Any project with PCM1704

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Doing a bit of cleaning I found an old gem: (sorry for the blurry pic)

692819d1532104258-project-pcm1704-pcm1704k-jpg

3xPCM1704, bought years and years ago for a project that never happened...


Anyone has an idea what they could be used for nowadays ?


or if anyone can demonstrate they have the skill to use them I'll send them away for free.
**Edit: I'll keep them for the time beeing**

Answers in the thread please.

@Mods, maybe should have posted in swap ? It's not like I want any payment other than getting
these chips to play music - like they were meant to ;)
 

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Genuine PCM1704 is 80 USD each at Rochester Electronics (well-known authorised EOL IC dealer).
And that is not even K grade.
Rochester Electronics
: Part PCM1704U-J


So I suggest you post them at Swap Meet for at least 80€ each.
If someone would pay that (fair) price, he has some serious use for them.
You cannot drive them directly with I2S, but need glue logic or a digital filter chip like PMD100.

We have plans for them (we bought a bunch before they got obsolete), but no time yet to execute.
Or maybe you should keep them and do something with them afterall.
You won't find such nice sounding DAC anymore these days because they are just too expensive to make.
And 24/96 is more than enough for playing 16/44.1, unless you want to play 24/192 material, or above.


Patrick
 
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Joined 2007
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Hi ... Just FYI the PCM1704 is likely capable of going up to 768 kHz/24 bits or there's a rumour that it will even do 1.536 MHz. This is with no oversampling.

If you decide to use the 1704 for a project - and maybe prefer a simple(r) setup - JLsounds USB-to-I2S directly offers the bit "shuffling" needed to align two channels so that external oversampling filters or electronic circuitry for this is not needed.

I2SoverUSB - I2S over USB Audio

Otherwise no affiliation with JLsounds ;-) ... And I otherwise have no experience with how this "USB" bridge sounds.

Cheers,

Jesper
 
Got an Email back from the HKshop:

"This is a product for diyer to enjoy. It has limitless possibility." - emphasis mine.
"The store item description contains all the usage information and manual." - well, it doesn't.


With limitless possibility, I'll better stay away - I'm a sedate kind of guy...

Seems the 768khz module can only do 384khz, pity - original filter does 768k/channel (?)

Probably means the reference implementation of the output filter is off too.


I think I'll order the DAC board and take a look at it.

And the JLsounds converter looks a bit more universal...and cheaper :blush:
 
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I'm confused, why are you posting a 'propaganda'picture of a AD1865 ?

...it's not even made by the same company :confused:

Thanks for your reply. Sorry for any confusion in my brief post. Maybe I can try and make it a bit clearer.

As I wrote above, I dont know much and Im interested in building an R2R DIYINK DAC. So Im asking for advice about the sound of the DAC in general and the R2R DIYINHK "stop clocking" scheme in particular. There are some really great and helpful experts on this site. So is the stop clock thing a good idea or propaganda?

From the PCM1704 page
"The I2S reclock input circuit in this PCB is based on the Analog Device AN207 stop clock algorithm " and the image is from the DIYINHK site showing the stop clock idea for the AN1865, but I think its the same idea with the clock turned off after the data is latched in, so during the analogue output there's less digital noise? I've probably got that all wrong. :eek:
 
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