I have them, but only for personal use for device modification. How many do you need?
Best Regards,
Aleš
Hi derekr,
thank you for letting me know.
For DAM1121 you can use dual board, which you can check it here: Ultra low noise hifi power supply TPS7A4700, DIY preamplfier, DAC, headphone amp | eBay.
For Raspberry PI and similar SBC media players I designed 6x LT3045 parallel power supply which will provide 3A. If everything goes ok I will have them ready in a week or two, but only a few PCBs. Stock for these chips is little low now at distributors.
Best Regards,
Aleš
Hi Aleš,
Do you have a link for me? And do you have some measurements like ripple/noise of this board?
I'm very interested if it outperform my 5A lm338 design with your pcb you send me. The LT3045 have nice specs compared to the LM338.
The lm338 i use for rpi, works like a charm (not cheap if you want it perform good).
Hi folks.
As much as I like Ales regs, I have to admit I replaced the Meanwell-Ales combo
with an iFi iPower for powering the Pi. ( My PI runs in the range of 350-600mA)
I also added a reservoir cap to the iFi. And also cut the iFi cables.
My PI has an Allo Kali and a DAC stacked on top. Both HATs are powered separately.
My audio performance went up up with the iPower in place. There haven't been a night and day difference. It's been sufficient though to leave the iPower in place.
The iPower offers 2.5A btw !?!?
I'm really wondering what am I looking at here. What's causing the difference!?!?
As a primary reg Ales reg still feeds my Sabre DAC with 3.6V.
I'm more than happy with the reg at that position.
But on the Pi (mainly running as a pre-reg for 3.3V/1.8V) it's not my first choice.
Any ideas to improve the situation are appreciated.
Thx
As much as I like Ales regs, I have to admit I replaced the Meanwell-Ales combo
with an iFi iPower for powering the Pi. ( My PI runs in the range of 350-600mA)
I also added a reservoir cap to the iFi. And also cut the iFi cables.
My PI has an Allo Kali and a DAC stacked on top. Both HATs are powered separately.
My audio performance went up up with the iPower in place. There haven't been a night and day difference. It's been sufficient though to leave the iPower in place.
The iPower offers 2.5A btw !?!?
I'm really wondering what am I looking at here. What's causing the difference!?!?
As a primary reg Ales reg still feeds my Sabre DAC with 3.6V.
I'm more than happy with the reg at that position.
But on the Pi (mainly running as a pre-reg for 3.3V/1.8V) it's not my first choice.
Any ideas to improve the situation are appreciated.
Thx
You could try:
- powering the regs with a linear PSU
- powering the regs with a battery
- using a small isolation transformer with the linear PSU
If you want to try a linear PS, a good place to start would be jean-paul's LT1764A-based regulator -
http://www.diyaudio.com/forums/group-buys/264185-squeezebox-touch-psu.html
http://www.diyaudio.com/forums/group-buys/264185-squeezebox-touch-psu.html
TPS7A4700, still the best for the Touch.
If you want realy better use a battery powered (lipo) reg like the TPS above.
Hi.
I'm also running the Ales reg with LiFePO4 (2*3).
And I do have several linears over here too.
Linears are out of scope.
LiFePo4s charging = too much hassle.
The iPower is a switching supply btw. And I wouldn't replace it with any linear supply
I have at hand.
My goal would be to beat that iFi device @ <$50 .
But that would require the localization of a potential issue
with my Meanwell-Ales combo first.
E.g.
1. Lower power headroom (1A vs. 2.5A)
2. Poorer mains filtering
3. Lack of power reservoir capacity
4. EMI/RFI
5. ESR
6. Overregulation ( 1 stage is usually better than two)
7. ?
One more:
The Uptone LPS1 uses superregs as power-reservoir with the same reg. btw. According to a fellow inmate that would
beat the iFi iPower. But with the LPS1 comes e.g. option 5 and "8" into play: the grounding scheme.
Cheers
I'm also running the Ales reg with LiFePO4 (2*3).
And I do have several linears over here too.
Linears are out of scope.
LiFePo4s charging = too much hassle.
The iPower is a switching supply btw. And I wouldn't replace it with any linear supply
I have at hand.
My goal would be to beat that iFi device @ <$50 .
But that would require the localization of a potential issue
with my Meanwell-Ales combo first.
E.g.
1. Lower power headroom (1A vs. 2.5A)
2. Poorer mains filtering
3. Lack of power reservoir capacity
4. EMI/RFI
5. ESR
6. Overregulation ( 1 stage is usually better than two)
7. ?
One more:
The Uptone LPS1 uses superregs as power-reservoir with the same reg. btw. According to a fellow inmate that would
beat the iFi iPower. But with the LPS1 comes e.g. option 5 and "8" into play: the grounding scheme.
Cheers
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I measured the ifi which has a much higher noisefloor then the TPS linear PS.
Ifi measures behind a isolation transformer and i measure 'without' and also at the end of the dc cable (real life situations) with some load.
I think that makes the differences between my values and ifi.
When it comes to 'earth' it is also strange that the ifi smps hasn't a earth.
As it comes to price, the ifi is unbeatable. A good TPS system cost +4x the ifi.
Ifi measures behind a isolation transformer and i measure 'without' and also at the end of the dc cable (real life situations) with some load.
I think that makes the differences between my values and ifi.
When it comes to 'earth' it is also strange that the ifi smps hasn't a earth.
As it comes to price, the ifi is unbeatable. A good TPS system cost +4x the ifi.
Not yet, but I can send you one for inspection
Expected output noise is around 0.33uV, this is calculated using equation from LT3045 datasheet page 26. @soundcheck
Which Meanwell are you using and which regulator? Meanwell RS-15-5 and TPS7A4700?
making something similar to ifi Ipower under 50$ will be really challenging.
