
Home  Forums  Rules  Articles  The diyAudio Store  Gallery  Blogs  Register  Donations  FAQ  Calendar  Search  Today's Posts  Mark Forums Read  Search 
Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc. 

Please consider donating to help us continue to serve you.
Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving 

Thread Tools  Search this Thread 
25th April 2012, 06:30 PM  #1 
diyAudio Member

How to calculate fs bit clock knowing crystal frequency?
How to calculate fs bit clock knowing crystal frequency?

25th April 2012, 07:21 PM  #2 
diyAudio Member

According to the data sheet for the WM8741, the crystal frequency is fs.
fs/divide ratio (32, 64, 128, 256, etc) gives the data rate. eg. 24.576ZMHz clock /256(divide ratio) = 192KHz data rate. I suspect it is dependent on the DAC. What device are you using? 
25th April 2012, 08:17 PM  #3 
diyAudio Member

My device have a clock of 16.9344MHz, wich fs have?

25th April 2012, 09:16 PM  #4 
diyAudio Member
Join Date: Apr 2003
Location: Eastern Pennsylvania

The bitclock (BCLK) frequency can be calculated as follows below.
1. If the left and right channel data are in multiplexed serial format (such as they typically are before entering an oversampling interpolator) then: BLCK = original input sample rate (Fs) * the oversampling ratio * 64 bits per frame. 2. If the left and right channel data are in demultiplexed parallel format (such as they typically are after exiting an oversampling interpolator), then: BCLK = the original input sample rate (Fs) * the oversampling ratio * 32 bits per frame. For points in the DAC where oversampling has not been applied, the oversampling ratio in the above formulas = 1. Note: There also is a rarely utilized demultiplexed parallel 16 bits per frame I2S data format.
__________________
Ken Last edited by Ken Newton; 25th April 2012 at 09:29 PM. 
25th April 2012, 10:33 PM  #5 
diyAudio Member

Still don't know how to calculate?

27th April 2012, 04:57 PM  #6 
diyAudio Member

Anybody can help me?

27th April 2012, 05:04 PM  #7 
diyAudio Member

What is your crystal frequency?
What DAC or part are you using? What sample frequency (44.1K, 48K, etc)? 
27th April 2012, 05:08 PM  #8  
diyAudio Member

Quote:
DAC TP Buffalo III Transport CEC TL1 uses CD red book 44.1KHz Last edited by merlin el mago; 27th April 2012 at 05:16 PM. 

27th April 2012, 05:16 PM  #9 
diyAudio Moderator

How are you connecting the dac to the transport I2S (presumably) or spdif? I think you need to provide some information on the transport chip set as well.
__________________
"Extraordinary claims require extraordinary evidence."  Carl Sagan 
27th April 2012, 05:20 PM  #10 
diyAudio Member
Join Date: Oct 2004

It is implementation dependent. You could guess that it is 256fs
44.1x256=11.2896MHz 11.2896*3=33.8688MHz 33.8688MHz/2=16.9344MHz In this case the clock goes through some logic to be multiplied by 2 and then divided by 3 to arrive at 256fs. So it depends what kind of multiplication and division the clock goes through
__________________
www.hifiduino.wordpress.com 
Thread Tools  Search this Thread 


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
16AKSS7ET crystal frequency  xplod1236  Parts  1  8th December 2006 04:54 AM 
Marantz CD11 crystal frequency ?  joeling39  Digital Source  0  6th June 2006 10:42 AM 
low ppm crystal clock?m where  tone  Digital Source  6  27th February 2003 10:23 AM 
5.6448mhz clock (crystal)  glewis4744  Digital Source  1  16th January 2003 10:18 PM 
crystal frequency question  pjkunz  Digital Source  6  6th December 2001 02:31 PM 
New To Site?  Need Help? 