R-2R DIY DAC on a budget(ish)

[robush4]

Hello diyaudio.com! This is my first post, but I wanted to comment how much I have enjoyed reading threads here for the last month or so.

Anyways, I am looking to make an R-2R DAC on the cheap. I have read most of the threads about Soekris’ dam1021 (http://www.diyaudio.com/forums/vend...crete-r-2r-sign-magnitude-24-bit-384-khz.html), but i think a full build of that would be out of my price range of ~$300 (mainly due to the cost of the linear power supply). Also, it seems the 'Red Baron' dac has been discontinued. I would really like to find a diy dac that uses the PCM1704 or similar chip. I have searched around, and finally decided to just start a thread.

If i cannot find anything that matches my budget in the r-2r realm, i will probably just go with a modi 2 uber.

 

[abraxalito]

PCM1704 is hardly a 'budget' chip - Mouser still has a few in stock at a price over $80 each. Once those are gone though it looks like there'll be no more as they're 'EoL'. Since they're mono you'll need two chips. If you're looking for that 'analogy' sound that's characteristic of R2R type DACs, may I suggest TDA1387? They're cheap as chips and much easier to implement. Only 16bits though. If you need more than 16bits there's always PCM1702 which while not in production tends to be available on the secondary market at a considerably lower price than PCM1704 and potentially sounds better.

 

[robush4]

PCM1704 is hardly a 'budget' chip - Mouser still has a few in stock at a price over $80 each. Once those are gone though it looks like there'll be no more as they're 'EoL'.

That is my reason for wanting to move quickly. Also, i should clarify that by 'budget', i mean around $300 for the whole thing. I could buy a couple of those chips and hopefully stay under the price ceiling.

If you're looking for that 'analogy' sound that's characteristic of R2R type DACs, may I suggest TDA1387?

thanks. found some interesting reading.

anyone know of a diy dac that uses the PCM1702 chip?

 

[abraxalito]

I agree its possible to get within your budget and still blow over half of it on the DAC chips, but why not undershoot the budget by a bigger margin and have some money left over for music? PCM1704 strikes me as poor bang-for-the-buck in terms of DACs when SQ is the desired attribute. Also if its your first DIY DAC you'd be well advised to get a couple of spares to avoid a fair amount of frustration down the pipe if you accidently slip when probing a pin.

Aliexpress has a good value looking DAC board available which nicely undershoots your budget (but you'll need a trafo):
XA3 Kit hifi DAC decoder with 4 pcs PCM1702 board-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group