What kind of a USB cable did you use in the box?
How does the female end mount on the wooden box?
A mico usb cable that I cut on one end, stripped the wires, and soldered to the barrel plug. Only +5 and GND are soldered to the barrel plug.
Surely you didn't have to solder that? I had some ladies in the lab do some work for me on micro USB connectors and they needed years of experience and expensive equipment ( microscope with a TV camera ) to do it.
OR... do you just use the USB for power?
Yes, USB is for power only. Makes it easy to unplug from switcher and plug into PC if needed.
Another thing... only one wire into the S/PDIF input... I assume the signal ground is provided by the USB then?
Yes
How does the female end mount on the wooden box?
A mico usb cable that I cut on one end, stripped the wires, and soldered to the barrel plug. Only +5 and GND are soldered to the barrel plug.
Surely you didn't have to solder that? I had some ladies in the lab do some work for me on micro USB connectors and they needed years of experience and expensive equipment ( microscope with a TV camera ) to do it.
OR... do you just use the USB for power?
Yes, USB is for power only. Makes it easy to unplug from switcher and plug into PC if needed.
Another thing... only one wire into the S/PDIF input... I assume the signal ground is provided by the USB then?
Yes
The biggest drawback of a Raspberry Pi for a streamer is that they are currently unavailable. It is certainly not measured performance. According to GoldenSound, this RPi based unit measured the best. Does that translate into sound quality?
IMHO... NO.
He didn't even try an Android phone/tablet. Or even an iPhone/iPad.
There is a lot to say by running on batteries only.
I have a Raspberry 4 still new in the box. ;-) I have looked into using the hat interfaces but mostly I prefer the USB IF. It isolates the DAC from the "streamer" better.
Besides, he's chasing at windmills. Who cares about USB jitter? The audio data is burst and reliable. The DAC will reclock it out. I think he got an RME DAC in there... huh? Once again.. people looking at the wrong things.
He didn't even try an Android phone/tablet. Or even an iPhone/iPad.
There is a lot to say by running on batteries only.
I have a Raspberry 4 still new in the box. ;-) I have looked into using the hat interfaces but mostly I prefer the USB IF. It isolates the DAC from the "streamer" better.
Besides, he's chasing at windmills. Who cares about USB jitter? The audio data is burst and reliable. The DAC will reclock it out. I think he got an RME DAC in there... huh? Once again.. people looking at the wrong things.
A HiFiBerry DAC Pro+ reclocks everything with two onboard clocks. Works great if you have a RPi4. If you want to go the extra mile, feed it clean 5 volts and not use power from the Pi. It’s an easy mod.
Run the RPi from a battery is not a problem, buy I think a properly designed power supply sounds better. What is the difference between an RPi and Android phone/tablet? Both use ARM processors. The nice thing about an RPi is that it can be easily "tricked out" with HATs.
The difference?
The entire architecture, that's it.
The nature of the cores are the last thing you should worry about.
The entire architecture, that's it.
The nature of the cores are the last thing you should worry about.
"Blown away" is the most common comment I get about ProtoDAC.
These days with poor availability of RPi, Android phone/tablet makes a lot of sense. What is the secret to Android architecture and sound quality?
I am looking into USB to I2S options for ProtoDAC. Do you have any recommendations?
These days with poor availability of RPi, Android phone/tablet makes a lot of sense. What is the secret to Android architecture and sound quality?
I am looking into USB to I2S options for ProtoDAC. Do you have any recommendations?
There is NO secret to Android "architecture"... it's just an OS.
If you want a secret, you go bare metal or use an RTOS. But even so, it won't really matter if the hardware is done right.
The "secret" per se is in the DAC hardware and the power supply: How they handle the ground plane, the accuracy of the decoding and the analog driving section.
Why do you want to deal with I2S? USB is a better interface to the DAC, it decouples the timing.
If you want a secret, you go bare metal or use an RTOS. But even so, it won't really matter if the hardware is done right.
The "secret" per se is in the DAC hardware and the power supply: How they handle the ground plane, the accuracy of the decoding and the analog driving section.
Why do you want to deal with I2S? USB is a better interface to the DAC, it decouples the timing.
I2S with very short wiring so PCBs in one box wins from USB (often). It saves a few conversion steps.
BTW a few devices in this thread are built in unshielded wooden boxes. We are electrically gifted people, we don't really do that do we?
BTW a few devices in this thread are built in unshielded wooden boxes. We are electrically gifted people, we don't really do that do we?
What is the difference between an RPi and Android phone/tablet?
"The difference? The entire architecture, that's it." Would you please elaborate. What aspects of the architecture are most important to the sonic qualities?
Why do I want to deal with I2S? Because the TDA1387 requires I2S input.
"The difference? The entire architecture, that's it." Would you please elaborate. What aspects of the architecture are most important to the sonic qualities?
Why do I want to deal with I2S? Because the TDA1387 requires I2S input.
In my case (pun intended) I was worried about a shielded box blocking the WiFi signal. Gifted? I'll assume you're referring to someone else 🙄
Look, it's truly simple.
