[hugoboss]

Audio GD , The Master 7 Monster 8PCS PCM 1704 DAC , have achieve many good reputation in many reviewer.
with so many revision from the usb port.
from usb32 to u8, now new Amanero. every usb change make the sound more and more better.
In 2016 , Audio GD Released It's New NOS 7 DAC.
With New DSP Software design
Two option NOS modes, support up to 768KHz input,
Asynchronous clock , FIFO data process.
Built in 8 PCM1704UK.
 
 
 
The Different between Master 7 and the new NOS 7 in Audio Gd website

          The Master 7 had the 8X times oversampling and NOS mode can be selection .
          The NOS 7 had the more advantage algorithm   than the NOS mode of the Master 7 .
          The oversampling design and NOS design had different sound characteristic ,it is not which is better but    depend on customer prefer
     
 
 
I never ever hear any nos or R2R DAC in my audio journey before.
When searching for a Nonsampling Dac or Nos or R2R DAC ,
I found These New NOS DAC , I ordered it directly from China , after many question with The Man Behind this Awesome DAC        "MR KingWa"
the funny thing is Kingwa Once asked me . "If i really want this Nos Dac, Because the sound maybe not what iam looking for"
these question make me more curious about this nos 7.
in my audio journey , iam never ever try a nos dac. my all dac collection is all delta sigma dac from Centrance Mini,Aune X1 ,Aune S16, except Chord Hugo.
So the Time is just so Right When this New Nos 7 released i think i will try it.
I heard so many comments in headfi from some master 7 owner that the master 7 sound is so organic, so natural, these is the reason that make me want to try,
What is organic, natural, sound people are talking about!
 
 
 


The Input in the back, i ordered the HDMI I2S port
 
BNBNC input, up to 24bit / 96KHz
AES input,  up to 24bit / 192KHz
RCA coaxial input,  up to 24bit / 192KHz
optical input , up to 24bit / 96KHz
I2S input, ,up to 32bit / 384KHz
USB input,  ,up to 32bit / 384KHz
 

 
 

from left to right:
Cayin A88T MK2, IFI Micro IUSB 3.0. 5V Linear Power Supply, Singxer F1 DDC USB to Coax, Dual Head DIY USB Cable OCC copper for data , pure silver for Ground And Power
 
 
Hardware Setup
1. Pc Computer intel I7-4790K as source , foobar as player with asio output audio file mostly flac 16 bit 44khz loseless
2. IFI Micro IUSb 3.
3. F1 DDC Usb to coax
4. Cayin Tube Amp with 4 PSVane KT88 T2, 2Shuguang Black Treasure 6SL7 and 2 Shuguang CVT181-T
5. DIY Dual Head USB Cable with occ and silver gold cable
6. PSB Synchrony Two B Speaker
 
I will do several Test with different Input and DDC.
First I will try Usb Port Straight From Pc with dual head usb cable plus linear psu ,
Second will try it with IFI Micro IUSB 3.0 in chain
Third will try with a new DDC usb to coax "F1-Singxer Xmos 208 Usb to coax"
Last will try with IFI Micro IUSB 3.0 And F1 Combo
 
 
i will update later the listening test . just wait . music for test
 

 
 
iam a vocal lover most of the test with album from chinese female singer "Lei Ting"

 

[hugoboss]

NOS 7 have 2 Nos mode for user to select here is the picture of the jumper setting from audiogd web
 
One is the best speed data process,
The Other One is applied large algorithm to process the data.
 
In the design had applied -6db /oct passive analog filter , you can hear the wonderful sound of the NOS but you can't hear the noise as other some NOS design .
 

 
 
 
Listening Impression using Nos Mode 1
 
 
1. From USB Port From PC  To NOS 7 USB
 
The Sound Is So Relaxed, very comfort to my ear without any fatique, Neutral, A Little Dark, Very Clear and balance.
the sound of instrument is just like other said , Natural, and so Balanced. the most balance dac i ever heard.
The Treble never feel Harsh it's just make me feel so relaxed to listen to female vocal sound.
if i can describe the sound is just like this pic

 
Dynamic = i feel my delta sigma dac have more dynamic or more attack in treble and bass but feel a little harsh.
 
 
 
2. From USB Port From PC  To IFI MICRO IUSB 3.0 TO NOS 7 USB
 
The Sound still feel Relaxed , comfortable and natural .
a little improvement but not so different with NOS 7 Own USB.
i think this because NOS 7 have it's own very good 5 volt power for usb, so it don't need power from pc dirty usb power.
 
