Amanero Isolator/Reclocker GB

[acko]

Originally Posted by acko
Feedback from others indicate BBB (and other similar transports) with native re-clocking sounding better than RPi

Hi Acko. I wasn't making a judgement on which sounds better, just answering his question about i2s in the newer banana pi. The original one didn't have an easy way to get to the i2s signals.

No problems, understood
I was trying to cherry-pick from the lot

 

[DQ828]

That is 2.5in Spin SATA HDD into BPi.

Have I got this right, the music goes from the HDD to the RPi then to the BBB & finally to the DAC?

 

[Chanh]

Yap! You've got it right. Which is why I thought with the Banana Pro i2s direct, would eliminate a layer or two?


Sent from my iPhone using Tapatalk

 

[acko]

...I thought with the Banana Pro i2s direct, would eliminate a layer or two?

Good point Chanh! Why not try those leads as indicated by Palmito and compare with your current BBB setup

 

[nautibuoy]

Excellent! Can this JRiver stream native DSD like AssetUPnP? Re: post by Ray on his new setup

Acko, Asset UPnP has a RPi release (as well as a generic Debian one);

https://www.dbpoweramp.com/asset-upnp-dlna.htm

Only the V5 beta release can handle DSD though and that is only available on Windows currently. I asked and was told that a QNAP release (which I would guess will be Linux based so similar to the RPi release) is two months away.

 

[nautibuoy]

Yap! You've got it right. Which is why I thought with the Banana Pro i2s direct, would eliminate a layer or two?

Less is sometimes less, you would compromise the clocking arrangements compared with the BBB/SO3? Also, the eliminated layers are in the digital domain - now there's a debate and a half!

 

[acko]

Acko, Asset UPnP has a RPi release (as well as a generic Debian one);

https://www.dbpoweramp.com/asset-upnp-dlna.htm

Only the V5 beta release can handle DSD though and that is only available on Windows currently. I asked and was told that a QNAP release (which I would guess will be Linux based so similar to the RPi release) is two months away.

Thanks Ray, very exciting!

 

[nautibuoy]

@lintweaker
I have added an isolated I2C port to make it easier for your.
This is mapped to I2C channel#2 (I2C2_SCL and I2C_SDA) of the BBB.
You can now code away your control software for the AKM4490 DAC

An externally hosted image should be here but it was not working when we last tested it.

Acko, have you tried this with 90deg. header pins so that it stacks onto the BBB P9 header vertically; looks like just a little surgery needed in the bottom left corner. I ask because in a horizontal arrangement the outputs will be further away from my SO3 board and I want to keep all connections as short as possible.

Anyway, I'm as keen as mustard to get my hands on one....

Is the current GB list for these boards or the Supercape. You've muddied the waters with your little surprise.

Ray

 

[stijn001]

Yes, this is in the works already - UFL connections from S03 to DAM1021 DAC

I'm expecting to recieve the R-2R dac in the post on monday.

The dac already has an isolator and reclocking. Would it not be detrimental to put two isolators/reclockers in series? Synchronised clocking with the BBB, would still be an advantage.

I've heard the RPi/S03 versus the BBB/S03 combo's, I couldn't tell one from the other.

Unfortunatly the form factor I'm planning for the R-2R will not allow for a S03.

 

[acko]

Acko, have you tried this with 90deg. header pins so that it stacks onto the BBB P9 header vertically; looks like just a little surgery needed in the bottom left corner. I ask because in a horizontal arrangement the outputs will be further away from my SO3 board and I want to keep all connections as short as possible.

Anyway, I'm as keen as mustard to get my hands on one....

Is the current GB list for these boards or the Supercape. You've muddied the waters with your little surprise.

Ray

Ray, it will fit with vertical mount - no need to trim anything. You can try this with the adapter board that you already have. It has similar cut on the mounting side. New board will go into fab early next week. Samples for tests, a couple of weeks later ... not long to go!

This SuperCape list will do. As I said before will advise those on the list about the changes and options.

