Member
Joined 2018
Hello DIY-Audio lovers!
I started planning a new FreeDSP project named "FreeDSP OCTAVIA".
An ADAU1452/1466-based Octal(8ch) output board that has various input interfaces.
The attached current idea block diagram feels too much for ordinary use cases...
So I'd like to reduce interfaces after hearing your opinions, suggestions, and ideas.
One more application for USB-DAC, which has 4 differential DAC processing. An additional board will be required for this application.
I also attached a similarly designed board picture I made a few years ago. The New board will be a little bit expanded design from this...
CyberPit
I started planning a new FreeDSP project named "FreeDSP OCTAVIA".
An ADAU1452/1466-based Octal(8ch) output board that has various input interfaces.
The attached current idea block diagram feels too much for ordinary use cases...
So I'd like to reduce interfaces after hearing your opinions, suggestions, and ideas.
One more application for USB-DAC, which has 4 differential DAC processing. An additional board will be required for this application.
I also attached a similarly designed board picture I made a few years ago. The New board will be a little bit expanded design from this...
CyberPit
Attachments
Last edited:
Member
Joined 2018
A Happy new year to everyone!
Now I'm thinking about the board layout before designing the circuit.
Small short parts are not applicable. I just wanted to know the size/dimensions of the board...
100mm x 178mm minimum (100x 226mm space required with Raspberry-Pi)
CyberPit
Now I'm thinking about the board layout before designing the circuit.
Small short parts are not applicable. I just wanted to know the size/dimensions of the board...
100mm x 178mm minimum (100x 226mm space required with Raspberry-Pi)
CyberPit
Attachments
Dear Pit...that's a great new.!!!
That what i was looking for since a long time ago.
You know we had variuos message exchange while you was developing the Catamaran DSP.
The use of the ADAU 1452 would be a must for people who wants to test FIR Filters as well.
Please..Do not forget balanced outputs..!!!
That what i was looking for since a long time ago.
You know we had variuos message exchange while you was developing the Catamaran DSP.
The use of the ADAU 1452 would be a must for people who wants to test FIR Filters as well.
Please..Do not forget balanced outputs..!!!
Member
Joined 2018
Thanks for cheering on this project.
Now I started designing schematic circuit diagrams.
Attached PDF is a draft of PSU and Raspberry-Pi slot part schematic.
I intend to use Moode Audio Software for Raspberry-Pi application. Running as a HIFIBERRY DAC+ZERO.
Attached PDF is a PSU and Raspberry-Pi slot part schematic. I would like to know the following device's pin assignment suggestions or optional ideas...
The current design is as follows.
Device: Default/(Optional)
IR-Remote Sensor: GPIO26/(GPIO25)
Shutdown-Restart Button: GPIO17/(GPIO26)
SPI for USB/IP Configuration: SPI0
I2S LRCK: pin35
I2S BCLK: pin12
I2S DATA: pin40
Expecting something useful...
CyberPit
Now I started designing schematic circuit diagrams.
Attached PDF is a draft of PSU and Raspberry-Pi slot part schematic.
I intend to use Moode Audio Software for Raspberry-Pi application. Running as a HIFIBERRY DAC+ZERO.
Attached PDF is a PSU and Raspberry-Pi slot part schematic. I would like to know the following device's pin assignment suggestions or optional ideas...
The current design is as follows.
Device: Default/(Optional)
IR-Remote Sensor: GPIO26/(GPIO25)
Shutdown-Restart Button: GPIO17/(GPIO26)
SPI for USB/IP Configuration: SPI0
I2S LRCK: pin35
I2S BCLK: pin12
I2S DATA: pin40
Expecting something useful...
CyberPit
Member
Joined 2018
Hi DIY freaks!
Here's version Zero, the draft idea of FreeDSP OCTAVIA. (Just for estimating PCB size)
I'm considering adding 4 times FreeDSP 10P I2S headers, differential Line-driver or balanced line driver.
But the cost will increase drastically if add the 8 times line-driver circuit, muting circuit, and Bi-polar power supply.
An additional constraint is the PCB does not have so many vacant spaces...
So, I'm feeling adding the line driver is not a good idea. Maybe we need some compromise or options.
Feel free to comment(s).
CyberPit
Here's version Zero, the draft idea of FreeDSP OCTAVIA. (Just for estimating PCB size)
I'm considering adding 4 times FreeDSP 10P I2S headers, differential Line-driver or balanced line driver.
