Asynchronous I2S FIFO project, an ultimate weapon to fight the jitter

[xaled]

No worries. The two wires are just for sending FifoPi information to MonitorPiPro. The other two wires are the Rxd and Vcc, which are not used for this application.
Ian

Got it, thank you!

 

[stew1234]

I have an unopened UCPure MKII if anyone is interested in buying it. Shipping from NY, US.

 

[67339]

Hello ,
I have the same one, never used but opened ( present from Ian) but i am in the Netherlands. Greetings Eduard

 

[Cerole]

Hello everyone,

I am currently trying to install the ReceiverPi DDC board.
My configuration should look like this:
1. RaspberryFree
2. Amanero USB Combo384
3. Receiver Pi DDC
4. Station Pi
5. FifoPi Q3
6. MonitorPi
7. TransportPiAES

First I want to connect my streamer with USB.
But I have a problem. I can not switch the ReceiverPi DDC to the USB input.
I have closed the pins 5-6 (J8), but nothing happens. MonitorPi shows "no signal".
Only the D8 LED is lit (Rasperry Pi as source).
Am I doing something wrong? Do I need the MonitorPiPro to switch the input?

 

[iancanada]

Here are some tips of building a digital audio system, as well as some troubleshooting cases.
Please have a read before you getting started.
Just hope they help.

https://iancanada.ca/blogs/news

Ian

 

[Cerole]

My system worked perfectly with the Receiverpipro. Now, I want to switch to DDC to use Amanero and USB.
I read your previous instructions, but they did not help me.
Is the board defective? How can I test it?

 

[iancanada]

@Cerole

You can send pictures to me at iancanada.mail@gmail.com
To see if I can figure it out for you?

Ian

 

[sbelyo]

Here's final Supercap box with shelf. There is a window in the bottom so you can put a layer of sound deadening material with a cover on it to protect the caps from touching any metal

 

[iancanada]

@sbelyo

That looks really nice.

3D print?

 

[sbelyo]

@iancanada Thanks, yes it is. That one has radiused edges and a window cut in the bottom. It will allow for some sound deadening material to be placed under the caps on the chassis without making contact. The bracket on top has it's own standoffs built in. I have 3 sets just like it plus one I want to test with spraying sound deadening on it. I can send you a set if you want. I have an extra one where the corners don't have a radius and it doesn't have a window in the bottom.

In a couple of weeks I'll have a chassis for up to three of these boxes and the complete Pi-less build. I still have to get some measurements right. I think I'll lay it out on some cardboard

 

[Oystein]

I cannot find any 18650 cells with an internal resistance <6 mohm, most are 7-15 mohm.

As these cells will be used for 3.3 V (on PurePi II) and when adding an UCconditioner with the correct capacitors how much should I really worry about not meeting the recommended specs for the 18650 cells ?

Or does somebody found a suitable supplier that does < 6 mohm and available in Europe ?

I found Sony Murata US18650VTC5A for a good price (7-15 mohm)

Thank you 🙂

 

[zabloc]

@Oystein
you have these:
https://www.batt-energy-shop.de/Akkus/Lithium-Akkus/lithium-werks-apr18650m1b-power-cells.html
they turned out to be excellent, <15 mOhm, I haven't found anything with less resistance

 

[sernikus]

No. ONLY LiFePO4 18650,,,,, read the manual .....

 

[gizmo3]

I cannot find any 18650 cells with an internal resistance <6 mohm, most are 7-15 mohm.

As these cells will be used for 3.3 V (on PurePi II) and when adding an UCconditioner with the correct capacitors how much should I really worry about not meeting the recommended specs for the 18650 cells ?

Or does somebody found a suitable supplier that does < 6 mohm and available in Europe ?

I found Sony Murata US18650VTC5A for a good price (7-15 mohm)

Thank you 🙂

Not exactly what you want but I'll use this one.


https://www.123accu.nl/123accu-IFR1...500-mAh-Li-FePO4-123accu-huismerk-i34374.html

 

[Oystein]

No. ONLY LiFePO4 18650,,,,, read the manual .....

Ahh .. I had read this already in this tread but looking for cells myself it is easy to forget to check if it was actually LifePO4.

@zabloc
Good to know the Lithium Werks are also available in the EU 👍

 

[andersos]

I cannot find any 18650 cells with an internal resistance <6 mohm, most are 7-15 mohm.

As these cells will be used for 3.3 V (on PurePi II) and when adding an UCconditioner with the correct capacitors how much should I really worry about not meeting the recommended specs for the 18650 cells ?

Or does somebody found a suitable supplier that does < 6 mohm and available in Europe ?

I found Sony Murata US18650VTC5A for a good price (7-15 mohm)

Thank you 🙂

The customer review for this battery states that it has very low internal resistance. I don't know if the other specs are suitable for PurePi II though
https://www.nkon.nl/jgne-18650-1100mah-33a-lifepo4.html

 

[Markw4]

By the time you add wiring and connections, the resistance is going to higher anyway. Also, the ESR of batteries is IME frequency dependent. They may have very low impedance at DC or low frequencies, but it is probably reasonable to expect ESR to go up with frequency.

 

[Raj1]

Yes, local decoupling is important. That said, there is something subjectively appealing about the sonics in comparison to most regulators.

 

[Markw4]

The biggest advantage of batteries is that they avoid problems with common mode noise, ground loops in AC power distribution systems, unpleasant regulator dynamics, etc. There can even be unwanted coupling between between secondary windings in power transformers. Once all those things are well controlled, then batteries usually end up sounding worse.

 

[Raj1]

IIRC someone posted measurements here a few years ago. The noise spectra of the batteries was under -150dB.