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Old 24th March 2014, 07:29 PM   #11
jcarr is offline jcarr  United States
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If you are willing to change motherboards, ASRock has announced an AMD Kabini-based motherboard with 19V input.

AnandTech Portal | ASRock?s AM1 Kabini Motherboards Announced, including 19V DC-In Model

Zotac's Atom-based D2550-ITX-B also has 19V input (Zotac used to have a motherboard with 12V input that could be powered with SLA batteries, but I didn't find it now).

mini-itx.com - store - Zotac Mini-ITX Motherboards

And, Japanese manufacturer Fidelix is in the process of launching a low-noise power supply for notebook compouter applications (page is in Japanese, need to use a translator)

Power Supply
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Old 25th March 2014, 07:23 AM   #12
BonkM is offline BonkM  Canada
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Quote:
Originally Posted by lexer98 View Post
10A is too little for your computer ... minimum a 12V @ 25A transformer and computers PSU don't have 1.65V rail that is generated by the MB

Simple solution is buying a Pico-ITX power supply ... something likes this 250W M4-ATX Smart Power Supply for Carputers ... and feed it with your lineal power supply
I was talking about 10A on just the 12V rail. As long as I have separate supplies for each voltage I think that'll be OK. I don't have a GPU and the TDP on the i5 is 65W. 65W off 120W (12V @ 10A) should make for a nice, lazy demand. Then I'm looking at 5A on the 5V, 3A on the 1.65V, and 4A on the 3.3V.

As for the 1.65V, that's a dedicated supply for the RAM. The motherboard does supply that voltage to it because that's what they're rated at. I may have to cut into some supply, but I've read in a few places about the idea of direct supplying the RAM.

And the PICO, thanks for the idea, but since it's a switching supply, I'm going to stay away from it. Feeding linear right into something that's going to turn it into different voltages via switching isn't the plan I had in mind. It would be easy for start up timing, which I need, but wouldn't meet my other requirement.

Quote:
Originally Posted by analog_sa View Post
It is not a good sounding solution at all. Something similar to the Pico (Nano) prompted me to build a linear supply. Admittedly, for a very low power i3, but it made a very substantial difference soundwise. There was a thread about it somewhere...
Hey Analog, thanks for commenting in. I actually had your old thread open and finished reading it just before you posted. What a funny coincidence. From what I've read you're not alone in your experiences. Anyone who has taken the time to work the PICO out of their powering setup has claimed it made a difference for the better. I'm going down that path too.
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Old 25th March 2014, 07:26 AM   #13
BonkM is offline BonkM  Canada
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Quote:
Originally Posted by jcarr View Post
If you are willing to change motherboards, ASRock has announced an AMD Kabini-based motherboard with 19V input.

AnandTech Portal | ASRock?s AM1 Kabini Motherboards Announced, including 19V DC-In Model

Zotac's Atom-based D2550-ITX-B also has 19V input (Zotac used to have a motherboard with 12V input that could be powered with SLA batteries, but I didn't find it now).

mini-itx.com - store - Zotac Mini-ITX Motherboards

And, Japanese manufacturer Fidelix is in the process of launching a low-noise power supply for notebook compouter applications (page is in Japanese, need to use a translator)

Power Supply
Thanks for the links, I'll have to give my Japanese a run for it's money and see how much I can still understand

As for changing motherboards, I can't see myself doing it. I don't want the full form factor, but I do need the PCIe slots. I need at least 2 on the board for my cards, and possibly 3 for one I might get down the line. So there's not much room to move on that point. Thanks for the ideas, though.
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Old 25th March 2014, 09:11 AM   #14
Julf is offline Julf  Europe
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So just to be clear, you are worried about using a switching power supply to feed something that only consists of switching circuits?
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Old 25th March 2014, 04:56 PM   #15
lexer98 is offline lexer98  Argentina
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Quote:
Originally Posted by BonkM View Post
I was talking about 10A on just the 12V rail. As long as I have separate supplies for each voltage I think that'll be OK. I don't have a GPU and the TDP on the i5 is 65W. 65W off 120W (12V @ 10A) should make for a nice, lazy demand. Then I'm looking at 5A on the 5V, 3A on the 1.65V, and 4A on the 3.3V.

