@TNT I know. I think there's a misunderstanding.
I numbered the things I'm going to do.
"4. Low distortion Discrete opamp".
I know OPA1612 is easy to get good measurement results,
but it's not fun, so I said I'll do it with Discrete.
And since AKM DAC has good performance, it's easy to be dominated by distortion.
That's why I said that you have to try hard not to do that.
Many people think Discrete opamp is snake oil, and I do too.
I know that, but I said in advance that I'm just doing it for fun.
If it's going to be the same as the boards sold in China, why would I spend time and money
making it? You should have a high-quality oscillator and Discrete opamp.
I numbered the things I'm going to do.
"4. Low distortion Discrete opamp".
I know OPA1612 is easy to get good measurement results,
but it's not fun, so I said I'll do it with Discrete.
And since AKM DAC has good performance, it's easy to be dominated by distortion.
That's why I said that you have to try hard not to do that.
Many people think Discrete opamp is snake oil, and I do too.
I know that, but I said in advance that I'm just doing it for fun.
If it's going to be the same as the boards sold in China, why would I spend time and money
making it? You should have a high-quality oscillator and Discrete opamp.
@jean-paul CHORD Electornics also used USB terminal.
Well, this part can be considered a little more
The linear power supply is too bulky and inefficient. I said I want an ultra slim design. "150x100x20mm ultra-slim CNC case"
And if you design it like this, you can use USB chargers or batteries that are lying around the house.
To be a little more precise about the design, it is a switcher-LC filter-LT3042.
Since it operates at 1.2MHz, it is okay to feed it to the opamp.
It will not be heard and will be filtered by power amp and mass of the speaker diaphragm.
Well, this part can be considered a little more
The linear power supply is too bulky and inefficient. I said I want an ultra slim design. "150x100x20mm ultra-slim CNC case"
And if you design it like this, you can use USB chargers or batteries that are lying around the house.
To be a little more precise about the design, it is a switcher-LC filter-LT3042.
Since it operates at 1.2MHz, it is okay to feed it to the opamp.
It will not be heard and will be filtered by power amp and mass of the speaker diaphragm.
It does not matter what person X, famous company Y uses USB micro as the subject is the USB micro connector being unreliable. Anyone that repairs stuff knows it is the most shitty connector around maybe a title shared with USB micro B 3.0 (that is practically always defective it seems). My guesstimation is that the tiny contacts are not suited for relatively high currents and/or hot plugging with inrush DC currents. It is also outdated and best forgotten. Sorry.
Wait till it does not make contact (most happening failure) or becomes high ohmic which both are not categorized under "quality". Terribly annoying. But of course have it your way. I also wonder where to find recent/new good quality USB micro based USB chargers as USB-C is the norm?! Anyway, if you add 2 PCB pads for + and - you will have a way out. Just well meant advice.
Wait till it does not make contact (most happening failure) or becomes high ohmic which both are not categorized under "quality". Terribly annoying. But of course have it your way. I also wonder where to find recent/new good quality USB micro based USB chargers as USB-C is the norm?! Anyway, if you add 2 PCB pads for + and - you will have a way out. Just well meant advice.
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I prefer anything else 1612 at AK4493 output. For ex as for me 1656 sounds much better
@Anatolii_A It's good. It also supports quad packages, so it seems convenient when building with fewer parts.
A Usb c connector would make more sense. More reliable and has been adopted as a 'standard' by the EU for the duties that were performed by micro usb. Also, its symmetrical, so reduced levels of swearing when you're trying to plug something in to it.
I don't buy micro usb based gear if I can avoid it.
FWIW the refreshed silent switcher has usb c.
I don't buy micro usb based gear if I can avoid it.
FWIW the refreshed silent switcher has usb c.
USB-C is convenient, no introductory errors for idiots.
But I much prefer the USB-B connector, capable of supporting the constraints of the snake-oil cable, very heavy.
Micro-USB is the most terrible connector, mini much better, Type-C is even better, but in audio - USB-B is still the standard.
Alex.
Alex.
Please make sure that the ripple from the switchers doesn't end up on the voltage reference and doesn't modulate the clock, otherwise it can mix (in the RF sense, that is, frequency convert) out-of-band quantization noise between 1.18 MHz and 1.22 MHz down to the band from 0 to 20 kHz.
