A external clock board for KALI is finally done. You can see the attached pictures that are Top, GND, Power and Bottom. The board has a internal layered capacitor. consists of GND, Power and Bottom, to block more than 500MHz of interference.
Attachments
low output passi i/v tda1543
it is normal that the output of a tda 1543 is very low, just add a simple i/v stage with sk 170 jfet you will have more output and sound so mutch beter as passive i.v
i get the maximum of the tda 1543 buy letting it work on 8 volt and my fet i/v had a seperate powersupply on 12 volt and even could be higher.
i don`t use a pream but only a nelso pass clone resistor ladder volume control with 128 steps, this sound 1 times better that with a preamp in teh signal path if i do tghat the magic is gone, to mutch degegradation. maybe you also could change the input resistors of you amp to make it more sensitive and will get much more power out of the tda 1543. for me teh tda 1543 is teh most musical dacchip ever made, upsampling kills teh musicalty and is in my opinion the biggest commercial audio lie it is all about buisinees. Philips is the inventor of teh cd player and made dacchips that came close to vinyl sound and in my opinion they alreddy made the best !!
it is normal that the output of a tda 1543 is very low, just add a simple i/v stage with sk 170 jfet you will have more output and sound so mutch beter as passive i.v
i get the maximum of the tda 1543 buy letting it work on 8 volt and my fet i/v had a seperate powersupply on 12 volt and even could be higher.
i don`t use a pream but only a nelso pass clone resistor ladder volume control with 128 steps, this sound 1 times better that with a preamp in teh signal path if i do tghat the magic is gone, to mutch degegradation. maybe you also could change the input resistors of you amp to make it more sensitive and will get much more power out of the tda 1543. for me teh tda 1543 is teh most musical dacchip ever made, upsampling kills teh musicalty and is in my opinion the biggest commercial audio lie it is all about buisinees. Philips is the inventor of teh cd player and made dacchips that came close to vinyl sound and in my opinion they alreddy made the best !!
I just received a isolation board from ALLO today. I install the isolation board between Sparky and KALI. The sound quality is greatly improved. It is a great isolation board and worth to buy. I need to use three independent power supply, respectively, to Sparky, isolator and KALI, because the current from KALI will not be supplied to Sparky through isolator.
Last edited:
Yes, it's not to have i2s isolator if the signal is from CDT. However, computers, such as Sparky outputs the signal with noise,so it need the i2s isolator to do isolation. Yes, the i2s isolator will cause jitter, but KALI has a buffer, it will reduce jitter, which this is why i2s isolator need to be installed between Sparky and KALI, not at KALI's output.
SMD soldering instructions for you
https://github.com/iancanada/DocumentDownload/blob/master/PowerSupply/ADM715X/SMDtutorial.md
That is true, yet Kali's fpga generates some nosie itselfs. The best would be to have rpi synchronus clocking with only flipflop alingment just in front of dac chip.This is the least noisy solution which tweastedpear audio is about to release.
The Cronus for Rpi.That is true, yet Kali's fpga generates some nosie itselfs. The best would be to have rpi synchronus clocking with only flipflop alingment just in front of dac chip.This is the least noisy solution which tweastedpear audio is about to release.
How do you know that CRONUS is better? Twisted Pear Audio did not notice jitter. Allo said KALI can reduces jitter to less than 4 pico seconds. Do you know how low it is? Cronus is not a big enough buffer so that Cronus can not reduce jitter, which Cronus output jitter is still very alarming degree. If the buffer is not big enough, equal to no buffer.
Hi cyrilliu,
I did not write to Cronus is better. I wrote: The best would be to have rpi synchronus clocking with only flipflop alingment just in front of dac chip. Not to go to much into details: DigiOne is pure synchronous clocking, does not have FPGA nor signal buffering (there are only clock buffers), and have 0.6ps jitter. They wrote somewhere once that they did not added I2S out into it, because they wanted to keep traces as short as possible (makes sense).