 
3. From USB Port From PC  To F1 DDC USB TO COAX (XMOS NEWEST XU-208 CHIPSET) TO NOS 7 COAX
 
This is the best connection i heard compared to 2 above.
all the details, dynamic, got boosted. the difference is instantly can heard, not subtle.
it becomes more airy. very extended treble, vocal have more intimacy.
just like the dac got steroid injected. more power, dynamics, and details, without harsh
 
 
Now About Firmware Upgrade.
Kingwa Told Me that Nos 7 firmware can be updated to newest firmware ,
using usb blaster hardware and altera software.
you got this software update everytime there is new firmware update from audio gd.
so a very good support from audiogd.
 
you need this device called usb blaster , you can buy at taobao china online store

 
 
 
will post my final conclusion later,
will do the nos mode 2 in final test! thanks
 
 
 
Listening Impression using Nos Mode 2
 
here is the jumper i put in nos mode 2
there is other jumper setting i am not yet test

 
 
 
1. From USB Port From PC  To NOS 7 USB
 
Detail, OmG I hearing just what currawong said in his review on audio gd master 7
there is some far distance detail like cymbal, violin, people murmuring something SCARRY! (I thought i just broke something in the dac or my amplifier). but it's not after several testing same song, i found this is a sound from the song i never heard before using centrance, aune s16, even chord hugo.
so nos mode 2 in my hearing there is some far distance detail maybe you never heard before will be revealed with NOS 7!

 

[yates7592]

Very much looking forward to your impression of the difference in sound between mode 1 and mode 2 on this dac.

 

[hugoboss]

soon, actualy i still waiting for the new firmware update for nos 7 and the usb blaster (the hardware requirement for updating the new firmware in nos series) to arrive then doing some test again with nos1 and nos2 mode. i will update again soon.

 

[JaMo]

Hi Hugoboss, 
 
Thanks for Your early impressions and Your comparisons with the Delta-Sigma Dac's.
 
Please be aware of the need for the quite significant burn in-time of the Audio-gd gear. Approx. 500h will be enough to settle and stabilize the electronics. 
 
The two different NOS-modes should be very intresting to hear Your verdicts on.
 
 
 
In my case, I look forward to perform this NOS-upgrade on my Master-7.  and I also suffer the "waiting mode" for the delivery of an USB-blaster.
 
/Jan

 

[hugoboss]

hi Jamo
i have done listening nos mode 2, now it's around 100 hours in burning
the difference is the freaking detail, i can hear some
far distance detail like cymbal, violin, people murmuring something SCARRY! (I thought i just broke something in the dac or my amplifier). but it's not after several testing same song, i found this is a sound from the song i never heard before using centrance, aune s16, even chord hugo.
so nos mode 2 in my hearing there is some far distance detail maybe you never heard before will be revealed with NOS 7!
so far i like nos 2 mode better then nos 1

 

[JaMo]

Hi Hugoboss!
 
It sounds very promising..
 
Can You say anything about soundstage? Do You feel it delivers high-end music reproduction?
 
/Jan

 

[hugoboss]

  Hi Hugoboss!
 
It sounds very promising..
 
Can You say anything about soundstage? Do You feel it delivers high-end music reproduction?
 
/Jan

 
high end music = of course. for me the high frequency that doen't sound harsh, i sure it's high end.
sound stage = for 100 burning hour using the default usb input . i feel chord hugo  give more wider soundstage ,more 3d
but using IFI IUSb3 plus F1 (usb to coax ddc) NOS 7 almost there .
i keep burning the nos 7 to see the final result. one thing i very sure. the dynamic of nos7 is lost to chord hugo.
what iam like is the relaxed feeling from nos 7 and the natural sound, and somehow that little detail can somehow make me shocked .

 

[motberg]

  hi Jamo
i have done listening nos mode 2, now it's around 100 hours in burning
the difference is the freaking detail, i can hear some
far distance detail like cymbal, violin, people murmuring something SCARRY! (I thought i just broke something in the dac or my amplifier). but it's not after several testing same song, i found this is a sound from the song i never heard before using centrance, aune s16, even chord hugo.
so nos mode 2 in my hearing there is some far distance detail maybe you never heard before will be revealed with NOS 7!
so far i like nos 2 mode better then nos 1

Hi hugoboss,
Many thanks for taking the time and effort for these reviews... I agree with the others that my Master 7 seemed to improve during burn-in and finally stabilize after about 300 hours or so...
If you get the chance, please let us know about the Amanero USB vs. the F-1 RCA SPDIF when in nos mode 2...

 

[yates7592]

I have a brand new unopened NOS 7 for sale here:
http://www.head-fi.org/t/809025/audio-gd-nos-7-latest-nos-version-of-master-7-brand-new-unopened

 

[JaMo]

Hi all, 
So, I did the NOS-upgrade on my Master-7 as a tester, based on Audio-gd's advertised offering. The process was/is rather easy. So if You have some skills of soldering and are used to work with electronics in general, I think You should go for this upgrade and perform it Yourself. If You don't feel safe doing it, You should consider getting the help either from Audio-gd or from a more local helper.
 
Well I ordered the needed high quality/high stability TCXO from Audio-gd aswell as the USB-blaster from ebay. The software used was the one Audio-gd has a link to on their site. I followed the instructions and after the cutting- and soldering work I reprogrammed the Alter-CycloneII DSP with the new NOS-software from Audio-gd/Kingwa.
 
