This is an interesting thread 🙂 I have three audio extractors from Aliexpress which I just cracked open:
From left to right:
Pin 37 - 40 indicate I2S output which is routed to the MS7124 DAC on all three boards. I assume those boards could be repurposed for a cheap quick and dirty solution if you manage to break out the signals without EMC issues.
Now you might wonder why I have three of these boards laying around in the first place. The reason is simple, I all bought them one after the other and none of them really work. The first one only outputs audio when U turn it on before I turn on my projector, which is cumbersome because I have a central mains switch and the other two only let my source (PC) output 1920x1080i interlaced video.
I cannot find any more documentation on the IC, I would really like some I2C register documentation, because these seem to be configured incorrectly. The first one shows up in windows with the correct display EDIDs and the name of my projector which is great, the 2nd and 3rd one shows up with MS-HDMI-RTX, so these are easy to identify in case you don't want to crack them open.
So completely unrelated, I am actually interested which converters you have with the EP92A3E ICs. Can you post some links to buying them? I am this close to pulling the trigger on 10 different HDMI audio extractors which I already have in my Amazon basket and testing them before returning the 9 I don't like....
Cheers, Andre
From left to right:
- https://www.aliexpress.com/item/1005004614491741.html
- https://www.aliexpress.com/item/1005001497299425.html
- https://www.aliexpress.com/item/1005004750956100.html
Pin 37 - 40 indicate I2S output which is routed to the MS7124 DAC on all three boards. I assume those boards could be repurposed for a cheap quick and dirty solution if you manage to break out the signals without EMC issues.
Now you might wonder why I have three of these boards laying around in the first place. The reason is simple, I all bought them one after the other and none of them really work. The first one only outputs audio when U turn it on before I turn on my projector, which is cumbersome because I have a central mains switch and the other two only let my source (PC) output 1920x1080i interlaced video.
I cannot find any more documentation on the IC, I would really like some I2C register documentation, because these seem to be configured incorrectly. The first one shows up in windows with the correct display EDIDs and the name of my projector which is great, the 2nd and 3rd one shows up with MS-HDMI-RTX, so these are easy to identify in case you don't want to crack them open.
So completely unrelated, I am actually interested which converters you have with the EP92A3E ICs. Can you post some links to buying them? I am this close to pulling the trigger on 10 different HDMI audio extractors which I already have in my Amazon basket and testing them before returning the 9 I don't like....
Cheers, Andre
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Thanks for posting the details. I wasn't able to get one of those on short notice so I spend a little more money than necessary and picked up a Lindy HDMI 4K60 Audio Extractor from a local store ... just to learn that at first, it also did not show up as an audio device in Windows 10.
Then I got really suspicious and recabled everything in exactly the same way and power-cycled all devices and ... it worked. Maybe it was a loose connection, or power cycling did a reset on some devices' EDID cache but in the end, the following two devices performed well for me:
In any case, I immediately took the Lindy box apart and discovered yet another Chinese IC: a GSCOOLINK GSV2001. I searched for a while and could find no information whatsoever, not even a simple pinout, but here is a shot of the internals:
The MS4344 next to the Chinch out is yet another ADC that accepts I2S; you can clearly see the traces. THE ??32F103 is an Arm M3 Microcontroller from another Chine manufacturer. This device is firmware upgradeable via USB, but I couldn't find any firmware on the Lindy homepage, so maybe they added that as a precaution. This is probably what makes this thing so expensive.
Cheers, André
Then I got really suspicious and recabled everything in exactly the same way and power-cycled all devices and ... it worked. Maybe it was a loose connection, or power cycling did a reset on some devices' EDID cache but in the end, the following two devices performed well for me:
- Lindy 18G 38361 HDMI 4K60 Audio Extractor (https://www.lindy-international.com/HDMI-4K60-Audio-Extractor.htm)
- HDMI Audio extractor 4K60Hz YUV 4:2:0 (third one in my post above)(https://www.aliexpress.com/item/1005004750956100.html)
In any case, I immediately took the Lindy box apart and discovered yet another Chinese IC: a GSCOOLINK GSV2001. I searched for a while and could find no information whatsoever, not even a simple pinout, but here is a shot of the internals:
The MS4344 next to the Chinch out is yet another ADC that accepts I2S; you can clearly see the traces. THE ??32F103 is an Arm M3 Microcontroller from another Chine manufacturer. This device is firmware upgradeable via USB, but I couldn't find any firmware on the Lindy homepage, so maybe they added that as a precaution. This is probably what makes this thing so expensive.
Cheers, André
Hi, very interested in your results.
I have the item you call option 2, the extractor with the blue stripe, on its way to me. If I understand your posts correctly, you needed to do a firmware upgrade to get it to work properly?
I also bought an HDMI splitter. It has a MS9332 chip in it. I was hoping it could also be turned to an extractor, but I cannot find a pinout for it anywhere.