However, if they did add I2S out to DigiOne, you would have exactly what I wrote, isolation, synchronous clocking, reclcoking with flipflop with the least amount of noise (no fpga). In other words Cronus is trying to be DigiOne with I2S out. By design it should be better, but how it is going to be eventually ... I do not know.
I seriously do not see the need for signal buffering in synchronous design.
I think Kali came out in the times when synchronous rpi clocking was at very early development stage (or not even existing yet), that it is way they decided to use FPGA, because in such case they got everything under control and were totally independent from rpi and drivers (smart decision). If it was today they probably would have taken different decision, favoring synchronous master clock design like DigiOne.
Last edited:
Well I have no doubts you guys have a good understanding of the synch/asynch reclocking. I love your work! I bet what I wrote is just the tip of the iceberg.
I still consider rpi master clocking, isolation, flipflops to be the most straight forward solution and from technical point of view by design should be the least noisy since it has the least additional processing.
I think something like DigiOne I2S out or another way to say Kali master clocking (no fpga) would be a good addition to your product family.
I am wonder what keeps you away from doing this, whether it is technical, functional or business reasons? The only thing that comes to my mind is the functional overlap to what you already have: Kali. Yet maybe there is something behind that I do not understand ...
Cheers,
Last edited:
Hello,
Let me pop in the conversation. I'm in no way technically competent to join current debate but I'm interested in building RPI digital transport with I2S and Coax out. My question is would it be possible to stack up Kali with hdmi I2S out something like this: RaspDIGI LTE LVDS - Streamer I2S LVDS HDMI Audio-GD compatible - Audiophonics
and add the DigiOut also for coax, hopefully not messing the signal to much?
Let me pop in the conversation. I'm in no way technically competent to join current debate but I'm interested in building RPI digital transport with I2S and Coax out. My question is would it be possible to stack up Kali with hdmi I2S out something like this: RaspDIGI LTE LVDS - Streamer I2S LVDS HDMI Audio-GD compatible - Audiophonics
and add the DigiOut also for coax, hopefully not messing the signal to much?
Last edited:
You are correct, the design you spoke about its the simplest and straightforward. It has some problems though when you factor in delays from isolation barrier.
In the end , its not always about the simplest design. Its about creating a product that people will be excited about with a price that everyone can afford, basically a product that has value.
We can design a Kali for X00$...but this is not our market. Our market is people like you guys, that understand and find value (hopefully) in allo products.
Kali 2 design has started. Expect value , expect innovation , expect features that you did not know you needed (but you will have an eureka moment when they are announced)
In the end , its not always about the simplest design. Its about creating a product that people will be excited about with a price that everyone can afford, basically a product that has value.
We can design a Kali for X00$...but this is not our market. Our market is people like you guys, that understand and find value (hopefully) in allo products.
Kali 2 design has started. Expect value , expect innovation , expect features that you did not know you needed (but you will have an eureka moment when they are announced)
@cdsgames
Great! Can't wait for Kali 2 then Fingers crossed. What is the current planned expected release date?
I think with DigiOne you already drove many (if not most) out of business ...
As for propagation delays from isolator I think they are still lower than from FPGA ... But again I may not understand something here. Sorry to bother you with my questions. I am a "why?" inquisitive guy ...
Isn't this forum all about learning ...
Great! Can't wait for Kali 2 then
Fingers crossed. What is the current planned expected release date?I think with DigiOne you already drove many (if not most) out of business ...
As for propagation delays from isolator I think they are still lower than from FPGA ... But again I may not understand something here. Sorry to bother you with my questions. I am a "why?" inquisitive guy ...
Isn't this forum all about learning ...
If you need both then use Hifiberry digi+ pro. It has both: coax and i2s out.
Hifiberry is what I would call "good enough" design though e.g.: it takes dirty 3.3V power from Pi to power some parts. So to improve it you would need to use some isolation board (power it separately with some good regulator) to provide 3.3V clean power and isolate Hifiberry from rpi noise.
Last edited: