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post #406 of 425
Quote:
Originally Posted by digger945 View Post





 The fact that it handles more than one sample rate says that it would be sensitive to changes in the input.


Exactly the WM8805 didn't make it to production with a VXCO integrated synchronous PLL as the orginal design team had hoped,  and the 50 ps number is its intrinic jitter,  ie output jitter is greater than or equal to intrinsic jitter.  Its just another digital receiver nothing special.
 

post #407 of 425

 

Originally Posted by digger945 View Post

 

The fact that it handles more than one sample rate says that it would be sensitive to changes in the input.


we can see that WM8805 has its own dedicated 12Mhz PLL: http://www.littledot.net/forum/viewtopic.php?f=9&t=814

 

here we can read "Advanced jitter attenuating PLL with low intrinsic period jitter of 50 ps RMS. / S/PDIF recovered clock using PLL / Supports 10 – 27MHz crystal clock frequencies / Generation of all typically used audio clocks is possible using the high performance internal PLL": http://www.wolfsonmicro.com/products/spdif_transceivers/WM8805/

 

It seems rather obvious that the WM8805 chip in his DAC is "coloring"(fixing?) the hiface output. The littledot ppl explained on their forum that WM8805 is also active on the USB input and outputs I2S directly to the DAC chip.

 

PS: some ppl give the hiface for 175ps jitter, and some others for 284ps: http://www.computeraudiophile.com/content/M2Tech-hiFace-Asynchronous-USB-SPDIF-Converter-Review


Edited by leeperry - 10/6/10 at 7:40am
post #408 of 425



 

Quote:
Originally Posted by leeperry View Post

 


we can see that WM8805 has its own dedicated 12Mhz PLL: http://www.littledot.net/forum/viewtopic.php?f=9&t=814

 

here we can read "Advanced jitter attenuating PLL with low intrinsic period jitter of 50 ps RMS. / S/PDIF recovered clock using PLL / Supports 10 – 27MHz crystal clock frequencies / Generation of all typically used audio clocks is possible using the high performance internal PLL": http://www.wolfsonmicro.com/products/spdif_transceivers/WM8805/

 

It seems rather obvious that the WM8805 chip in his DAC is "coloring"(fixing?) the hiface output. The littledot ppl explained on their forum that WM8805 is also active on the USB input and outputs I2S directly to the DAC chip.

 

PS: some ppl give the hiface for 175ps jitter, and some others for 284ps: http://www.computeraudiophile.com/content/M2Tech-hiFace-Asynchronous-USB-SPDIF-Converter-Review


As you know all digital recievers use a pll even my 1992 CS8412,  but Wolfson's is "Advanced".   I have heard the Mface reported to be tested at under 20 ps.  I would imagine the issue with the LD is jitter at the S_D DAC chips induced by the power supply which is masking transport changes but maybe it is the advanced PLL.    Regardless pairing a Hiface to a LD DAC is not money spent wisely IMHO.

 

 

 

 

 

 

 


 

post #409 of 425

 

Originally Posted by regal View Post


all digital recievers use a pll even my 1992 CS8412,  but Wolfson's is "Advanced" 

 

the WM8804/8805 are S/PDIF transceivers/reclockers, not mere receivers. They recover the clock, discard it and output a new one via I2S..rated at 50ps. Those 2 chips are indeed bad news for all the uber-low jitter transports coz they render them more or less useless. I see that the Teradak Chameleon and Twisted Pear gear are also using one, it's nice to see a trend here.

  

Originally Posted by regal View Post

I have heard the Mface reported to be tested at under 20 ps. 

 

Through the gravepine? Can you identify 20ps and 50ps jitter by ear? Even the AP gear cannot measure <100ps.
  

Originally Posted by regal View Post

 

pairing a Hiface to a LD DAC is not money spent wisely


Yes, you told us already, we should buy obsolete DAC's from A-GD.


Edited by leeperry - 10/6/10 at 9:39pm
post #410 of 425
Quote:
Originally Posted by leeperry View Post

 

 

the WM8804/8805 are S/PDIF transceivers/reclockers, not mere receivers. They recover the clock, discard it and output a new one via I2S..rated at 50ps. Those 2 chips are indeed bad news for all the uber-low jitter transports coz they render them more or less useless. I see that the Teradak Chameleon and Twisted Pear gear are also using one, it's nice to see a trend here.

  

 

Through the gravepine? Can you identify 20ps and 50ps jitter by ear? Even the AP gear cannot measure <100ps.
  


Yes, you told us already, we should buy obsolete DAC's from A-GD.

 

You sound like you are really convinced by Wolfson's marketing ads on the WM8804,  but you don't know the whole story it seems.  You do understand that their PLL drops off at 100hz?   So any and all jitter in the bass region where it is most critical passes right thru.  So your 50ps receiver can pass 5 nS of jitter .  Just trying to help you make sense of the datasheets.  Its also been in production since 2009 and hasn't changed the world,  nor will it ever.

 

post #411 of 425

Hi Regal I know this is an old thread but ive just bought  a Hiface from ebay, it has the small clock.

 

Just to be clear on this:

 

Is It an inferior batch and sounds bad due to the small clock or is it because I'm using it with a Valab dac with a chip that makes it usless..???

post #412 of 425

 

Quote:
Originally Posted by Audioalan View Post

it has the small clock.


How do you know? Have you x-rayed it? 

post #413 of 425

 

Originally Posted by Sebhelyesfarku View Post

 


How do you know? Have you x-rayed it? 

casse%20noix%20design.jpg  [:eerilie]

post #414 of 425
Quote:
Originally Posted by leeperry View Post

 

[:eerilie]

u15365664.jpg
 

post #415 of 425

WE'RE UNDER ATTACK...oh wait it's just a lemon juicer.

post #416 of 425

No its a drone from Italia sent to install small clocks in your Hiface.

 

I figured this thread has run its course.

post #417 of 425

 

Quote:
Originally Posted by regal View Post
I figured this thread has run its course.


No, you have to wait until I got my new hiFace x-rayed. I've already found a provider who makes industrial x-rays about electronics. MWUAHAHA


Edited by Sebhelyesfarku - 10/8/10 at 12:09am
post #418 of 425
Quote:
Originally Posted by Audioalan View Post

Hi Regal I know this is an old thread but ive just bought  a Hiface from ebay, it has the small clock.

 

Just to be clear on this:

 

Is It an inferior batch and sounds bad due to the small clock or is it because I'm using it with a Valab dac with a chip that makes it usless..???


Why did you buy a smallclockedFace?

 

In any event, you might see if you can send it back to m2tech for an exchange. 

 

They exchanged mine, and the largeclockFace sounds better than the smallclockFace, but as Regal has said, the stockFace needs to be modded to operate on battery power before it sounds good.

 

USG

post #419 of 425

The seller claimed it was only 3 months old..turned out it aint and I'm trying to get my money back..

 

The supplier is also claiming to know nothing of this problem, PuriteAudio in the uk.

 

As soon as I plugged it In I knew something wasn't quite right with it..

 

post #420 of 425
Quote:
Originally Posted by Audioalan View Post

The seller claimed it was only 3 months old..turned out it aint and I'm trying to get my money back..

 

The supplier is also claiming to know nothing of this problem, PuriteAudio in the uk.

 

As soon as I plugged it In I knew something wasn't quite right with it..

 


How did you determine it was more than 3 months old?   ........... just curious.

 

USG

 

Edit to fix spelling


Edited by upstateguy - 10/8/10 at 9:48pm
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