@MarcelvdG Hi MarcelvdG, thanks for the advice.
The ripple is not observed even with maximum zoom in LTspice.
Switcher-LC-Filter-LT3042-Reservoir C seems sufficient.
If needed, I think adding a Bead before Bypass C would effectively isolate the Load Switching of other ICs.
Or could a local LDO REG be cost effective?
The ripple is not observed even with maximum zoom in LTspice.
Switcher-LC-Filter-LT3042-Reservoir C seems sufficient.
If needed, I think adding a Bead before Bypass C would effectively isolate the Load Switching of other ICs.
Or could a local LDO REG be cost effective?
OK I get it now - thanks. So you are making a discrete output stage - perhaps mimicking an OP-AMP schema...
//
This is not a semantically coherent sentence:
I can't understan what you are trying to say - sorry. And before what?
First there is a statement "you and jean-paul are correct in wanting to build", but it ends with a question mark which make me very confused. Maybe you mean if you are in a correct understanding that we are to build a 4497 DAC? is this what you mean?
How can wanting to build a AKM4497 DAC be "far away" from a thread named: "New AK4497SVQ Build!" 🙃
Anyways, no I'm not intending to build a 4497 based DAC. I'm just here because I'm curious... 🙂 but of course I would like to understand what I'm reading. But as you can understand, english in not my main language. Please ignore me 😉 and good luck!
//
I can't understan what you are trying to say - sorry. And before what?
First there is a statement "you and jean-paul are correct in wanting to build", but it ends with a question mark which make me very confused. Maybe you mean if you are in a correct understanding that we are to build a 4497 DAC? is this what you mean?
How can wanting to build a AKM4497 DAC be "far away" from a thread named: "New AK4497SVQ Build!" 🙃
Anyways, no I'm not intending to build a 4497 based DAC. I'm just here because I'm curious... 🙂 but of course I would like to understand what I'm reading. But as you can understand, english in not my main language. Please ignore me 😉 and good luck!
//
Also no builder as I have one. OP wants to build only one for himself AFAIK but posts it publicly. Probably some of the people looking/showing interest know some real life/practical (non simulated) deficiencies and want to warn the OP to prevent the OP from time and money loss so just well meant advice. A consequence of publishing a new design to the public.
@TNT
I keep saying this, but I made this thread to discuss with builders who want to build a new AK4497 news.
But I don't think you planned to do that. So I was just asking.
And I don't think we communicate very well verbally.
@jean-paul
I Perfectly understood. Right. Because I posted it publicly
You can advise, but did you give actual defect advice? It was just stories I didn't understand.
IMHO "buying a board made by someone else and putting a linear PSU together" is a PSU DIY, not a DAC DIY.
On the other hand, G's advice is in context and effective.
How many people on this site make it cheaper, higher performance than factory products?
As far as I know, this is a DIY community. Win against used Topping. You will reign as king
.
I keep saying this, but I made this thread to discuss with builders who want to build a new AK4497 news.
But I don't think you planned to do that. So I was just asking.
And I don't think we communicate very well verbally.
@jean-paul
I Perfectly understood. Right. Because I posted it publicly
You can advise, but did you give actual defect advice? It was just stories I didn't understand.
IMHO "buying a board made by someone else and putting a linear PSU together" is a PSU DIY, not a DAC DIY.
On the other hand, G's advice is in context and effective.
How many people on this site make it cheaper, higher performance than factory products?
As far as I know, this is a DIY community. Win against used Topping. You will reign as king
.
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IMHO there is no point in "winning against a used Topping", there is a point in doing better. Otherwise - just go and buy a "used Topping".
Alex.
Alex.
Why is that?
Topping mainly uses X-mos usb interfaces...
After trying... several, I much prefer the XING-CORE audio U30 usb interfaces (I never use coax or toslink)
The drivers are good and as a bonus with their application, you can adapt many parameters without knowing how to code or anything else, everything is relatively simple...
Then, I don't like their resin plastic power supply and their madness in resining the AOPs...😡
If you want a DAC that you like, DIY is possible...
Unfortunately the cost will not be competitive... But the pleasure is not measurable! 🙂