TOPIC:

If you can solder, you can put 4 I2S to SPDIF board connected to the I2S out of the nanoavr. I did put 3 curyman dac (i'm in 5.1 with an analog pre-amp) to go analog on mine and it's working perfectly, way better than the included HDA analog board. For the pin out have a look at the minishark pinout it's the same. Cheers

Cool!

I went the root canal route of HDMI to SDI and then a 4 wide (8 channel) AES/EBU deembedder into an 8 chanmel Lucid DAC.

thegoodspot wrote:

If you can solder, you can put 4 I2S to SPDIF board connected to the I2S out of the nanoavr. I did put 3 curyman dac (i'm in 5.1 with an analog pre-amp) to go analog on mine and it's working perfectly, way better than the included HDA analog board. For the pin out have a look at the minishark pinout it's the same. Cheers

Hey, look, headers!... (don't know why I never took this thing apart, I take everything apart...)

Thanks for the info, couldn't wait to get home to look!

I have a few questions if you don't mind...
Any idea if they are active on the HD version? I'm guessing the HDA is the same only with a miniDAC8 on its back.
I'm assuming you removed the daughter board and have the DACs going straight off the main board?
Any idea the sample rate, I'm guessing 96k...
The two jumpers on the board, are they jumped on yours too? (hopeful thinking that maybe removing ones would enable outputs if not active)

I'd asked miniDSP years ago about daisy chaining nanoAVR ("won't work", but it does!) or if they had a way to extract 4x pairs of digital audio from HDMI ("no"), too bad I didn't know about the headers... :\

This weekend I'll pull out my scope and poke around...

Thanks again!

(images of internals removed, locations as viewed with connectors facing yourself; there's 2x 30-pin female headers who's offset looks similar to the miniDAC8, a 14-pin male (top left of right 30-pin), 4-pin male (bottom right of left 30-pin) and 5-pin male (ISP for main chip? top of left 30-pin) headers that doesn't match miniDAC8's footprint, 2x jumped jumpers near the left 30-pin, an additional 5-pin (ISP) on other side of board by a PIC and a 4-pin male connector by power)

rhollan wrote:

Cool!

I went the root canal route of HDMI to SDI and then a 4 wide (8 channel) AES/EBU deembedder into an 8 chanmel Lucid DAC.

Which de-embedder did you go with?

AJA 3G-AM. I got it for about half the $795 MSRP.

I think the sarcasm is unwarranted, perhaps go back and read the second post in this thread.

True they coud't tell you, that is breaking the HDMI licencing copyright...
I suppose the HD is identical to HDA i just removed the 8ch dac on top and move the nanoAVR board out from the box.
Send you some pict when i can.
Sample rate is 96K internally so i suppose it's 96K on the output as well (don't know i'm doing I2S to analog straight away)
Bare in mind I don't use the Mclock because the Curyman DAC doesn't need it.

The headers are active on the HD ( & DL)!

The 30-pin header nearest the center is the miniSHARC J2 equivalent one, pin 1 is closest to the power plug. The I2S pairs light up whenever the source has those channels, all pins are 3.3v signal and sample rate is 96kHz. There is 5v power available on the white connector near the power plug, what appears to be 2x ground on the centermost side, 2x 5v on the outside straight off the power plug.

(edit: one important difference from miniSHARC J2, MCLK is on pin 11 not pin 9)

Looking for I2S to S/PDIF converters/transmitters, I found the HiFiBerry Digi+ (wolfson WM8804 IC), although while it just works with Raspberry Pi, looks like it will require an Arduino to initialize and configure it over I2C for stand alone. I've figured out most of what is needed to enable and configure by looking at RPi driver source, but I feel like I'm studying in collage again trying to decipher the PLL parameter calculations/code :cry:
The Pro version with the additional oscillators simplifies the results of the calculations though to the point I can take a few guesses and hit the right config for 96k...
The IC has a hardware only mode too, but I'd need to re-read the datasheet in more detail, design/make pcb, order/solder smd components, etc... I think a few pre-made ones, Arduino and code might be easier/quicker...

Will look a bit more for converters, then probably order a Digi to play with...

Thanks the miniSHARC info and the spark thegoodspot

If you get MClock out maybe this is a simplier board,
www.audiophonics.fr/en/diy-interfaces/i2...-dsd128-p-13627.html

I might order it to try to use my spare 7-8 Out i don't use to make an even better Left/Right Output from NanoAVR to External Hi End DAC
Glad that did help you, that what forums are for
Cheers

I had ordered one of these from eBay/China (received version V5.1):
www.audiophonics.fr/en/diy-interfaces/di...-wm8804-p-12561.html



but I'm not seeing any output on it's signal or S/PDIF pins ('A', 'B' & 'C'). In trying to determine if it's bad of if one with an onboard MCLK is required, I wanted to verify the comms between them. I verified output on nanoAVR's LRCK, BCK, & Data pins but MCLK is more than my scope's bandwidth allows me to see.

I'd appreciate it If anyone following this discussion would be able to check if the nanoAVR's MCLK has an output... (24.576MHz on J2:9 - when viewed from rear, right 30-pin header, right side, 5th pin from rear is MCLK, 4th pin from rear is GND)

(edit: bought a decent scope, all necessary output pins are active, MCLK is on J2:11 not J2:9 like miniSHARC, frequency is 24.576MHz)

I do have an easy Solution for you.
Just buy a Meridian HD621 works fine for me, they are not too expensive these days.

jan.p.ho wrote:

I do have an easy Solution for you.
Just buy a Meridian HD621 works fine for me, they are not too expensive these days.

The digital audio out is encrypted in a proprietary Meridian format and only compatible with Meridian products.

That’s what they tell you.
I can tell you, that I’m using a Dolby cp650 with it via 4 stereo channels over 4 aes


Well there is one thing. You can’t go higher than 48khz. Above that it is encrypted.

jan.p.ho wrote:

That’s what they tell you.
I can tell you, that I’m using a Dolby cp650 with it via 4 stereo channels over 4 aes


Well there is one thing. You can’t go higher than 48khz. Above that it is encrypted.

Now that IS interesting. I have been going through an HDMI to SDI converter that drops HDCP and then SDI deembedders, after a pair of nanoAVR (BM and DL) to get AES/EBU audio. Strictly 48 kHz as that is all SDI supports (well you can do 96 kHz but it is non-standard). But the Meridian only sports SPDIF on coax, so one would need level shifters to AES levels, no?

Nope this “mmhr” output is a standard 8ch AES over cat6 cable.