 

[acko]

I'm expecting to recieve the R-2R dac in the post on monday.

The dac already has an isolator and reclocking. Would it not be detrimental to put two isolators/reclockers in series? Synchronised clocking with the BBB, would still be an advantage.

I've heard the RPi/S03 versus the BBB/S03 combo's, I couldn't tell one from the other.

Unfortunatly the form factor I'm planning for the R-2R will not allow for a S03.

No harm with cascaded re-clockers as yours will be. The final one (Soren's) DAC determines the overall performance.

S03 is still needed to provide the dual clocks for BBB, unless you plan to use the single clock of BBB for 48k based music only or your own dual clock feed for both 44.1/48k

Interesting report on the RPi vs BBB. Will check with others as well for similar comparison

 

[DQ828]

Fixed

 

[nautibuoy]

S03 is still needed to provide the dual clocks for BBB, unless you plan to use the single clock of BBB for 48k based music only or your own dual clock feed for both 44.1/48k

The Soekris DAC has 'masterclock' output and 'clock-select' input on it's I2S header so in theory it should be able to clock the BBB (with miero's Botic software) to retain native sampling rates.

Ray

 

[acko]

The Soekris DAC has 'masterclock' output and 'clock-select' input on it's I2S header so in theory it should be able to clock the BBB (with miero's Botic software) to retain native sampling rates.

Ray

Excellent! Is this already implemented? Any further details?

 

[mcluxun]

Excellent! Is this already implemented? Any further details?

http://www.diyaudio.com/forums/vend...-magnitude-24-bit-384-khz-91.html#post4197094

also in post 484

f I have to say it myself, the clocking scheme is actually very high performance and flexible.... Have mostly been discussed before but the thread is getting long, so here's a recap:

The DAC have a low jitter digital controlled oscillator (SiLabs si570), data is sent though a FIFO (with programmable lenght) and the FPGA and uC work together to measure incoming bitrate and adjust clock as needed, basically a digital PLL with very fast lock and very slow filtering. So the DAC itself only need serial data, word clock and bit clock, no master clock is needed, it will sync to whatever you feed it.

But the DAC can also output a master clock and do have a pin for selecting between 45.1584 and 49.152 Mhz (can be divided).

Same master clock output is also used when connecting multiple DAC's, t.ex. for digital crossovers.

 

[acko]

Thanks! All good to go then direct to BBB (if these lines are active already in the current version of Soren's DAC) full Sync operation
I see no issues with this interface except that MCK from DAM 1021 is 45/49 and BBB can take 26Mhz max only, but then again we have seen reports of successful operation at higher frequencies. Says, "can be divided" (on the DAC itself) but how?

 

[stijn001]

The Soekris DAC has 'masterclock' output and 'clock-select' input on it's I2S header so in theory it should be able to clock the BBB (with miero's Botic software) to retain native sampling rates.

Ray

Clock division is on the development list, not yet supported, eventhough the pins are already there I've not yet heard of anybody giving them a try.

 

[Greg Stewart]

Ray, it will fit with vertical mount - no need to trim anything. You can try this with the adapter board that you already have. It has similar cut on the mounting side. New board will go into fab early next week. Samples for tests, a couple of weeks later ... not long to go!

This SuperCape list will do. As I said before will advise those on the list about the changes and options.

Sorta like this?

Sorry, did this back in Dec & never around to posting it.

Greg in Mississippi

 

[nautibuoy]

Clock division is on the development list, not yet supported, eventhough the pins are already there I've not yet heard of anybody giving them a try.

There's one way to find out if it works....

I think ChanH is feeding his BBB circa 45MHz clocks without subdivision and reported good results.

I plan to try the Soekris with BBB/Botic myself but not for a few months as I need to get some other projects finished first.

Ray

 

[nautibuoy]

Sorta like this?

Sorry, did this back in Dec & never around to posting it.

Greg in Mississippi

Thanks Greg. Yes, similar to that, though I would rotate it 180 so that the board is on the other side of the P9 header with the ufl connectors facing P8.

Ray