I have the item you call option 2, the extractor with the blue stripe, on its way to me. If I understand your posts correctly, you needed to do a firmware upgrade to get it to work properly?
I also bought an HDMI splitter. It has a MS9332 chip in it. I was hoping it could also be turned to an extractor, but I cannot find a pinout for it anywhere.
Apart from the Lindy one, the other devices do not really have a way to update the firmware by the user. All three devices from my first post worked differently in my setup, that's why I suspected the factory configuration of the IC to be differents. If there would be any actual datasheet or application note for the IC, we could at least talk to the chip via the I2C bus and change the configuration to see if it fixes anything. But without proper documentation, no way. AFAIK you can't just get the chip to spill it's secretes over I2C without knowing what to probe for. And that information would be in an actual datasheet which is likely under an NDA given the scarcity of publicly available information.
But a sample size of one is no statistic ... So maybe your device performs well in your setup 🙂 Let us know!
But a sample size of one is no statistic ... So maybe your device performs well in your setup 🙂 Let us know!
I have a (kind of) related question: Does anyone out there know if it's possible to get a signal from any of the chips in these HDMI Audio Extractors which changes state when the HDMI input goes active? I want to switch on an audio power amp when the video is present and off when the video goes away?
I've got one of the tiny extractor boxes which contains the MS9331, MS7124 and MS8005 chips
Thanks in advance,
I've got one of the tiny extractor boxes which contains the MS9331, MS7124 and MS8005 chips
Thanks in advance,
Just some info here regarding HDMI audio, that is true video HDMI output, not these bespoke I2S over an HDMI cable. Per the HDCP copy prevention standard, any extraction of the audio stream to analog must limit the output to 16bit 48K. That would also apply to SPDIF. This was done to deter copying of higher quality audio streams. So if HDCP is enabled on the content, this audio restriction must be applied per the licensing rules.
Now, the master key for HDCP has been broken and published for years. So it's possible these off shore low cost adapters are reporting back as a certified HDMI sink device and therefore may put that audio out in the native content format. But we really don't know without some extensive testing.
Now, the master key for HDCP has been broken and published for years. So it's possible these off shore low cost adapters are reporting back as a certified HDMI sink device and therefore may put that audio out in the native content format. But we really don't know without some extensive testing.
This is an interesting one...Site says for RPi but implies will work stand-alone. Unfortunately upon contacting them they say unavailable due to manufacturer problem sourcing of components.
https://quartzacoustic.com/shop/ras...gurable-inputs-and-outputs-with-oled-display/
HDMI/ i2s/ SPDIF/ in-out seems an all purpose device. If only it were available to test.
https://quartzacoustic.com/shop/ras...gurable-inputs-and-outputs-with-oled-display/
HDMI/ i2s/ SPDIF/ in-out seems an all purpose device. If only it were available to test.
I don't think there is a true HDMI input on this board DRONE7. Only PCM or DSD output from this HDMI connector.
Correct but included for interests sake.
Maybe this one...which I have and just tried. Could not get it to de-embed without an attached screen (contrary to their advice) however, with an HDMI-4K dummy plug all worked.
Max 16 Bit @192kHz.
Raspberry Pi Zero 2W running latest MoOde Audio and using SOX to resample.
Tested the 3.5mm output and tomorrow will try the Coax out (fingers crossed for higher bitrate)
https://www.blustream.co.uk/hd11au
Maybe this one...which I have and just tried. Could not get it to de-embed without an attached screen (contrary to their advice) however, with an HDMI-4K dummy plug all worked.
Max 16 Bit @192kHz.
Raspberry Pi Zero 2W running latest MoOde Audio and using SOX to resample.
Tested the 3.5mm output and tomorrow will try the Coax out (fingers crossed for higher bitrate)
https://www.blustream.co.uk/hd11au
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hello,
Has anyone managed to get multichannel i2s (seems to have 4x stereo pairs) with this one? I understood some of you were about to try it.
thanks.
thanks!
do you have the version of the board with the output i2s over HDMI socket soldered or the one with only the header?
(left or right below):
do you have the version of the board with the output i2s over HDMI socket soldered or the one with only the header?
(left or right below):
btw, to OP, i guess (and hope) it is not relevant anymore, but just in case, i believe the i2s pins on the amazon basics extractor are:
Yes, I found the schematic in the service manual of a soundbar with detailed pinout. Also have a modded hdmi extractor based on the same chip as multichannel spdif output for a raspberry pi. What I don't have is a datasheet.Let me know if you are interested.
Yes, I'd love to see it if you can send it. I really want to add some PCB to get at the raw 8 channel I2S if I can. I'm using a Dolby Decoder IC, but it's a bit dated and the HDMI approach seems a lot more flexible. I have some datasheets around for various ones, so if I can send you anything I'll try to. But drop me a DM if you can send me anything, thank you!