Just sent you an email today if you could measure my PSU. After that I read this post. I hope you have time to measure it.
@KingPin
Measuring noise at these levels is an art on its own.
The question to me is - what actually makes the difference?
I mean, there are tons of measures on the way to get the noise
even further down. It might not even be the noise level, after all,
causing the difference.
@Ales
Yep. It's been a RS-15-5 and TPS7A4700 combo.
IMO the challenge is to understand what really makes the difference.
Perhaps taking the 5V from a "properly modified" Meanwell might
do the trick already. (Never actually tried that)
Especially if that 5V is used as pre-regulated voltage only.
Another thought.
The PI has a 3.3V and a 1.8V regulation onboard.
Replacing these to end up with a single stage regulation on each rail
might be another option. If it's worth it !?!? Hmmh.
I could imagine though, that if the PI-I2S bus and clocks are better powered this way,
there might be a difference.
Measuring noise at these levels is an art on its own.
The question to me is - what actually makes the difference?
I mean, there are tons of measures on the way to get the noise
even further down. It might not even be the noise level, after all,
causing the difference.
@Ales
Yep. It's been a RS-15-5 and TPS7A4700 combo.
IMO the challenge is to understand what really makes the difference.
Perhaps taking the 5V from a "properly modified" Meanwell might
do the trick already. (Never actually tried that)
Especially if that 5V is used as pre-regulated voltage only.
Another thought.
The PI has a 3.3V and a 1.8V regulation onboard.
Replacing these to end up with a single stage regulation on each rail
might be another option. If it's worth it !?!? Hmmh.
I could imagine though, that if the PI-I2S bus and clocks are better powered this way,
there might be a difference.
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A SMPS will have more Leakage Currents and noise re-injected into the mains than a good Linear.
Leakage Currents are missing in your list above (there are other things missing as well).
One weak spot in your arrangement above is the Meanwell.
The LPS-1 reduces the Leakage Currents to nearly nothing.
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So true.
This is how i measure:
An externally hosted image should be here but it was not working when we last tested it.
At the end of the dc cable i put a load and put the probe-tip as seen above in picture 3 to give you a reallife situation.
I can measure at max around ~500nV ripple / -131dB.
At least it gives you a clear image how the LPS will perform against others.
But indeed it's better to use a isolation transformer and put some bnc connectors on it right after the regulator caps.
I do have issues with iFi too.
ifi claims to be 20 times better on the noise front (1uV vs 20uV) than a LPS - "in the audio band".
And then they exclude mains frequencies and switching frequency (<30uV!!!) from that statement. All that is nothing but a bad joke.
What LPS do they use for comparison!??!
That kind of marketing sucks.
However. Under real life conditions that device IMO performs quite well.
"An SMPS have more leakage current..."
I'd guess the amount very much depends on the SMPS of choice??
Since there is no protective ground on the iPower, that leakage current argument gets shunted to ground. But perhaps the lack of it makes the difference.
The Meanwell with 80mV p2p to start with is obviously out of range.
Here the question is how Ales reg copes with this.
I mean Ales is making promises about the noise level after the reg.
Who'd bother what's going on in front of it !?!?
I had the Meanwell connected to protective ground btw.
The Meanwell medical grade SMPS RPS-60-5 might be the better choice
here.
ifi claims to be 20 times better on the noise front (1uV vs 20uV) than a LPS - "in the audio band".
And then they exclude mains frequencies and switching frequency (<30uV!!!) from that statement. All that is nothing but a bad joke.
What LPS do they use for comparison!??!
That kind of marketing sucks.
However. Under real life conditions that device IMO performs quite well.
"An SMPS have more leakage current..."
I'd guess the amount very much depends on the SMPS of choice??
Since there is no protective ground on the iPower, that leakage current argument gets shunted to ground. But perhaps the lack of it makes the difference.
The Meanwell with 80mV p2p to start with is obviously out of range.
Here the question is how Ales reg copes with this.
I mean Ales is making promises about the noise level after the reg.
Who'd bother what's going on in front of it !?!?
I had the Meanwell connected to protective ground btw.
The Meanwell medical grade SMPS RPS-60-5 might be the better choice
here.
Specs looks really good Ales, when you finished with your project i would be happy to buy one, let me know.Not yet, but I can send you one for inspection
Not really, it's a general thing.
Bear in mind though that there appears to be two types of Leakage Current, one is quite well known and characterised for a single device, and the other one is less so and only has meaning for two or more devices used together.
I'd be weary of some assumptions here, because there could still be other issues, some aided by the interconnects. Additionally, if that same 'ground' is somehow connected to some signal reference, you could get other types of problems.
The Meanwell with 80mV p2p to start with is obviously out of range.
Here the question is how Ales reg copes with this.
I mean Ales is making promises about the noise level after the reg.
Who'd bother what's going on in front of it !?!?
This doesn't cover the two other types of noise that can flow through the mains, one of which definitely also flows in interconnects.
It might be better in terms of single-device rated Leakage Current, but it most probably won't be in terms of how the other types of 'leakage current' are, which occur by virtue of interaction between two or more power supplies, aided by interconnects.
It might still not be as good as a good Linear or as a battery, despite battery having its own noise profile and despite Linears having their own Leakage Currents (generally lower than SMPS).
If you have the opportunity of doing several tests of different configurations, you will be able to select what sounds better in your rig.
The Raspi has a recurring flaw in the combined Ethernet/USB controller or interface which can restrict abilities, especially with high rates (like DSD). I'm not sure they resolved it in newer designs.