But the cost will increase drastically if add the 8 times line-driver circuit, muting circuit, and Bi-polar power supply.
An additional constraint is the PCB does not have so many vacant spaces...
So, I'm feeling adding the line driver is not a good idea. Maybe we need some compromise or options.
Feel free to comment(s).
CyberPit
Attachments
Dear Pit.
Some considerations from my side.
1) Raspberry connector..why?
Who's using a Raspberry with Moode can use the built in Camilla DSP..in my opinion i will remove it.
I would stay with AES IN/OUT..Analog and USB for people using the Raspberry..in this case they could use the OCTAVIA as a Multichannel dAc..
2) Amanero interface..why?
Let people to use their prefered usb interface...Having the AES IN and Out would make the OCTAVIA super flexible..and less complicated i suppose.
3) DAC
Why not the AKm4458..?
To have 8 balanced outputs from one board?
What do you think guys?
Some considerations from my side.
1) Raspberry connector..why?
Who's using a Raspberry with Moode can use the built in Camilla DSP..in my opinion i will remove it.
I would stay with AES IN/OUT..Analog and USB for people using the Raspberry..in this case they could use the OCTAVIA as a Multichannel dAc..
2) Amanero interface..why?
Let people to use their prefered usb interface...Having the AES IN and Out would make the OCTAVIA super flexible..and less complicated i suppose.
3) DAC
Why not the AKm4458..?
To have 8 balanced outputs from one board?
What do you think guys?
Member
Joined 2018
Hi Maurizio,
This project is not designed for High-End Audio enthusiasts, just for poor DIY freaks.
Why Raspberry-Pi Slot?
The following concepts are very important for me and may be some DIY freaks.
1. Want to build a One-body WiFi-ready networked media player with enough quality DAC(s).
2. Want to use the wireless Airplay.
3. 1U(44mm) sized stylish Low profile Rasp-pi Audio system capability
4. USBi/IP support
Why have an Amanero Slot?
Just 20P socket is enough to have USB-Audio interface.
I guess various audio interfaces are welcome.
Neither the LVDS-HDMI nor AES/EBU interface is not fit for Poorman's DIY items.
Those are not suitable for this project.
About AKM chips.
1. AKM chips are still scarce on earth. Cause of the accident of fire damage in 2020.
2. Differential output DAC requires external differential buffer circuits (8 times!, Huge PCB Spaces required)
3. Twice to three times more expensive
4. 8 times Serial control requires and software development required
5. JLPCB's PCBA is not available. (Anyone can hand soldering 8 times 64-pin QFP chips safely?)
We need to some compromises to realize reasonable but enough quality products anyway...
But I remember, you are mentioning about Balanced Output.
CyberPit
This project is not designed for High-End Audio enthusiasts, just for poor DIY freaks.
Why Raspberry-Pi Slot?
The following concepts are very important for me and may be some DIY freaks.
1. Want to build a One-body WiFi-ready networked media player with enough quality DAC(s).
2. Want to use the wireless Airplay.
3. 1U(44mm) sized stylish Low profile Rasp-pi Audio system capability
4. USBi/IP support
Why have an Amanero Slot?
Just 20P socket is enough to have USB-Audio interface.
I guess various audio interfaces are welcome.
Neither the LVDS-HDMI nor AES/EBU interface is not fit for Poorman's DIY items.
Those are not suitable for this project.
About AKM chips.
1. AKM chips are still scarce on earth. Cause of the accident of fire damage in 2020.
2. Differential output DAC requires external differential buffer circuits (8 times!, Huge PCB Spaces required)
3. Twice to three times more expensive
4. 8 times Serial control requires and software development required
5. JLPCB's PCBA is not available. (Anyone can hand soldering 8 times 64-pin QFP chips safely?)
We need to some compromises to realize reasonable but enough quality products anyway...
But I remember, you are mentioning about Balanced Output.
CyberPit
Hi Pit.
Consider that who's playing with multichannel system like your..is anyhow approaching hiend..
But is your project..and of course it must fit your needs first.
Yes..balanced outputs could fit lot of class D amps.
This would be very useful in my opinion..having 8 balanced channel on one board would be a must.
Many thanks for your feedback and your efforts.
maurizio
Consider that who's playing with multichannel system like your..is anyhow approaching hiend..
