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Gustard U12 USB Interface 8 Core XMOS chip - Page 81  

post #1201 of 3655

Hi All,

 

 

Today my MX-U8 has been ordered thru my kindest middleman ever, hpgsemaj.

He has helped me a lot communicating with Melodious and has arranged that i receive MX-U8 with better Noratel transformer (230V only)

and Crystals placed on sockets (pins) for making changing to NDK's a lot easier.

 

Again, hpgsemaj, lots and lots of thanks, you are the best! :bigsmile_face:

 

In the meantime I ordered the needed NDK Crystals, MUR120 rectifiers, several RIFA MKP 0,01uF/0,1uF bypass caps and Panasonic FC's (4700uF and 2700uF)

Can't wait to receive MX-U8 and starting all the mods :bigsmile_face:

 

Hope it will at least sound as good as my U12, if it is I'm a happy man :wink_face:

 

 

Finally, if XM-U8 is indeed at least equal to SQ U12, i will sell heavily modded U12 to anyone who's interested (yes, including the NDK's)

 

 

Happy modding for everyone :beerchug:

Alex

post #1202 of 3655

oh dear, I am flattered. :beerchug:

post #1203 of 3655
Quote:
Originally Posted by hgpsemaj View Post

oh dear, I am flattered. beerchug.gif

Would you help a European too? redface.gif
post #1204 of 3655
Quote:
Originally Posted by conquerator2 View Post


Would you help a European too? redface.gif

 

Thats what i thought would happen :wink_face:

I'm European too (Dutch)

post #1205 of 3655
Quote:
Originally Posted by abartels View Post
 

 

Thats what i thought would happen :wink_face:

I'm European too (Dutch)

 

 

 

Man and places are divided by north and south;

In search of High Fidelity are never divided by west and east.

 


Edited by hgpsemaj - 4/14/15 at 5:40am
post #1206 of 3655
Quote:
Originally Posted by hgpsemaj View Post
 

 

 

 

Man and places are divided by north and south,

In search of High Fidelity are not divided by west and east.

 

 

Thats a good one :beerchug::wink_face:

post #1207 of 3655

Finally, my MX-U8 arrived.  The DAC display shows 44.1kHz, but DSD128 was played back (the right lamp "DSD" is on).  Something must be wrong with the Ethernet cable I made for I2S/DSD connection.

The sound is perfect with the highest clarity I have ever experienced.

 

 

post #1208 of 3655
Quote:
Originally Posted by rb2013 View Post
 


I wounder if you ask him if he tests the clocks he buys for timing accuracy and jitter before installing? 

 

My second MXU8 is on the way and the Crystek clocks and FC caps are in - so will begin the mods once the 2nd one arrives.

 

Mr. Google translates it as: 

 

Mr, Liu Feng claims: Clock accuracy of the test done at the factory, this is my personally getting goods to Shenzhen. And, each version of the board to do a jitter test, not every machine are measured, jitter test is completed in my friend over there.

post #1209 of 3655
Quote:
Originally Posted by rb2013 View Post
 


Thank you!  I already have the parts and can easily handle these simple mods - and reverse them if the sound is not improved.

 

But for other's not so well versed in weilding a soldering iron - what would he charge and how long would it take?  Could make the same model with an external clock connection feature like the Tanley?

 

Mr. Google translates it as:

 

Mr. Liu claims: We are not planning to build external clock connection.


Edited by hgpsemaj - 4/14/15 at 7:42am
post #1210 of 3655
Thread Starter 
Quote:
Originally Posted by abartels View Post
 

Something about Jitter: http://www.ndk.com/en/ad/2013/001/index.html

 

 

 

 

 


Good post - but 'Phase Noise' is just one aspect of jitter and timing issues:

 

http://www.sitime.com/support2/documents/AN10007-Jitter-and-measurement.pdf

2. Types of Jitter
Jitter can be measured in a number of ways; the following are the major types of jitter:
• Period Jitter
• Cycle to Cycle Period Jitter
• Long Term Jitter
• Phase Jitter
• Time Interval Error (TIE)

 

PS And I previously posted all these measurements are just an average of sampled production units.  What I'm concerned about is the std dev from the mean in the actual clock you recieve to install.  I would love to see their QC statistics for a large sample size.

