Can Audio library be extended to 32 bit?

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In my project, only 24 bit audio streaming to and from the codec are required, no processing of the audio samples are needed.
 
PaulStoffregen said:
This has been discussed numerous times!

Follow this thread for updates:

https://forum.pjrc.com/threads/27215-24-bit-audio-boards
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Thanks for your quick reply, Paul. I read through the thread you suggested. For the hardware, whollender's design is great: https://github.com/whollender/SuperAudioBoard. For the software in Teensy to support 24-bit, I only found nodae's experimental source: https://github.com/nodae/teensy_i2s_experimental, but it is RX part only, interrupt-based only. Is above information about the software the most updated regarding the 24-bit audio? Thanks for your time. :D
 
I will try this week. Paul, have you tried if the I2S clocks are provided by the audio codec? So that teensy only needs to feed and fetch data sample in response to the clocks.
 
chensx2012 said:
if the I2S clocks are provided by the audio codec?
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That's the slave mode objects. They're not very well tested, but at least worked at one point with one chip in one particular mode. I'm pretty sure that code has lots of bugs. If you fix any, please send a pull request on github!
 
Is this the latest on slave mode I2S?

I love the new 4-channel I2S modules and like to use them for multiway active speakers. Ideally the input is digital audio, but things like Bluetooth or USB->I2S modules need slave mode interfaces.
I found out that an I2SS input alone does not work, it's the I2SS output module that puts the external clocks to work. And there is no slave version of the quad output. So I'm doomed, right?

Even without quad output, I see the problem that slave mode requires 1.4112MHz bitclock, while my USB-DAC PCM2707 for example delivers 2.8MHz. Now the teensy confuses channels, as it simply counts to 32 for 2x16bits, instead of waiting for the other edge on LRclock to switch channels.
 
All the I2S slave mode stuff is pretty unstable right now. Sorry.

Even when slave mode is working well, it'll only ever support stereo. For quad channel, Teensy has to be the I2S master.
 
Understood.

The hardware solution would be inserting an asynchronous samplerate converter (SRC) chip to the I2S input.
On the software side, I found MickMad's project of a native USB audio interface. Could you tell us your latest thoughts on that?

USB audio is supported by both IOS and Android devices, so that would be the easiest way to stream bit-precise audio into the Teensy (although some SRC may still be needed).
 
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