[dougms3]

Thank you.
Me too, actually I’m using a 12vdc 3A power supply. But, it’s a switching power.
Switching power supplies are known to produce electrical noise, which I’m trying to swipe off all around my system.

If I don’t misunderstand,
the linear power supplies are the old fashion coil transformer ones, and seem to be a great option against noise.

In order to power my headphones amp, I was thinking of a linear power supply, in fact this made me remember that maybe, I already have one, in my APC power backup.
This thing is soooo heavy, there is massive coil inside that would make this job, both ways. From 110vac to 12vdc, and 12vdc to 110vac.

Which lead me to this idea, why not vamping the 12vdc at the battery connection..???

However, my worry was… when the back charge the battery , wouldn’t it apply a slightly higher voltage to it? Like 14V or so…?

Which could be harmful to the amp.!!! Maybe.
If the amp does not possess any regulator!!!?!?

Finally, I wondering if I can’t add to the backup a DC-DC stabilizer 9v-30v to 12v…???
Like the one used in automotive application.

What would you think???

I think it might be easier and more cost effective if you got an lps.

Aliexpress alot of options under $100 or beatechnik has the lhy audio lps for a bit more.

I have the ifi i power x on my p20 and it's a huge upgrade from the stock ps but a lps does improve it a little further.

I use the a sengterbelle toroidal core lps but if i could go back I'd opt for the rcore version.

 

[saebasan]

Thank you for your return of experience.

In 2019, I bought the P20 for 82 bucks.
Ifi linear power supplies ain’t cheap at all. ($85 for 12v/1.8A, $330 for 12v/4A… hum hum hum )
As for « no brand » linear psu, we can find some 12v/5A for $92.
Which looks more affordable to me but still more expensive than the amp itself, so still expensive to me eyes.

I already have a big « coil » in my backup psu, for $0.
Adding dc-dc stabilizer 9~36v to 12v, would cost $12 to ensure a « strict 12v » coming out from this psu.
Furthermore, the amp will be « protected » by this regulator/ stabilizer, which is a nice function of this solution to consider as well.

As for me, this mod (repurpose of a backup psu to a linear psu) is a challenge/try that would cost only $12…
(Which is 8 times less expensive than a « no name » solution,
27 times less expensive than a ifi solution… for something like 12v/5A.)

So, when you say « cost effective »… maybe we don’t have the same meaning standards.
When you say « easy », yeah , your are right
I’m maybe reinventing the wheel , and risking a little bit….

Finally, if it doesn’t work well, if the sound doesn’t pop well, if it turns dull or worse than what I have now, then, I can still buy a no name linear psu for $92, I would have spent $12 for nothing (or feeding my experiences curiosity at least… and I could give you a report here ) Total $104

Thank you dougms3 for your though.

 

[saebasan]

I think it might be easier and more cost effective if you got an lps.

Aliexpress alot of options under $100 or beatechnik has the lhy audio lps for a bit more.

I have the ifi i power x on my p20 and it's a huge upgrade from the stock ps but a lps does improve it a little further.

I use the a sengterbelle toroidal core lps but if i could go back I'd opt for the rcore version.

Btw, this is a good occasion to see you folks, how do you pair this P20 with a psu…

Maybe we can list here what psu we use…?

 

[dougms3]

Thank you for your return of experience.

In 2019, I bought the P20 for 82 bucks.
Ifi linear power supplies ain’t cheap at all. ($85 for 12v/1.8A, $330 for 12v/4A… hum hum hum )
As for « no brand » linear psu, we can find some 12v/5A for $92.
Which looks more affordable to me but still more expensive than the amp itself, so still expensive to me eyes.

I already have a big « coil » in my backup psu, for $0.
Adding dc-dc stabilizer 9~36v to 12v, would cost $12 to ensure a « strict 12v » coming out from this psu.
Furthermore, the amp will be « protected » by this regulator/ stabilizer, which is a nice function of this solution to consider as well.

As for me, this mod (repurpose of a backup psu to a linear psu) is a challenge/try that would cost only $12…
(Which is 8 times less expensive than a « no name » solution,
27 times less expensive than a ifi solution… for something like 12v/5A.)

So, when you say « cost effective »… maybe we don’t have the same meaning standards.
When you say « easy », yeah , your are right
I’m maybe reinventing the wheel , and risking a little bit….

Finally, if it doesn’t work well, if the sound doesn’t pop well, if it turns dull or worse than what I have now, then, I can still buy a no name linear psu for $92, I would have spent $12 for nothing (or feeding my experiences curiosity at least… and I could give you a report here ) Total $104

Thank you dougms3 for your though.

Yeah its a very inexpensive amp, I paid $60 for mine used.

Upgraded the caps and added the ifi ipower x which cost much more than the amp itself but I feel like its worth it since its a very capable amp and excellent price to performance.

I use it preamped with my audio-gd master 19.

If you can build a cheaper power supply, go for it but I think the LPS will yield better results even if it does cost a good bit more. I think an LPS under $100 is a good deal, as I said I have the sengterbelle lps and it outperformed the ifi ipowerx by a small margin.

https://www.aliexpress.us/item/3256...1987!sh&gatewayAdapt=glo2usa&_randl_shipto=US

 

[saebasan]

Yeah its a very inexpensive amp, I paid $60 for mine used.