But is your project..and of course it must fit your needs first.
Yes..balanced outputs could fit lot of class D amps.
This would be very useful in my opinion..having 8 balanced channel on one board would be a must.
Many thanks for your feedback and your efforts.
maurizio
Member
Joined 2018
Configuring SigmaDSP over TCP/IP seems a very attractive feature for me. (But it has not been tested yet)
Well, this project also focuses on my circuit design abilities.
Now I thinking about adding a balanced output capability. I do not want to use DRV134/135 from the point of view of its audio performance. So I will use OPA1632 chip for this project to satisfy all our needs. Using only one PCB design that fits all needs is a very difficult thing, but maybe I think I can do it for the following applications...
1. Simple PCM5102A output (Basic version)
2. Differential RCA output (Differential version)
3. Balanced output header (Balanced version)
4. High-performance DAC (Summing version)
if I try on this, having FreeDSP I2S header will be difficult, does anyone need it?
CyberPit
Well, this project also focuses on my circuit design abilities.
Now I thinking about adding a balanced output capability. I do not want to use DRV134/135 from the point of view of its audio performance. So I will use OPA1632 chip for this project to satisfy all our needs. Using only one PCB design that fits all needs is a very difficult thing, but maybe I think I can do it for the following applications...
1. Simple PCM5102A output (Basic version)
2. Differential RCA output (Differential version)
3. Balanced output header (Balanced version)
4. High-performance DAC (Summing version)
if I try on this, having FreeDSP I2S header will be difficult, does anyone need it?
CyberPit
Attachments
Hi CyberPit
Did not see this thread before I started something similar https://www.diyaudio.com/community/threads/4-in-8-out-dsp-using-adau1652.394439/#post-7233977
I just wanted a few more inputs so something like 4 in 8 out. Looking at using a CODEC chip like the AD1939 to save space and cost, and it actually have better spec than PCM5102A and PCM1808 ...
Did not see this thread before I started something similar https://www.diyaudio.com/community/threads/4-in-8-out-dsp-using-adau1652.394439/#post-7233977
I just wanted a few more inputs so something like 4 in 8 out. Looking at using a CODEC chip like the AD1939 to save space and cost, and it actually have better spec than PCM5102A and PCM1808 ...
Member
Joined 2018
Hi Baldin-San,
Well, I would be somewhat unique than the same. The biggest constraint is PCBA parts availability. The cost is the next factor but we can not ignore it as well.
AD1939 is a highly complex device, it's difficult to choose from the following reasons...
The current design is scalable from 2 in 8 single-end output, 2 in 8 differential output, 2 in 8 Balanced output. An optional I2S/TDM Input header is provided to expand 2 or more input channels. The minimum configuration does not require Raspberry-pi nor Amanero USB-input daughter card. Just ADAU1452/1466 can handle analog I/O and S/PDIF Input and output.
To kaameelis-San, the RCA pin Jack is still provided. And it can output common -GND or differential signals.
To Maurizio-San, eight Balanced output is provided! (Sorry, you need XLRs with cable. It's not on-board)
Attached snapshot is the current board design (almost 90% routed)
It was very hard to implement various configurations with one design, but I was almost there...
CyberPIt
Well, I would be somewhat unique than the same. The biggest constraint is PCBA parts availability. The cost is the next factor but we can not ignore it as well.
AD1939 is a highly complex device, it's difficult to choose from the following reasons...
- Full differential analog I/O requires its driver circuits and PCB spaces. (OPA1632 cost almost 3 USD.)
- Small chance of using 4 analog inputs for most of the use-case.
- Requires SPI controls.
The current design is scalable from 2 in 8 single-end output, 2 in 8 differential output, 2 in 8 Balanced output. An optional I2S/TDM Input header is provided to expand 2 or more input channels. The minimum configuration does not require Raspberry-pi nor Amanero USB-input daughter card. Just ADAU1452/1466 can handle analog I/O and S/PDIF Input and output.
To kaameelis-San, the RCA pin Jack is still provided. And it can output common -GND or differential signals.
To Maurizio-San, eight Balanced output is provided! (Sorry, you need XLRs with cable. It's not on-board)
Attached snapshot is the current board design (almost 90% routed)
It was very hard to implement various configurations with one design, but I was almost there...
CyberPIt