asynchronous structure, it use internal 98Mhz or its derived clocks instead of external source clock.
 
 
 
 
 
(2) J4 {IPS0}
NOS Mode 1 [Off] - simple first order low pass filter
NOS Mode 2 [On] - very long impulse response FIR low pass filter
 
(3) J5 {IPS1}
[Off] - neutral
[On] - even smoother
 
(4) J6 {DITH}
Asynchronous mode - how it synchronizing (to external clock)
[Off] - default
[On] - enhanced mode - for lesser (noisy, more jitter) external source
 
(5) J7 {BYPASS}
[On] - default
[Off] - bypass all functions of  DSP-1, with exceptions of extracting I2S left/right channel data and distributing to corresponding PCM1704 chips. This will put dac back to synchronous structure. Still support up to 768k sampling rate.
 
So to connect to SU-1, no additional setting is needed. Also strongly recommend trying BYPASS mode, SU-1 will really show its potential in this setting.

 
Just out of interest, what do you mean with this? Did Kingwa confirm this?
(1) J1 {PLLEN}, J2 {ATT0}
Master clock
98 Mhz - [On, On], [Off, Off]
196 Mhz (PLL1) - [On, Off]
294 Mhz (PLL2) - [Off, On]
 
Even more interesting is removing the Bypass jumper. I cannot find this setting on Audio-GD website. Was this confirmed by Audio-GD?
 
Thank you

 

[bButcher]

  Thanks.
 
There is just one thing  that is confusing: Kingwa told me the pll could be turned with both nos mode. What do you think he means by it? As you mentioned, I also want full benefits of the femto clocks.
 
So it seems that

(1) J1 {PLLEN}, J2 {ATT0}
Master clock
98 Mhz - [On, On], [Off, Off] --- directly use TCXO 98.304MHz clock, clock jitter would be determined by 98.304 XO's quality
196 Mhz (PLL1) - [On, Off] --- use Cyclone's PLL function to multiply the input clock by 2, clock jitter would be determined by PLL jitter performance (200ps max according to Cyclone's spec)
294 Mhz (PLL2) - [Off, On]--- use Cyclone's PLL function to multiply the input clock by 3, clock jitter would be determined by PLL jitter performance (200ps max according to Cyclone's spec)
 
Master clock is used to drive the low pass filter and generate BCLK, WCLK and DATA for 1704s.
 
refer to "http://www.audio-gd.com/Pro/NOS/NOS7/NOS7EN_Use.htm"
In mode 1, you can use either PLL, in mode 2 you can only use PLL1 cause the FIR filter take too much computation power.
 
Default is PLL off; No matter which one you choose, the jiiter performance just can't compare to a femto clock.
 
 

   
Just out of interest, what do you mean with this? Did Kingwa confirm this?
(1) J1 {PLLEN}, J2 {ATT0}
Master clock
98 Mhz - [On, On], [Off, Off]
196 Mhz (PLL1) - [On, Off]
294 Mhz (PLL2) - [Off, On]
 
Even more interesting is removing the Bypass jumper. I cannot find this setting on Audio-GD website. Was this confirmed by Audio-GD?
 
Thank you

About PLL, please refer to "http://bbs.audio-gd.com/dispbbs.asp?boardid=2&Id=30056&page=2"
It's audio gd's Chinese forum, sorry it is in Chinese.
 
About Bypass, Audio-gd won't recommend anyone use it; By email exchange with Kingwa, he just told me all functions will be disabled and after doing some testing it's easy to find out the rest.
Actually if you disconnect the 98Mhz XO or just cut off its power, the DSP-1 will automatically enter BYPASS mode.