No way, no input of an audio system (any!!) would require such. WHAT would make sense is that there might be a massive impedance mismatch (this is OHMs) - but rather unlikely. COAX (SPDIF) out is on a 75Ohm impedance and needs at least 0.5Volts (but usually it is quite higher). So it could be that the PI2AES RCA (SPDIF) output is faulty!! The optical TOSLINK output seems to work though (personally I don’t like nor use it as it has massive jitter, which COAX SPDIF output does not have…
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Sure, that makes sense. I was under the impression that the Voltage/Ohms would be standardized across coax for audio.
The Digi Coax (SPDIF) does not work for me on both HATs
But digi coax converted from the toslink, and the BNC work. I don’t know what is going on to be honest.
I went into this HAT purchase with the intention to run coax and then i2.
Well, if TOSLINK works and SPDIF (COAX or BNC) does not, then this output is FAULTY on your PI2AES!!
And YES, the COAX/SPDIF output is indeed standardized! See S/PDIF - Wikipedia
Btw. how long is your cable from PI2AES to your speakers? Max 10 meters (30ft) is permitted!!
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Yea I think so too.
I just find it odd that I received 2 with faulty coax ports. I will report back to pi2AES and see what they say. Thanks for the info!
Don’t forget, the PI2AES is a NEW VERSION, so faults could happen based on that…
Both ports (BNC, RCA) are basically parallel, so I would guess the driver circuitry for them might be faulty!
Ask them for a TEST of the BNC/RCA SPDIF output before they even sent it out!!!
From the HAT outputs:
The toslink port is operational
The BNC port is operational
The digital coax port* is NOT operational
To clarify.
I have the device connected to the speakers by a 1 foot coax cable.
Yes, I am going to request another board that has been proven to be functional be sent out.
Edit: Added port*
I contacted Pi2AES and the rep says that he guarantees that the coax ports are functional, that there is no need to send me a replacement since they all work the same, and that I should send the HATs back for a refund.
Talk about above and beyond customer service.
You contradict yourself if you say “The BNC port is operational” and “The digital coax is NOT operational” - BNC out (aka SPDIF) IS DIGITAL COAX!!!
Guess I let you go here…
There are three outputs:
AES
Coax
BNC
… you can easily check it youself here
No I do not contradict myself. I am using the PI2AES version 2. There are 5 possible outputs.
The BNC SPDIF port is operational.
The toslink SPDIF port is operational.
The digital coax SPDIF port is not operational.
The i^2 port is not tested by me at this time.
The XLR port is not tested by me at this time.
Edit: Added i^2 and XLR test update
Here is the oscilloscope reading from the BNC port:
Here is the oscilloscope reading from the digital coax port:
From the wiki article, the min voltage required for S/PDIF is 0.2 V. The digital coax port on the PI2AES is reading an output voltage of 0.12 V. Well short of the 0.2 V min.
Update: Pi2AES refuses to acknowledge the results that indicate that the digi coax port is defective, avoid Pi2AES v2 HAT like the plague. Their customer service is akin to gaslighting. Not worth the hassle.
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That output on the right side is the digital SDIF AES3 output. That is certainly indeed way too low voltage!!
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Glad I found this post. I currently have one HiFiBerry Digi+ and was about to order a couple of the Pi2ES PROs… I think I’m gonna search for another option now. (preferably using I2S over HDMI)