Up to now when writing this the NOS-7 has about 200 hours of burn-in-time. So I am very aware of the "Not yet fully burned in process!". And Yes, in my calculations I have about 40 percent before I get the full perforamnce.
In this/my case I have to be patient and wait for the new 98MHzTCXO to stabilize. I have owned the Master-7 for a few years and it has provided with approx. 3.5-4000h of service so the electronics has matured for sure and it is only the new TCXO I have to wait to get full service from. After more than 30 years of inventing, constructing and manufacturing audio-gear of various grades the higher grade audio gears I have work with sounds best after about 500 hours of burn in. This subject of burn in time needed or not..reappears now and then.. For me with my experience the 500h-mark is valid. Enough about that.
 
Back to the NOS-mod. 
I have a mix of audio-gd products to compare the NOS-7 to. The comparison stack contains Master-11 (4x PCM 1704uk), NFB-27H (ESS9018) and a NFB-28H(2016)(ESS 9018).
 
I use a pair of Master-2's poweramps and a couple of headphones, Hifiman HE-6 balanced, Sennheiser HD650 balanced, Fostex T50RP III modded and a few more.
 
Procedure: I use the M-11, NFB-27H and the NFB-28H2016 as preamps and as phoneamps. I have used the ACSS-cables between pre-poweramp. PiCorePlayers are used and are feeding the gear through USB (Amanero Combo384). Music material contains all kinds of qualities in Mp3, M4a, AAC, FLAC, WAV, AIFF and DSD-material in NFB-27,-28 (DSF, DIFF)
 
I also only use the NOS 2 setup during the complete burn in process. (When it has stabilized, I will do thorough compare between NOS 1 and 2)
So..
1. With the Master-11 I get a very good compare to the original characteristic of the DSP software. (I use 8 x oversampling). The NOS 2 is already clearer and has more details. The soundstage is more or less equal at this state. The laid back feeling or effortless performance are true for both.  
 
2. The NFB-27H is a ESS SABRE ES9018-chip based dac that delivers a crisp, clear and a bit dry music-picture. Very high level of control. Distinct bass. This comparison is is hard. I refer to NOS 2 and I say death race at this state. The actual difference is the effortless feeling in the NOS-7. The ESS-dac has it all but in some way it cost You energy to concentrate and 
listen... In the NOS-7, You don't have to "meet the sound".. It just flows beautifully through the air and You smile before You know it.
3. The NFB-28H (2016) is also based on the ESS ES9018 and it is a bit annoying to accept that the amplifying sounds better in the NFB-28H than in the bigger brothers M-11 and NFB-27H. Beside this fact, the result is identical to the ones for the NFB-27H.

This is not even "halfway" and the result so far is very promising. 
A. The performace is improved big time compared to the original DSP-programming.
B. The NOS-7 performs very good up my highest tests with 24/32 and 384KHz
C. When playing DSD-material synchronised on all players the NOS-7 is auto-muted. (Very good feature, Thank You Kingwa)
 
The burn in continues and I am waiting for the soundscape to open up more with more ambience feeling, more precise placing of instruments and details and last but not least, more soul and presence. It will come, I know...
 
To be continued.. 
 
Jan

 

[gk2013]

I posted the link also in the Master 7 thread. A review of the Master 7 vs NOS 7. http://hifi-opinions.com/en/review-audio-gd-master-7-dac-versus-nos-7-dac-2/

 

[xrobbo]

@JaMo
Hi Jan,
it is not fully clear to me whether for you the upgrade from M7 to NOS7 has or has not improved SQ.
I have myself a M7 and I'm considering doing the upgrade (Magna Hifi does it for a reasonable price).
Thanks for any information that would help me take the decision.

 

[JaMo]

Hi xrobbo,
The sound quality is already better in the NOS-7 despite the fact that the TCXO hasn't fully burned in yet. It means that it has not yet showed its full potential and also that it only will get even better than now.
 
I need about ten more days of burn-in-time before I have the final results regarding the performance.
 
Compared to Master-7 there is no hesitation from my pointof view. In my ears, the NOS-7 already sounds better than the Master-version. It also gives the ability to play higher resolution material. 
 
My advice: -Just go for the NOS-upgrade! It is absolutely a good choice.
 
/Jan 

 

[xrobbo]

  Hi xrobbo,
The sound quality is already better in the NOS-7 despite the fact that the TCXO hasn't fully burned in yet. It means that it has not yet showed its full potential and also that it only will get even better than now.
 
I need about ten more days of burn-in-time before I have the final results regarding the performance.
 
Compared to Master-7 there is no hesitation from my pointof view. In my ears, the NOS-7 already sounds better than the Master-version. It also gives the ability to play higher resolution material. 
 
My advice: -Just go for the NOS-upgrade! It is absolutely a good choice.
 
/Jan 

Many thanks.
A couple of additional questions:
are you using it via the usb port or through an external digital interface to i2s port?
do you upsample in the pc (eg. with a player like HQP) or do you just feed it with red book as it is?