Fosi's New Linear Power Supply

[mhardy6647]

What exactly do you mean by wonderful?

and my variant on the question, FWIW:

What exactly do you mean by wonderful as expected?

What did you expect, @RScheckmate?
I.e., what is different -- the strong implication here* is that the initial state was sub-wonderful, somehow elevated to wonderfulness by the substitution of a LPS for a SMPS.

This is ASR -- I would expect a finding of wonderful as expected to return an error:

_________________
* or at least my strong inference here.

 

[Ruediger]

Didn't we just learn from the AHB2 teardown that we DON'T want a linear power supply anywhere near our amp stages?

scnr not 100% serious

 

[Ropeburn]

and my variant on the question, FWIW:

What did you expect, @RScheckmate?
I.e., what is different -- the strong implication here* is that the initial state was sub-wonderful, somehow elevated to wonderfulness by the substitution of a LPS for a SMPS.

This is ASR -- I would expect a finding of wonderful as expected to return an error:

View attachment 545362
_________________
* or at least my strong inference here.

Did you mean: *interference

 

[TonyJZX]

i dont think this is the worst thing in the world... if you are immersed into the Fosi extended universe then you might have a pair of V3s and one of their DACs... and that's three psus already and so for $200 to have a row of neat boxes...

and i do get you can just buy a lab power supply and kludge up the cables but 99% of people arent about that life

 

[RandomEar]

i dont think this is the worst thing in the world... if you are immersed into the Fosi extended universe then you might have a pair of V3s and one of their DACs... and that's three psus already and so for $200 to have a row of neat boxes...

and i do get you can just buy a lab power supply and kludge up the cables but 99% of people arent about that life

This supply doesn't work with the V3 Monos. Not the right voltage by quite a margin. It's exclusively for low voltage stuff (5-15 V) meaning DACs, streamers and the occasional low power USB device.

 

[atothek]

Received mine.
Since X5 Phono requires 16V, it can't be connected to the PSU, right?

 

[solderdude]

Received mine.
Since X5 Phono requires 16V, it can't be connected to the PSU, right?

No indeed it can't.
The X5 phono requires 16V AC
The linear power supply only provides DC
Not to worry though as the X5 phono already has a linear power supply in it (if that floats your boat).

 

[Richard G]

£240 for a 40W PSU (@5, 12 or 15V) ? They're having a laugh

Two main outputs have switchable watts. … pardon me for not getting the joke but what is funny? Are you referring to the price? See my next post.

 

[Richard G]

RME did it too

~ Broadly ~ similar … and at USD 1300 > six times the price

 

[Redacted]

Two main outputs have switchable watts. … pardon me for not getting the joke but what is funny? Are you referring to the price? See my next post.

Err, the price?
.

 

[Richard G]

As it’s just 1/6 of the price of the RME, you must find the RME price has you rolling on the floor with laughter

 

[MAB]

As it’s just 1/6 of the price of the RME, you must find the RME price has you rolling on the floor with laughter

The fact that 200-300 is still a lot of monies, especially for something that doesn't make one iota of sound difference. And doesn't even work with all of Fosi's various gear, X5 Phono for example. I hope the person asking earlier didn't buy it to find it isn't compatible.

The thing is, this hobby could be cheap if so many companies weren't out to sell stuff people don't need, isn't an upgrade, and is just more stuff to break.

 

[mhardy6647]

A thought:
selling a gratuitous LPS for a product that doesn't need it doesn't strike me as all that different than Ford selling a pickup truck, the Raptor R, with a 720 hp (537 kW) supercharged 5.2 L V8. I do not think that carpenters, painters, and weekend garden center visitors need quite that much headroom (to use an audio term!), even if they pull a trailer.

https://www.ford.com/trucks/f150/models/raptor/

 

[atothek]

I got it for 175 eur and can connect 3 devices - that‘s pretty fine for me.

 

[Waveform Fidelity]

All this discussion about "black backgrounds" from LPSU's brings me back to the talk I am going to deliver in a couple of weeks to the local audio club. This is my slide about how the noise floor of the listening room affects the listening experience. The noise floor of a "dirty" vs. "clean" PSU is about 100dB below the signal at least. The elephant is literally in the room, and they are ignoring it whilst worrying about miniscule effects.