 

 

Even for an individual clock the amount of samples increases the Sigma

 

Quote:
 2.1.2 Calculating Peak to Peak Jitter from RMS Jitter Because the period jitter from a clock is random in nature with Gaussian distribution, it can be completely expressed in terms of its Root Mean Square (RMS) value in pico-seconds (pS). However, the peak-to-peak value is more relevant in calculating setup and hold time budgets. To convert the RMS jitter to peak-to-peak (Pk-Pk) jitter for a sample size of 10,000, the reader can use the following equation: Peak-to-peak period jitter = 7.44 x (RMS jitter) Equation 1 For example, if the RMS jitter is 3 pS, the peak to peak jitter is ±11.16 pS. Equation 1 is derived from the Gaussian Probability Density Function (PDF) table. For instance, if the sample size is 100, 99 of those samples will fall within ±2.327σ from the mean value of the distribution, only 1 sample, on average, will fall outside that region. SiTime measures the RMS period jitter over a sample size of 10,000 as specified by the JEDEC standard.

For example from the SiTime WP:

 

Sample Size Sigma (σ)

 

10 ±1.282

100 ±2.327

1,000 ±3.090

10,000 ±3.719

100,000 ±4.265

1,000,000 ±4.754

10,000,000 ±5.200

100,000,000 ±5.612

1,000,000,000 ±5.998

10,000,000,000 ±6.362

100,000,000,000 ±6.706

1,000,000,000,000 ±7.035

 

Table 1. Gaussian probability density function (PDF)


Edited by rb2013 - 4/14/15 at 8:01am
post #1211 of 3655
Thread Starter 
Quote:
Originally Posted by hgpsemaj View Post
 

 

Mr. Google translates it as: 

 

Mr, Liu Feng claims: Clock accuracy of the test done at the factory, this is my personally getting goods to Shenzhen. And, each version of the board to do a jitter test, not every machine are measured, jitter test is completed in my friend over there.

Thanks!

 

Quote:
Originally Posted by hgpsemaj View Post
 

 

Mr. Google translates it as:

 

Mr. Liu claims: We are not planning to build external clock connection.

Thanks again!

 

After studying the Tanley's inovative design (FPGA FIFO buffer and isolation) - I may give one a go.  I like the external clock feature- as there are some reasonable rubidium clocks available.  They also offer a SPDIF 3 feature that allows the clocks to be run as either Master or Slave

 

Quote:
 SDIF-3 function is a customized feature,the word clock of SDIF-3 can be slave or master. if you need SDIF-3 function, please contact seller.
Quote:
SDIF-3 functions available firmware , SDIF-3 clock output , external clock , you can add the switch selection. Client interface has been modified to function with SDIF-3 . These pictures are very grateful customers .
post #1212 of 3655
Quote:
Originally Posted by rb2013 View Post
 

Thanks!

 

Thanks again!

 

After studying the Tanley's inovative design (FPGA FIFO buffer and isolation) - I may give one a go.  I like the external clock feature- as there are some reasonable rubidium clocks available.  They also offer a SPDIF 3 feature that allows the clocks to be run as either Master or Slave

 

 

 

I have a brief contact with 'tanly_tech' of tanlyAudio yesterday, he told me the external clock sdif-3 is designed for accommodate 44. 1KHz. And, 45.158 and 49.152 are designed to control the main circuit board.

post #1213 of 3655
Thread Starter 
Quote:
Originally Posted by hgpsemaj View Post
 

 

 

I have a brief contact with 'tanly_tech' of tanlyAudio yesterday, he told me the external clock sdif-3 is designed for accommodate 44. 1KHz. And, 45.158 and 49.152 are designed to control the main circuit board.


I was thinking you could set the DAC to Slave it's clocks as the Tanley Master.  If it had an external clock hookup

post #1214 of 3655
Quote:
Originally Posted by rb2013 View Post
 


I was thinking you could set the DAC to Slave it's clocks as the Tanley Master.  If it had an external clock hookup

It's really a new topic for me. 'tanly_tech' of tanlyAudio claims if you connect 'tanly usb interface' to your DAC via XLR, then you don't need to hook up the external clock.  :confused_face: 


Edited by hgpsemaj - 4/14/15 at 9:25am
post #1215 of 3655

What does that mean?? USB in to Tanly and AES/EBU from Tanly to DAC?

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