How can we connect the CS8414 to the CXD1244

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#2
Unfortunately, I don't think these two ICs can work together. The problem is frame lengths; the CS8414 only wants to output a 64 bit frame, while the CXD1244 only wants to accept a 48 bit frame.

I don't think that there is any way to get around that incompatibility (at least not practically). Someone else may have a better idea, but I'd start thinking about using a different digital filter or receiver.
 
#4
It looks to me as though those are all the same; the frame length is 64 bits. I had a short look around, and none of the S/P DIF receivers I could find supported a 48 bit frame.

Is there any particular reason you want to use the CXD1244?
 
#5
Hello

I allready have this chip, and finding any other digital filter chip here arround are problematic.

And at first look it have better bits of precision in the intermediate calculations than SM5840's and SAA7220.

And the CXD1244 do have a ripple within .00001 db and attenuation at -100 db

The PMD100 would be better but to hard for me to implement and anaway I can't have it here arround.

How about reclocking after the digital filter for the right frame length ?

Thank

Bye

Gaetan
 
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#7
Hello

How about using one of those 2 circuit to convert 64 bit frame to 48 bit frame (I2S to Sony ( aka EIAJ )) ?

Thank

Bye

Gaetan
 

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#8
circuit to convert 64 bit frame to 48 bit frame
Click to expand...

But neither of those circuits do that. The main clue is the BCK line, on each of the above circuits it is only inverted twice, coming out more or less the same as it went in.

Frame length and BCK frequency are analogous. If you have data with a sample frequency (fs) of 44.1 kHz (which you do), and a BCK frequency of 64 x fs (which a CS8414, DIR9001, DIR1701 and DIR1703 all output) then the BCK will cycle 64 times per sample, clocking out 64 bits, hence a 64 bit frame.

So, for a 48 bit frame you'd want BCK to have a frequency of 48 x fs, a different frequency. If the BCK frequency hasn't changed, neither has the frame length.

That said, it is still possible to connect a S/P DIF receiver to this CXD1244. If you used a DIR9001, setting it to output 16 bit right justified data and a 384 x fs recovered master clock, deserialised the data it output, latched it, and reserialised it using a clock divided from the recovered master clock, you'd be away. This is something you'd want to use programmable logic for, and something with a fair few macrocells as well. This wouldn't be a trivial undertaking.
 
#9
Hello

I may not try that with the CXD1244.

Few months ago, I've try a non oversampling TDA1541A dac using a IV amp with 20khz low pass filter , but in orchestral music it was not very good.

There is also a better solution, it's a kind of shift-register 4X analog oversampling, here is the schematic, what do you think of it ?

Thank a lot for your help.

Bye

Gaetan
 

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#10
Looks quite cool, though you'd want to have a good supply of TDA1541As!

Sound wise, it's too hard to say whether something will sound any good just from looking at a schematic. The only thing I would watch is the CD4517, they're getting hard to find due to the prevalence of programmable logic, and it'll be running at its limit, so you'll need to get a good brand one.

Good luck with your DAC,
Anton
 
#11
Hello

I have six TDA1541A that I've buy in the 90's, original from Phillips.

I've try few kind of dac, but I still hesitate to try this analog oversampling, but with so much chip and the CD4517 it may have lot of jitter ?

Have you seen any errors in that 4X analog oversampling schematic ?

Thank

Bye

Gaetan
 
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#13
I second the above, that thread has some great stuff going on.

Mucking around with glue logic can be unpredictable. It may sound better than four TDA1541As in parallel, or it may not work at all, and I can't tell which from one very incomplete schematic.

I especially steer clear of those designs since I don't like to prototype. You've got to do a lot of prototyping o make stuff like that work well.
 
#14
gaetan8888 i answered you in a e-mail letter, but do not know whether it has come to you.
Hi Gaetan
1244 needs 384fs clock. He was designed for 48BCK but works even with 64BCK. You need sync reclock after DF. And be VERY carefully, OS DAC is much harder to build compared to simple NOS.
1244 works with 64BCK in my dac Overture v3.0

Regards, Nazar
 
#15
Nazar_lv said:
gaetan8888 i answered you in a e-mail letter, but do not know whether it has come to you.
Hi Gaetan
1244 needs 384fs clock. He was designed for 48BCK but works even with 64BCK. You need sync reclock after DF. And be VERY carefully, OS DAC is much harder to build compared to simple NOS.
1244 works with 64BCK in my dac Overture v3.0

Regards, Nazar
Click to expand...

Hello

I will look at my anti-spam section, sometime I can received one email and the other are stop by the anti-spam or sometime (but not often) Hotmail don't send the email I want to send. Sorry for that.

I've found a Adcom GCD-600 cd player for low cost and I mod it a bit, it sound better than my Denon DCM-420, but it still could be much better with more complex orchestral music. The CXD1244 would come from my Adcom GCD-600 cd player.

After trying few diy Dac I'm looking for better but can't find all types of digital filter or dac chip, so I allways work with the parts from my parts bin.

Complex orchestral music are the reason why I did not like non-oversampling Dac.

Btw I don't see the schematic of your dac Overture v3.0 in your web site.

Thank

Bye

Gaetan
 
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