Android is an outgrowth of Linux which grows out of Unix. It is a space partitioned OS with threads and processes. It has interrupts and IPC mechanisms for messaging and synchronization. That's IT.
It has NOTHING to do with Hardware.
Raspbian is in the same boat.
The BSP ( Board Support Package ) is used to allow the OS to run on a particular board. The BSP knows about the hardware and provides APIs to the OS. Think of the OS as an application on steroids.
Now, when Android is used on a phone, it tends to use a set of common interfaces (API) and binaries so that applications are relocatable and do not have to be rebuilt for a given phone.
Hardware.. well the SoCs are different. They have varying types and numbers of cores, matrices, busses, modems, multimedia, graphics, etc... they are all different but the applications running under Android do not see that, surely you don't want to recompile and rebuild your applications for each phone, huh? For one thing, no manufacturer (phone and SoC) will ever release the internal memory map, registers and header/build files require for an application programmer to compile from scratch a binary.... That's the point of using relocatables with a standard API.
If you use I2S then your interface is working at a lower layer than USB. USB is more of a logical network interface, a USB device might within itself use I2S, see? Indeed, some SoCs will expose I2s within the SoC itself... but that's at a level you have no access -well, unless the SoC and SBC ( single board computer) offer an I2S interface.
An application using the I2S path, would talk to the OS via an Adaption Layer which drives the hardware via the BSP. Stuff like interrupt handlers and processes and threading can be specified and controlled by an application. Indeed, an application can specify interrupt handlers as well, but that would be a very rare thing. In the Linux world, including Android, the interrupts are broken into a low and high level. It would be incredibly rare for an application to provide a low level interrupt routine as that would require intimate knowledge of the hardware. The high level ISR is a logical API interface.
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FWIW, the ESP32 can also output I2S. Here's an example connecting the ESP32 to a PCM5102A. Even though the ESP32 can provide MCLK, I prefer to ground the SCK (MCLK) pin of the PCM5102A, which triggers the chip to generate it's own SCK from it's internal PLL based off the BCK coming from the ESP32.
Do you solder the wires? Are push in connectors, or even Molex connectors, available?
Where is the analog signal output?
it'd be interesting if you could put in a switch that allows you to control the SCK source.
Where is the analog signal output?
it'd be interesting if you could put in a switch that allows you to control the SCK source.
Do you solder the wires? Are push in connectors, or even Molex connectors, available?
I soldered the wires to the ESP32, but only soldered female connector to the DAC.
Where is the analog signal output?
It's the 3.5mm jack. There are also via's along the side to connect to RCA jacks.
it'd be interesting if you could put in a switch that allows you to control the SCK source.
If the PCM5102A doesn't sense a valid clock on SCK (if it's grounded), it will revert to it's own PLL. I guess one could have a switch to toggle between a MCLK and ground to allow for a four wire vs three wire input.
I soldered the wires to the ESP32, but only soldered female connector to the DAC.
Where is the analog signal output?
It's the 3.5mm jack. There are also via's along the side to connect to RCA jacks.
it'd be interesting if you could put in a switch that allows you to control the SCK source.
If the PCM5102A doesn't sense a valid clock on SCK (if it's grounded), it will revert to it's own PLL. I guess one could have a switch to toggle between a MCLK and ground to allow for a four wire vs three wire input.
im with @tonyEE
really not rocket surgery.
You just use a pad or phone download the app connect to wifi.
all done.
You can get brand new pads or phones rather cheap these days
and some older phones still have way more potential.
you dont need service or contract.
Wifi.
I actually use service less phones for GPS as well
you dont need service to hit the satellite. Just
download area maps...all done.
really not rocket surgery.
You just use a pad or phone download the app connect to wifi.
all done.
You can get brand new pads or phones rather cheap these days
and some older phones still have way more potential.
you dont need service or contract.
Wifi.
I actually use service less phones for GPS as well
you dont need service to hit the satellite. Just
download area maps...all done.
I suggest that you look at the videos of Gabster on Youtube. He has made both a complicated DYI streamer and recently published a simple version of a DIY streamer that is based on Rpie.
Thanks Menchs
Here is a link of my last video this one is intended for new DIYers more Videos will be out soon with some upgrades also see my other videos for more complicated ones RPI based. Feel free to share links on other forums.
I made a RPi + Allo Kali reclocker giving native I2S into my DAC.
Used Lan, Volumio as media server SW.
Fed it linear power. Turned all unnecessary off.
Sounded pretty good.
Used Qobuz. Spotify occasionally.
Ultimately though, Bubble UPnP as media server, into renderer Sonore Ultrarendu into a Gustard U18 reclocker kicked RPi etc firmly into touch, sound quality wise.
Cost a lot but though..
Used Lan, Volumio as media server SW.
Fed it linear power. Turned all unnecessary off.
Sounded pretty good.
Used Qobuz. Spotify occasionally.
Ultimately though, Bubble UPnP as media server, into renderer Sonore Ultrarendu into a Gustard U18 reclocker kicked RPi etc firmly into touch, sound quality wise.
Cost a lot but though..