Upgraded the caps and added the ifi ipower x which cost much more than the amp itself but I feel like its worth it since its a very capable amp and excellent price to performance.

I use it preamped with my audio-gd master 19.

If you can build a cheaper power supply, go for it but I think the LPS will yield better results even if it does cost a good bit more. I think an LPS under $100 is a good deal, as I said I have the sengterbelle lps and it outperformed the ifi ipowerx by a small margin.

https://www.aliexpress.us/item/3256801804146613.html?spm=a2g0o.store_pc_groupList.8148356.57.57d12cd8MJQXrZ&pdp_npi=2@dis!USD!US $88.00!US $88.00!!!!!@210318d116808405699495338e9cc6!12000018336051987!sh&gatewayAdapt=glo2usa&_randl_shipto=US

Sengterbelle seems to be a very nice hifi shop on that platform.
Their stuffs looks legit.
Your linear psu costs $130 with shipping to the states. For 12v/4A. It looks very well designed

 

[Arum16]

Thank you.
Me too, actually I’m using a 12vdc 3A power supply. But, it’s a switching power.
Switching power supplies are known to produce electrical noise, which I’m trying to swipe off all around my system.

If I don’t misunderstand,
the linear power supplies are the old fashion coil transformer ones, and seem to be a great option against noise.

In order to power my headphones amp, I was thinking of a linear power supply, in fact this made me remember that maybe, I already have one, in my APC power backup.
This thing is soooo heavy, there is massive coil inside that would make this job, both ways. From 110vac to 12vdc, and 12vdc to 110vac.

Which lead me to this idea, why not vamping the 12vdc at the battery connection..???

However, my worry was… when the back charge the battery , wouldn’t it apply a slightly higher voltage to it? Like 14V or so…?

Which could be harmful to the amp.!!! Maybe.
If the amp does not possess any regulator!!!?!?

Finally, I wondering if I can’t add to the backup a DC-DC stabilizer 9v-30v to 12v…???
Like the one used in automotive application.

What would you think???

On my P20, I'm using a swiched PSU, 12vdv 6A.
Fortunately I have no noise complaints. Even considering my complete rig (desktop, displays, DAC and the P20) are powered from the same wall power outlet.

About your other questions, there are other members on this thread more knowledgeable. Let's wait they chip in and answer your questions

 

[DBaldock9]

For a "budget" brand name 12VDC 3A - 6A linear power supply, you might check out the Pyramid models that are available on Amazon, and some other shops.

 

[saebasan]

For a "budget" brand name 12VDC 3A - 6A linear power supply, you might check out the Pyramid models that are available on Amazon, and some other shops.

Thank you.

If you’re lucky enough to live in the states, it seems to be a super deal.
Can’t find it in Japan, nor Aliexpress thought.

Actually, as for you, are you using a Pyramid psu with your P20? In that case, which model?

 

[DBaldock9]

I'm using an older, Radio Shack 12V 3A linear power supply, that I originally bought to use with a flatbed scanner that someone gave to me in the '90s.
Since then, I bought a new scanner, that has a power supply - so the old one was available to be used with the P20.

 

[saebasan]

I'm using an older, Radio Shack 12V 3A linear power supply, that I originally bought to use with a flatbed scanner that someone gave to me in the '90s.
Since then, I bought a new scanner, that has a power supply - so the old one was available to be used with the P20.

Oh, I see.
It seems these power supplies come from the radio world. Ham, walkie-talkie, etc…

May I ask then? When we do a research for these power supply in 12VDC, the results give us power supplies that actually output 13.8VDC. (we can see that in the spec sheets too)

Would it mean that the voltage you’re actually using in the P20 is 13.8VDC?

If so, what is our P20 amp tolerance in terms of input voltage???

 

[DBaldock9]

My P20 has been operating OK, while using the power supply that I've got.
I did put some Cary Gold Plated 9-Pin Tube Sockets/Risers under the tubes.
https://www.amazon.com/gp/product/B00KOTBMMM/
With the tubes lifted up out of the case - it means that the amp runs cooler than it did originally.
.

 

[saebasan]

My P20 has been operating OK, while using the power supply that I've got.
https://www.amazon.com/gp/product/B00KOTBMMM/

So, it is not a strict obligation to use 12vdc.

It can be a little more.
I wonder how much? What’s the tolerance?

Someone knows????

 

[Arum16]

So, it is not a strict obligation to use 12vdc.

It can be a little more.
I wonder how much? What’s the tolerance?

Someone knows????

Theoretically if a circuit is designed to work at a given voltage (the P20 at 12vdc), you should supply it with that voltage value, with the least variation possible.
The more stable your PSU is, the better. Current might vary during circuit operation (more so in the transient phase of switching power on, till it stabilizes).

Over-voltage is never a good thing. It should be considered a hazardous condition.
This is like overclocking a CPU, or over-pressuring an air system or a hydraulic one.

 

[saebasan]

Yes, but variations are normal things that obviously happen in the real world.
By design, for any system, always some acceptable deviation is calculated, ex. 12V±0.5, 12V±1, 12V±2,… ?

The specifications are not really precise, at least for what I can find.

Maybe, no one knows it.

 

[ShaolinGrump]