Hope you can get it fixed soon, there are plenty of components in the chain that need a single low noise high quality 5V supply.
Eh.
You're completely off track.
No. I am not talking about soldering wires. I am not even close to this phase. And I probably won't ever get there under
current conditions.
What I'm saying is that people #metoo will simply not pull all their uUSB/USB-C cables all the time because Shanti
seems to cause certain issues at power-down.
It seems you even havn't understood the issue at all.
Attach your ear to the Katana caps, the big ones. And then turn off Shanti.
The sound you should (& I ) hear simply tells me that the lifetime of that
attached device might be limited if continuing this way..
What's so difficult to think about cutting the DC rails at power down and than
you'd discharge the caps via bleeding R. Simply consider it for Shanti Rev2.0.
Just have a closer look at it. Perhaps and hopefully there's a simple explanation to it. I'm all ears.
Cheers
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How about add an output disconnect switch to Shanti? It would raise output impedance a little and probably decrease reliability a little, but if customers want it and are willing to pay a little more to have it...
Rather late in the game to make changes though. Might have to be Shanti MkII.
Rather late in the game to make changes though. Might have to be Shanti MkII.
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cdsgames
How does the Nirvana perform on a single psu unit like the Digione player? Is there a big difference between it and a standard smps? I hear the difference between std. allo psu and a grounded iFi unit, but the iFi is far from perfect.
Shanti is great for 2 psu digione sig/boss/katana, maybe it just needs a recommended 'power off' protocol to avoid the slow power drain issue.
How does the Nirvana perform on a single psu unit like the Digione player? Is there a big difference between it and a standard smps? I hear the difference between std. allo psu and a grounded iFi unit, but the iFi is far from perfect.
Shanti is great for 2 psu digione sig/boss/katana, maybe it just needs a recommended 'power off' protocol to avoid the slow power drain issue.
Ah, fair enough - I did wonder so thanks for the clarification. Alu casing would be handy but not essential in the short term, but I'll probably build it all into a Modushop case eventually
Eh.
You're completely off track.
Cheers
No Soundcheck. You are.
I am done with you .
. Thx you for all your ideas but I will no longer answer your perceived problems .
Good luck you to you .
Digione and Digione Sig was tested with Shanti and there is no problem on power on or off. You can use the AC switch or DC barrel disconnect
How will Nirvana perform on Digione ? Thats a tough question , I would say better then IFI not as good as Shanti
I think this was a very surprising comment. I have been following what I find was a very constructive dialog between you and Souncheck so I simply don't understand your reaction. And btw - I totally agree with Soundcheck. Hoping aense and courtesy will arrive again. BR, Per
* Thx for supporting my position
* Yep. I've been as surprised as well.
I even received a private mail that there'll be no further offline communication.
That offline communication was also used to discuss e.g. driver issues, which led to corrections in the (recent) past.
* Yep. I try to be constructive. I usually make sure to follow the "constructive criticism" principle. Criticism (positive and negative) is followed by advise. I'd never bash a product. I'm simply interested in getting better and flawless products - as most of the fellow inmates are.
* Since Allo/cdsgames obviously has a problem with my feedback, even
though I've also been part of the beta-tester/reviewer crowd for certain products,
I'll send all the FOC Allo products I still have here for FOC testing and integration work back.
It doesn't make sense to keep them under these conditions.
And finally. I very well understand that Allo is p...ed off with such feedback.
But instead of fighting the messenger, they'd better look into the subject outlined in the message.
All the best
SC
Hi PDB
This is not out of the blue. Soundcheck and I had problems before and we solved them privately .
You seem to think that our dialog was constructive . I tried to think the same all this time , but it is not .
In this hobby or ours , there are some people that have strong opinions . As long as they back it up with ideas and knowledge they are welcome (even if ideas might be controversial)
In this particular case , Soudcheck is reporting that when turning off AC switch on Katana he can hear a "nasty sound" . Yeap we hard it as well . Of course if you disconnect the DC cable Shanti has no sound difference than any other PSU in the world .
Now lets examine the cause .
