The Well Tempered Master Clock - Building a low phase noise/jitter crystal oscillator

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I am sorry to bother you all, but I have - hopefully - a simple question. I recently started looking at class D amps and been trying to wrap my head around what I should look into for the master clock. Is this the right thread for doing so ??? - I am also planing a Shiga CD build, so for that project, this should be okay, but my question is as mentioned, for class D amp.

Many thanks in advanced.
 
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Hi Andrea,

Is it possible for you to modify and provide components value for SC-Cut 24Mhz and 25Mhz respectively? If it is possible, I will add myself for 5 x SC-Cut 24Mhz and 5 x SC-Cut 25Mhz on GB for PC motherboard and USB clock mod.


Cheers,

Ken

It's not a problem to calculate the components value for these frequencies, the real issue is to reach the MOQ requested for each frequency, at least 10 pcs and sometime 15 pcs, depending on the frequency.
 
I am sorry to bother you all, but I have - hopefully - a simple question. I recently started looking at class D amps and been trying to wrap my head around what I should look into for the master clock. Is this the right thread for doing so ??? - I am also planing a Shiga CD build, so for that project, this should be okay, but my question is as mentioned, for class D amp.

Many thanks in advanced.

I'm not an expert of class D amplifiers, but as far as I know they need lower oscillation frequency, kHz and not MHz, so then you need to divide down several times.
 
Xtal oscillator

/quote I am sorry to bother you all, but I have - hopefully - a simple question. I recently started looking at class D anps and been trying to wrap my head around what I should look into for the master clock. Is this the right thread for doing so ??? - I am also planing a Shiga CD build, so for that project, this should be okay, but my question is as mentioned, for class D amp. /unquote

This message has been sent to me by mail (automaticly??) with some presure that I HAVE TO answer to this question. Well, here I am....

For a class-D amp is no need for an Xtal-oscillator at all.

For an application to drive an ADC or DAC I developped long ago tge circuit as in the article:
https://by-rutgers.nl/PDFiles/rutgerS-Clock.pdf
Mind that an oven is never needed in these applications!
Good luck,
Herbert.
 
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Need advices please

Hi,

After some readings I would like to use two At-Cut Laptech on the Rasberry-Pi FifoPi board from Iancanada trough the TWMC-DIL adapatators.

My library is mainly old ripped Cds from the 80's & 90's and I assume most of them if not all are 16/44.1 RedBook: I would populate a Laptech At-Cut 5.6448 MHz on the first area of the FiFoPi XO area for this frequency.

I also have few 24/88 & 192 materials from online libraries and then my choice could be a Laptech At-Cut 24.576 MHz dedicated for them for the second area of the FifoPi.

Am I ok with that choice? I want something simple without oven so my choice of At-Cuts XOs despite knowing OCXO Sc-Cuts are better.

Related to my XOs choice above I would like please to know if there is a big SQ difference between the Colpitts-Clapp board and the Pierce board. From Andrea Mori's posts I'm believing the Pierce oscillator could be a little better without being sure of that.

Has anybody tried to use 3 pins LTO3042 ldo regs for the 15V & 3.3V directly on the Colpitt oscillator board to reach a better PSRR & noise result versus the main TWMC main power board ? Could it gives a better result than the Pierce witch regs are farer of the board ?
 
Last edited:
Hi,

After some readings I would like to use two At-Cut Laptech on the Rasberry-Pi FifoPi board from Iancanada trough the TWMC-DIL adapatators.

My library is mainly old ripped Cds from the 80's & 90's and I assume most of them if not all are 16/44.1 RedBook: I would populate a Laptech At-Cut 5.6448 MHz on the first area of the FiFoPi XO area for this frequency.

I also have few 24/88 & 192 materials from online libraries and then my choice could be a Laptech At-Cut 24.576 MHz dedicated for them for the second area of the FifoPi.

Am I ok with that choice? I want something simple without oven so my choice of At-Cuts XOs despite knowing OCXO Sc-Cuts are better.

Related to my XOs choice above I would like please to know if there is a big SQ difference between the Colpitts-Clapp board and the Pierce board. From Andrea Mori's posts I'm believing the Pierce oscillator could be a little better without being sure of that.

Has anybody tried to use 3 pins LTO3042 ldo regs for the 15V & 3.3V directly on the Colpitt oscillator board to reach a better PSRR & noise result versus the main TWMC main power board ? Could it gives a better result than the Pierce witch regs are farer of the board ?

I don't know if Ian's FiFoPi supports 5.6448 MHz with 24.576 MHz.

You could use the new TWTMC-P2, double Pierce oscillators on a single board, maybe battery powered.
It's born to accommodate 22.5792 Mhz and 24.576 MHz At-Cut crystals, but you can replace the first crystal with a 5.6448 MHz simply replacing a few components.
It will be available soon.
 

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Thank you, this is my understanding but the gap between the two frequency is unusual.

Halas I saw the DIL16 areas of the FiFoPi were flipped at 90° : so on the FiFoPi you can not use any more the the Andrea Mori's former oscillator boards stacked on the DIL adaptators. You can only use the DIL adaptators but wirered to the oscillator boards trough uf-l cables if you choose the FiFoPi. But you XOs will be very far from the DAC chip. So jitter added which is a pitty when choosing good XOs.

Now a Laptech should be at least better than a CHHD-957 directly stacked despite the extra length of wire needed for the Laptech oscillator boards with a FiFoPi. I saw IanCanada has 2" uf-6 cables...
 
I don't know if Ian's FiFoPi supports 5.6448 MHz with 24.576 MHz.

You could use the new TWTMC-P2, double Pierce oscillators on a single board, maybe battery powered.
It's born to accommodate 22.5792 Mhz and 24.576 MHz At-Cut crystals, but you can replace the first crystal with a 5.6448 MHz simply replacing a few components.
It will be available soon.

I have designed a similar clock board under the guidance of pulsar clock.

Screenshot_2017-10-31-23-15-23-446_com.google.android.gm (1).jpg
 
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