Modifying a TDA1549-based CDP to act as a DAC

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Yes I have no idea what I'm doing when it comes to this sort of stuff I admit it :eek:

I reckon, given your state of EE knowledge you'd be much better off with a complete DAC system on a board like this one : TDA1315H TDA1305T Decoders Fiber Coaxial to Analogaudio Signal DAC J164 80 | eBay

The TDA1305 has essentially the same back-end for D/A conversion as the TDA1549 so sound quality should be quite similar. You could always modify this PCB with the parts out of your Marantz if you feel so inclined :D
 
If i had any kind of knowledge relative to this stuff i would had gladly shared it, but as statted in my first post it's way over my head.

I may have been wrong proposing something that would have probably failed to work and i'm sorry for it but i tried to help as i could.

I'm glad that you have invested efforts to help and showed hints to make it work.

It's way more enjoyable and constructive that mock others interventions without adding much helpful informations.

A forum should be a place to share everyone knowledge indiscriminately of the level not a battleground.

I'm sorry again to have added fuel to the flames i really wish that BucketInABucket will find a way to make it work with your helpful advices.
 
I reckon, given your state of EE knowledge you'd be much better off with a complete DAC system on a board like this one : TDA1315H TDA1305T Decoders Fiber Coaxial to Analogaudio Signal DAC J164 80 | eBay

The TDA1305 has essentially the same back-end for D/A conversion as the TDA1549 so sound quality should be quite similar. You could always modify this PCB with the parts out of your Marantz if you feel so inclined :D
I do want to learn more; it's why I challenged myself with this. It might be stupid but at least the journey will be worth it even if it fails so I prefer not to go that option if possible :)

If i had any kind of knowledge relative to this stuff i would had gladly shared it, but as statted in my first post it's way over my head.

I may have been wrong proposing something that would have probably failed to work and i'm sorry for it but i tried to help as i could.

I'm glad that you have invested efforts to help and showed hints to make it work.

It's way more enjoyable and constructive that mock others interventions without adding much helpful informations.

A forum should be a place to share everyone knowledge indiscriminately of the level not a battleground.

I'm sorry again to have added fuel to the flames i really wish that BucketInABucket will find a way to make it work with your helpful advices.
No worries. Quite hard to get a little heated and thanks for trying to help!
 
I do want to learn more; it's why I challenged myself with this.

There's still more learning involved even with a ready-made solution. For example you'll need to figure out how to power it, how to get the S/PDIF signal from the outside onto the board without corrupting it, how to hook the audio outputs back to the CD player's circuits.

So any news from reading of the service manual yet? Hifiengine's blocked here so I can't help you with that.
 
From a quick scan of the DS, there's no way to use the upsampling filter other than by providing raw data off a disk. So if you want to continue with the plan of using the TDA1549 you'll need to add in an additional 4X oversampling filter after your S/PDIF receiver. There aren't too many choices of those (most stand-alone digital filters are 8X oversampling) - SAA7220 is one but I'd not recommend that as its power hungry and electrically noisy.
 
My XMOS idea is looking even better. You can get the XMOS HPA evaluation board, XK-USB-AUDIO-HPA, which is ready-made and includes the complete XMOS development environment. You can use the HPA, as supplied, as a USB connected DAC with headphone amp, and later adapt and modify it to suite your needs.

Connect BCK, LRCK, and DATA from the HPA to the TDA1549. Edit the supplied firmware to get the desired data format. Compile and download to the HPA. Use the music player on your PC to resample to 4Fs, as needed. Hit PLAY and enjoy the music.

If the $200 XMOS board is beyond your budget, consider the Cypress FX3. It is only $50 and supports USB 3.0. I am using the FX3 in my current DAC project.
 
From what I can see, the TDA1549 accepts data from the SAA7372 CD decoder. Datasheet here:

https://www.digchip.com/datasheets/download_datasheet.php?id=850988&part-number=SAA7372

Also, I have experience implementing basic power supplies, internal wiring and S/PDIF data transmission from when I played around with the Soekris DAM1021.

The TDA1549T is one of a small number of devices where BCLK must be based on 48Fs whereas just about every DIR since the YM3623 assumes 64Fs as a default.
 
Also, I've got one of these coming. Would reprogramming it do the trick if it was possible?

NO!!! That device is "locked" and can't be reprogrammed without special tools. You'd also need the source code for the firmware and the device driver. I doubt DIYINHK will provide them. Even if you could get all the above, it wouldn't work because the oscillators are the wrong frequency for the 48bit sample frame.

On the other hand, the XMOS development kit has everything you need to do the job, correctly, the first time. You also have access to many tutorials, demos, and the XMOS engineering staff. I've heard their customer support is outstanding.
 
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