What are my options with I2S as the output?

I’m looking at a DAC (Denafrips Pontus) that has I2S as an input and I’m trying to figure out a way to take advantage of that in Roon.

I’ve been searching around for this, but I’m still confused.
If I select the Audio Hat option as “Raspberry Pi DAC I2S” where is this signal output?
Is it the GPIO lines? If so is, do I need some kind of a HAT to get that output via a HMDI port?


Something like the PI2AES hat, maybe? http://www.pi2design.com/pi2aes.html (Note: I’ve not personally used this product, only aware of it.)

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As I2S is intended as in internal bus for audio data, basically all HAT’s use I2S. The ‘Rasbberry PI DAC i2S’ enables the default overlay which works with most HAT’s.

What you’re looking for is a way to provide the I2S externally (like on a HDMI connector) to be able to connect an external DAC. In most cases this means that the I2S is made differential, because the I2S signal itself is not designed for long(er) connections.

So, as @cwichura pointed out, the Pi2AES device might be an option.

i2s over HDMI has a few options. Sonore, PS Audio, and Wyred4Sound all have various equipment that use that. I have two i2s streamer rigs which are Roon compatible: Two sets of Sonore microrendu>Sonore Ultradigital. One feeds a W4S DAC, the other feeds a PS Audio Stellar Gain Cell Preamp/DAC. TBH, current USB tends to be pretty close performance wise IMO. Five years ago it wasn’t, but USB has gotten much better. I’m sure i2s is stiil better on paper, but I try not to worry about stuff I can’t hear.

Thanks for the suggestions and explanations. :+1:

Plenty of DACs have i2S input these days. Denafrips, Rockna, PS Audio, etc. Even Topping’s D90 well under $1K.

This device is one of relatively few devices with the i2S over HDMI output.
You can add the OS of your choice including Ropieee.

I am using the DDC converting USB to i2S/SPDIF/AES output. It is not only converting but do USB isolation/femto clock - signal re-clocking and regeneration.

I have owned Singxer SU1, SU6, Gustard U16+C16, now I just keep the Audio-GD DI-20HE.

I’ve read the Pi is limited to DSD64 or 192 kHz for PCM when using a HAT for I2S output like Pi2AES. Does anyone know why that is? Seems like that would be a step down from USB…

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It is a limitation of the chip used on the HATs in question.

Do you know of a HAT that will output I2S at DSD256 or DSD512? That’s ideally what I’m looking for. Thanks!

Hi, has anyone tried the Ian Canada FIFOPI Q2 ULTIMATE Reclocker Module from audiophonics.fr?

That’s a very interesting device there. It would be nice if someone like Hans Beekhuyzen would do a review of it.


I am very successfully using a Matrix X-SPDIF 2 interface, a usb format converter. USB in, with femto reclocking and format conversion to I2S on HDMI output (also outputs toslink optical, coax, and AES/ EBU simultaneously.) Output up to 32 bit / 768kHz, DSD 512, price $379.

Been using a Matrix X-SPDIF 2 for a few years as well. works perfectly and never had any problems with it.