Using a CD player as a DAC/analog stage for my computer?
Jan 29, 2005 at 4:16 AM Thread Starter Post #1 of 3

Zemo

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Would it be possible to use the digital outs of my emu 0404, and run it into the DAC stage of my njoe tjoeb 4000? The digital from the card would replace the digital comming from the transport...how hard would this be to do? The card can do coax, but the cable comming from the transport is like...7 conductors.

Ideas?

-Z
 
Jan 29, 2005 at 5:05 AM Post #2 of 3
Hopefully, there are quite a lot of details here : http://www.hifi-planet.com/ahnjoetjoeb4000home-en.htm Doesn't look that easy but should be possible. If I read those pages correctly, they implemented a very basic TDA1545 in there, just like the original cdp was.

First you would need to add a digital receiver to transform the spdif into the format taken by the TDA1545a (EIAJ 16bits). Something like the CS8412 would be easy to work with. CS8414 is easier to find but is smt.

Then, you have to tap the I2S lines and install three digital switches to pick between the flow coming from the transport and from the cs8412 add on card.

And of course, you must tap a power supply somewhere to feed those add-on.

Btw, is an upsampler installed in your tjoeb ? If not, it looks like they didn't touch the transport card (at least, they don't brag about it), which means the tjoeb 4000 is oversampling 4X. Sadly, the oversampling is done by the chip outputting the EIAJ, and rather poorly. This page could give you an interesting idea : http://www.ifrance.com/robinetron/cd...ck/hack_e.html If you're able to mod your player, you should understand those pages. The cd723 described is nothing but the cd4000. Internals are the same, only the package changes.

Those are rather heavy mods. Is your Tjoeb really that much better than your soundcard ? We had one of those cdp here and compared it to my lightly tweaked CD753, I wasn't really convinced.
 
Jan 29, 2005 at 5:36 AM Post #3 of 3
yup, I've got the upsampler. I looked over those pages you linked too, and the stuff on the second is way above my head at this point! I think I'll stick with it how it is!

As far as if it's better than my soundcard...I have yet to see. Yes, I have both of them here, side by side, but I can't do any proper testing right now. No real headphones or amp right now, and this room is a HUGE limiting factor for my speakers. I can't expect much from them until I get them in a good room.

Thanks for the tips!

-Z
 

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