FIRST ! ... COMPUTER PSU DON'T HAVE ANY 1.65v
RAIL (I wrote it three times)
The MB, IGP and peripherals consume energy .... TDP (thermal design power) is the maximum amount of heat that can generate CPUdoes not mean that the CPU consumes 65W, indeed your PC with the CPU at Full Load @ stock speed should consume arround 90-100W.
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Old 26th March 2014, 07:28 AM   #16
BonkM is offline BonkM  Canada
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Quote:
Originally Posted by Julf View Post
So just to be clear, you are worried about using a switching power supply to feed something that only consists of switching circuits?
Funny, right? I suppose I'd compare it to saying, I'd rather stick with just getting punched in the face(onboard mobo switching circuits) then adding getting kicked in the bag(additional switching supply, PICO) as well.

Quote:
Originally Posted by lexer98 View Post

FIRST ! ... COMPUTER PSU DON'T HAVE ANY 1.65v
RAIL (I wrote it three times)
The MB, IGP and peripherals consume energy .... TDP (thermal design power) is the maximum amount of heat that can generate CPUdoes not mean that the CPU consumes 65W, indeed your PC with the CPU at Full Load @ stock speed should consume arround 90-100W.
Thank you, Lexer98. I guess I don't know as much as you do about computer electronics and I've used the wrong terms. Please read the following link to see what I'm talking about with the 1.65V going to the RAM.
Audio Asylum Thread Printer

What you will find is that someone has independently powered their RAM via a linear power supply, just like I had said I wanted to do. I am aware that there is no socket (like P24 or P4) to plug this rail into, but I will make it none the less and patch directly into that section of the motherboard, just as the other poster did in the link. Do you understand what I mean now?

Besides that, I have looked on the AMB site at the Sigma11 and Sigma22 threads and will be using 3 Sigma 11's to make the 5V, 3.3V, and 1.65V and then 1 Sigma 22 to make the +/-12V.

The for toroidal transformers for the power, I'm still trying to figure it out, but have so far found something like this:

Transformer #1.
30VCT (15v-0-15v) @ 10A (from Primary)
10V in parallel @ 7A or 5VDC (from Secondary)

Transformer #2.
9V in parallel @ 5A or 3.3VDC (from Primary)
8V in parallel @ 3A or 1.65VDC (from Secondary)

I'm still trying to understand the actual Primary and Secondary output part, but I've contacted a custom toroidal manufacturer and explained what I'm looking for, so hopefully he can correct any misconceptions I have. Feel free to do so here, though, in case you see something out of place.

I really hope I can squeeze all that out of just 2 toroidal transformers, I really don't want to have to use 1 toroidal for each voltage. It would destroy my plan for the case I'm looking at using that comes from the same line as my Audio PC case. It's an extruded aluminum one.
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Old 26th March 2014, 07:57 AM   #17
Julf is offline Julf  Europe
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Quote:
Originally Posted by BonkM View Post
Funny, right? I suppose I'd compare it to saying, I'd rather stick with just getting punched in the face(onboard mobo switching circuits) then adding getting kicked in the bag(additional switching supply, PICO) as well.
Sure - it is your hobby after all, and I guess "if it is worth overdoing, it is worth overdoing" applies.

Looking forward to your results - are you planning on posting any "before" and "after" measurements?
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Old 26th March 2014, 09:56 AM   #18
sesebe is offline sesebe  Romania
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So, to understood well, you have an external DAC connected by USB?
On computer you work only with digital signals?



Do you know one of the big advantage of digital signals? The noise imunity. This mean that the signals are not afected by noise up to over 2V for 5V powered circuits. The noise from your power supply are under 100mV for a good power supply (like your Seasonic).
Switching to a linear power supply it is useless. Improving in sound can come only from ground noise that are inserted on external DAC by a SMPS supply comparing to a linear supply.

You need only to use a USB optical isolator. It is more cheap and the improving it is bigger because will reject the noise generated by rest of noise sources from a PC.

Using a USB optical isolator you will not hear any differences between a SMPS and a linear power supply. Or...... you can use a external opticaly isolated DAC.
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Old 26th March 2014, 03:20 PM   #19
BonkM is offline BonkM  Canada
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Quote:
Originally Posted by Julf View Post
Sure - it is your hobby after all, and I guess "if it is worth overdoing, it is worth overdoing" applies.

Looking forward to your results - are you planning on posting any "before" and "after" measurements?
Now you can see what I'm thinking :-P I've definitely gone far past any "normal" approach; absolutely into the "overdoing" zone.