Any analog stage has opamp with dual rails . The DC/DC convertor has enable pins and both rails will ramp up (or down) at slightly different speeds . (case of Khadas boards , cheaper Topping) and opamps will create a sound. So thats the cause. Imbalance between the positive and negative rails. Since Shanti is ramping up rather the same but down slower (and of course we have bleeder R) the imbalance in the rail is exacerbated .
Further on the best DACs on the market , DC/DC convertors are further cleaned using separate LDOs that might have the enable pin turn off at 0.5V vs another than turns off at 0.8V. (Like Katana and best Toppings). When Shanti is ramping down (slowly) the rail diff is amplified.
So the solution on those DACs (and those DACs only) is to use DC disconnect .
Then he posted this :
"And even if you do not experience these rough conditions on the other boards, it doesn't mean that these boards won't get tortured in a similar way"
Well , he is absolutely wrong . A slow ramp up/down is not a bad thing . Best LDOs have "slow ramp up" designed into them
Unless you have a dual rail on the board (opamp ) any DC/DC convertor (RPI for example) or LDO , will behave even better with slow ramp up/down .
So I have tried to give the solution (remove the DC cables) a few times. This is the responses that I got :
"You gotta be kidding!
""Eh.
You're completely off track."
"It seems you even havn't understood the issue at all." ....ok
As I said PDB this is not the first time. Last time his comments told me that he is not "my mom"... at what point I have to say it ? Enough is enough.
You are correct courtesy is important . But courtesy is to be reciprocated , thats my opinion .
I am rather patient , but the discussion with Soundcheck is not constructive . In this beautiful first wold of ours , we sometimes have issues that are simply our own making .
Thank you for explaining your side of things. Still, wouldn't a simple on/off switch on the DC side solve / reduce the problem and be cheap to implement in the next series - and a short note explaining the problem and the correct way to turn off / disconnect the psu be the preliminary solution for people owning the current version? I am not an engineer but I have learned a lot from your brilliant explanations and Soundchecks insight and questions. No need to cut off SC thinks naive me May peace and compromise find its way again. BR, Per
May peace and compromise find its way again. BR, Per
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I do not.
Twisting and changing the stories. Denying everything. Simply ignoring facts.
Behind the curtain doing the exact opposite.
And then putting blame on these people who simply do not accept such a BS.
Example1:
In the heated slew-rate/transient response discussion I brought up.
I said that these parameters need to be measured and belong into a datasheet.
Your response: It's good enough. Trust me.
Of course I don't trust you on such a response. I am an engineer. And as an engineer I consider such an answer a slap in the face.
In the end it turned out - you admitted it over here - you wouldn't even know how to measure a slew-rate. You basically hadn't done your homework.
Meanwhile you ordered equipment to be able to run these kind of measurements.
Why? Everybody can guess that.
But of course its me why the discussion got heated.
Example2:
Shanti powerdown issue. First it was a non-issue to you.
Then it was "we can't add a MCU because that'll cause noise". Ooohk. That
sounds different.
Now it's "yes we heard the issue too" - the Katana cap noise.
But it's only on analog.
Hmmh. It's a buffer cap on a digital board that also provides an analog rail.
And now you can see people start talking about switches. My simple
suggestion was to add a relay to the Shanti DC rail output to avoid any potential issues. Not to forget add a discharging-R.
And not a traditional bleeding R which will take a week to discharge the caps.
In the end it's a supercap supply with a huge passive/non-regulated cap
on the output rails. I'm not aware that anybody else is offering such a
device. Therefore to me it's not a surprise that this or that issue pops up.
***
I btw never talked about DC/DC converters. I never talked about rampdown.
And I do not consider your story around it relevant. You simply can't predict
what devices people attach to Shanti.
I said it takes forever until the PI LEDs turn off with Shanti. And I said.
Don't pull the SD-card during that phase! You might get your card corrupted.
Yes you could pull the uUSB cable. Great solution!
Again twist and turns. All starting by trying to shut me down by claiming a "non-issue"
############
Sorry Ioan. I have better things to do then this.