View attachment 542623

That talk will be fun. I wonder how many of them will get angry at me or agree with me.

Doesn’t this thing have a cheapo fan that will get noisier as time goes on? My guess the acoustic noise will be in the pink region

 

[RScheckmate]

Doesn’t this thing have a cheapo fan that will get noisier as time goes on? My guess the acoustic noise will be in the pink region

negative Sir Fidelity ...
arbitrary random comments like this are useless if based on speculation and false information

to help...I measured it while running and warmed up (15 and 12 V outputs being used at the time )
1) The fan in my PSU20 does not register with a radio shack sound level meter on lowest setting (C weighting 60db range so should see -10db so less than 50 db).
2) using the "Sound Meter" app on my android placed within an inch of the device, then clicked power off ... showed no change. This linear power supply was super quiet near 39 db which matches the basis specs that their specialized fan operates near a lowly 30db (in my case, my normal quiet room was higher)

I do hear (barely) the most quitest of whisper of a fan, only if I place my ear directly on the side of the power supply.
I suspect this fan and cooling will be influenced by your room temp and airflow but to me there is zero issue.
This will be "silent" in all normal situations .
I just checked and turned supply upside for a while and watched fan again ... it isn't moving after half an hour of playing in a 21C deg room

I continue to enjoy the cleaner wiring setup I now have with having one normal plug leaving my desktop area vs 3 power cables to bricks and wallwarts.
My system looks great which was a prime reason/drive in my use case.

My planar Fosi i5 headphones sound great and my near field Totem Loon speakers within 3 feet of my ears is superb (60-90 db listening levels).

Having opened and worked on power supplies in some Dac's like the Fosi R2R BR15 that can manage externally fed DC or direct AC current, and looking at their circuitry, though as good as their components and design are for the money, an external DC linear power source with torriodal power to spare is better step towards clean power from whatever AC source your city has for the Dac's and streamers to do their thing.

 

[egellings]

Fosi is peddling nonsense in their marketing;

View attachment 542215

So is it black, clean or both at once?


JSmith

It's pretty easy to get solid, quiet DC out of a presumably regulated linear power supply. No point in bragging about it.

 

[DonH56]

Fosi is peddling nonsense in their marketing;

View attachment 542215

So is it black, clean or both at once?


JSmith

LOL. What most fail to realize is that "linear" supplies have rectifiers (diodes) to convert AC to DC and those diodes are both nonlinear and generate large switching spikes, much like switching power supplies. The difference is the fundamental starts at the power line frequency, or more usually twice the power line frequency, so the noise lands right in the audio band. Switching supplies operate well (often a decade or more) above the audio band and so the switching noise is way above our hearing. The biggest problem with switching supplies and noise IME is poor RFI rejection on the part of other components that allows the noise into the circuit. No matter the supply, proper decoupling, shielding, and attention to layout is critical for low noise.

 

[RScheckmate]

I hear you.
so good design, not just type of power supplies helps with low noise...got it.

I just blew a capacitor on a Fiio BR15 R2R dac I have with a bone head move I did on plugging the wrong supply line (18V vs 12) . I fixed the single blown capacitor and all is great a day later but inside I saw some shielding around the very simplistic AC power components (top and bottom of board. Even they took a stance on this isolation.

some say no to any power supply helping audio potential but context is important because that statement appears false given your insights

I may open my PSU20 to inspect design for this before people jump too far with no facts. (i undid screws but it wasn't obvious how to get inside so I stopped..high Voltage caps need careful understanding) .
I think I recall Gabster testing this in youtube so I may need to revisit his video to get a how to...and get my own data for this.

 

[antcollinet]

some say no to any power supply helping audio potential but contect is important because that statement appears false given your insights

Or not.


This is typically said because devices with the stock PSU typically measure with inaudible noise and distortion. It doesn't matter how much you improve the PSU - it cant get more inaudible.

It is possible (though unlikely) on the other hand to mess things up by changing the PSU such that there is something audible going on.