As for measurements, I'd love to. I have no idea how, though :-/ The only thing I guess I could do is take listening notes on a range of tracks on a few separate occasions beforehand, just to establish a sort of baseline. Then take listening notes on the same ones a few times afterward and see if they're the same. Not great, but I'm not sure of another way.

Any suggestions?

Quote:
Originally Posted by sesebe View Post
So, to understood well, you have an external DAC connected by USB?
Yes, this is exactly how I have the system set up. I have a PS-Audio - PerfectWave DAC Mkii, connected via an iFi Micro - iUSB Power. This device provides galvanic isolation.

Quote:
Originally Posted by sesebe View Post
Improving in sound can come only from ground noise that are inserted on external DAC by a SMPS supply comparing to a linear supply.

You need only to use a USB optical isolator. It is more cheap and the improving it is bigger because will reject the noise generated by rest of noise sources from a PC.

Using a USB optical isolator you will not hear any differences between a SMPS and a linear power supply. Or...... you can use a external optically isolated DAC.
Although I can't speak for it as I haven't tried myself, but many who have tried a USB optical isolator (like the Adnaco S3B) have said it's better than a regular motherboard USB connection, but not better than some specialty, linear powered USB cards; most of which cost less than the Adnaco. They claimed a lack of timbre, realism, or nuance to the music, in comparison.

Again, I can't say for myself, but that's the word on the street. Thanks for the heads up, though.

Quote:
Originally Posted by sesebe View Post
This mean that the signals are not affected by noise up to over 2V for 5V powered circuits. The noise from your power supply are under 100mV for a good power supply (like your Seasonic).
Switching to a linear power supply it is useless.
Yes, I understand that this effort may not bear any fruit. I want to try anyway. If I can fit this DIY power supply into the chassis that matches my Audio-PC, then it'll look like a premium component. AND I'll know that I DID IT.

Thank you for the advice, I understand you're trying to save me A LOT of time, trouble, money, and heartache. It's just like I mentioned earlier, though. I've decided to do this and I'm looking for advice how. I hope in the end it makes some difference, but that's not the purpose of this DIY, just a hopeful side-effect :-D
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Old 26th March 2014, 05:32 PM   #20
lexer98 is offline lexer98  Argentina
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Quote:
Originally Posted by BonkM View Post
Funny, right? I suppose I'd compare it to saying, I'd rather stick with just getting punched in the face(onboard mobo switching circuits) then adding getting kicked in the bag(additional switching supply, PICO) as well.



Thank you, Lexer98. I guess I don't know as much as you do about computer electronics and I've used the wrong terms. Please read the following link to see what I'm talking about with the 1.65V going to the RAM.
Audio Asylum Thread Printer

What you will find is that someone has independently powered their RAM via a linear power supply, just like I had said I wanted to do. I am aware that there is no socket (like P24 or P4) to plug this rail into, but I will make it none the less and patch directly into that section of the motherboard, just as the other poster did in the link. Do you understand what I mean now?

Besides that, I have looked on the AMB site at the Sigma11 and Sigma22 threads and will be using 3 Sigma 11's to make the 5V, 3.3V, and 1.65V and then 1 Sigma 22 to make the +/-12V.

The for toroidal transformers for the power, I'm still trying to figure it out, but have so far found something like this:

Transformer #1.
30VCT (15v-0-15v) @ 10A (from Primary)
10V in parallel @ 7A or 5VDC (from Secondary)

Transformer #2.
9V in parallel @ 5A or 3.3VDC (from Primary)
8V in parallel @ 3A or 1.65VDC (from Secondary)

I'm still trying to understand the actual Primary and Secondary output part, but I've contacted a custom toroidal manufacturer and explained what I'm looking for, so hopefully he can correct any misconceptions I have. Feel free to do so here, though, in case you see something out of place.

I really hope I can squeeze all that out of just 2 toroidal transformers, I really don't want to have to use 1 toroidal for each voltage. It would destroy my plan for the case I'm looking at using that comes from the same line as my Audio PC case. It's an extruded aluminum one.
Sorry for answer so rude, sometimes my screws get out ....
Powering the RAM with a linear PSU don't have ANY advantage and don't affect the audio ..... In fact is worse because you lose the BIOS control and complicate the things
The only thing that can affect the audio are the power circuit of the CPU, chokes oscilate at 300-400Khz, but your MB is a really good one, usualy cheapo motherboard or bad designed add noise in the onboard audio or sound card (Some models of EVGA )....



In my opinion don't change anything related with the MB.
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Last edited by lexer98; 26th March 2014 at 05:35 PM.
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