BBB + I2S + DAC

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There are many threads that are talking about this subject, but are a little confusing.

So my question. What DAC do you recommend for BBB that connect to I2S? And what external cards are needed (clock,...)? This is not to include the cheapest parts from Ebay, but to build the system with audiophile quality at normal price range.
 
I recommend it to people looking for an 'analog' kind of sound as it delivers listening satisfaction in bucketfuls. I used TDA1543 its fine but not as transparent nor as low power as TDA1387 - I no longer design with TDA1543. If you don't use an LC filter after the DAC then probably TDA1543 sounds better - with the filter TDA1387 easily trounces the higher power chip. I take it the reason that ecdesigns prefers TDA1543 is that he hasn't found a passive filter that he likes.
 
Good question - I've never tried it but I'd guess yes it would. All DACs generate out of band noise and an LC filter is a very effective way of killing that without introducing other audible artifacts (unlike active filters which are the usual choice for filtering S-D DACs).
 
I like lots of questions - helps me to be more sure I haven't overlooked something important :)

My original filters (this is going back a couple of years now) were built from handwound inductors. They were wound on pot-cores. Then I found some much smaller inductors with enough Q (the TDK 7mm ones). Those TDK inductors are limited to 1mH for the max value, so need rather a lot of gain later to get back to normal DAC output levels.

If you have enough patience, you could wind air-cored inductors if you can't get hold of pot cores. However you'll need a lot (maybe of the order of 1000) turns to get high enough Q and inductance. Just for an example I've been winding trafos and before I put the coil into the core I checked its air-cored inductance. With 1230 turns I got an inductance of 31mH on a bobbin of 22.5mm diameter, 17mm high. Since it was for a trafo primary this winding only uses half the available space on the bobbin. It was wound with 0.21mm wire. The 20kHz Q measures 63, considerably better than the TDK 7mm inductors, so this air-cored coil will work well as part of a filter provided its put in a shielded box to protect it from hum.

Of course the downside of air-cored inductors, apart from needing to be shielded, is the time it takes to wind them. But it can be considered a form of meditation....
 
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