[pioterd]

If the PSU will deliver 5V/1A at 100V, it may actually deliver 2A while running on 230V

Thank you. What about iPower2 then? Can it deliver more than 4A while running on 230V?

 

[Thorsten Loesch]

Thank you. What about iPower2 then? Can it deliver more than 4A while running on 230V?

Probably, on peaks. I still found adding super capacitors improved the available power on difficult to drive headphones.

I have an electronic load here, if I have time I will test.

Thor

 

[farits]

Moondrop Venus, 100db 18 ohm. When connecting a linear power supply to Zen can from AliExpress, it adds bass, but the sound becomes harsh. With ipower2, there is less bass, but the sound is smooth and pleasant))

 

[Thorsten Loesch]

Moondrop Venus, 100db 18 ohm. When connecting a linear power supply to Zen can from AliExpress, it adds bass, but the sound becomes harsh. With ipower2, there is less bass, but the sound is smooth and pleasant))

Interesting. That you perceive more bass may be down to more available power.

I am somewhat surprised that there is a material difference in higher frequencies. The incoming voltage is chopped up by a 1.2MHz switching frequency regulator that turns 5V into +/- 12V.This is a looped regulator.

If it is possible to try, let's isolate causes. Could you plug in the iPower in addition to the linear power supply and take a small wire to make a connection between the barrels of the DC connectors (iPower ground to Linear Power ground). See if there is a change in sound with and without this connection.

Also, what is the rest of the system?

Thor

 

[farits]

Maybe. I listened for a month with a 5V 4A linear power supply.
Yesterday I decided to try iPower2, the sound became gentle, soft, it sounds open, airy, I listened for hours and didn’t get tired of the sound. Unexpectedly strange.
Connected Zen DAC Signature V2, iPower X power supply; Zen Can Signature power supply iPower2, I liked such a gentle sound

If it is possible to try, let's isolate causes. Could you plug in the iPower in addition to the linear power supply and take a small wire to make a connection between the barrels of the DC connectors (iPower ground to Linear Power ground). See if there is a change in sound with and without this connection.

Became interesting. I don’t quite understand English, should I connect the plug itself?

 

[Thorsten Loesch]

Became interesting. I don’t quite understand English, should I connect the plug itself?

Uhgggg.... A little hard to explain.

What is your source for Zen DAC and how is it powered? Does it have a Earth connection?

Thor

 

[cubemacplayer]

Buying this one, wish me luck, not the best but hey

From a review:
I ordered this power supply to power my Wemos. The voltage is around 5.2V which is completely within limits because the voltage drops slightly under load but the 5V is maintained. I am also happy with the cable length and am overall happy with the purchase of this power supply.

Amazon Link

 

[pioterd]

For similar price you can find this one 5V/6A:

https://www.meanwell-web.com/en-gb/ac-dc-medical-desktop-adaptor-with-3-pin-iec320-gsm60a05--p1j

 

[cubemacplayer]

For similar price you can find this one 5V/6A:

https://www.meanwell-web.com/en-gb/ac-dc-medical-desktop-adaptor-with-3-pin-iec320-gsm60a05--p1j

I found it here. Well, this one might be better being medical grade - idk what it means but it should be more reliable.

 

[Meridian7]

I found it here. Well, this one might be better being medical grade - idk what it means but it should be more reliable

https://www.cybernetman.com/blog/medical-grade/

A google hit fwiw.

 

[Thorsten Loesch]

Well, this one might be better being medical grade - idk what it means

The main difference between generic ITE and Medical is that medical needs to have less leakage current from main allowed, than ITE versions (0.1mA for medical, 0.25mA for ITE).

Please remember that generic SMPS are not designed for low noise.

Generally agency compliance takes front seat.

So they will be rather noisy at very low load, so called green mode, which causes high levels of audio noise. This is needed to meet current legistlation that requires < 0.3VA standby power.

And at high load, because common design is for ~100mV Peak-Peak switching noise at rated current. Depending on the precise design switching frequency is variable and can be within the audio range at full load (this improves efficiency which is now mandated at >= 80% for a 15VA external PSU) or is fixed frequency at 67kHz or 132kHz.

EMC and leakage/touch current are the other Agency requirements that inform power supply design.

While now technically illegal (as they can never meet efficiency and standby regulation requirements), linear power supplies are free from all these various problems, toch/mains leakage current tends to be very low. EMC is a non issue, so no measures for that to make performance worse. The output noise is what it is, using LM317/LT1085 type 3-Pin regulators can give a reasonably low noise.

This is why I usually recommend linear supplies over switching supplies. They are easier to "get right" for audio.

Thor

 

[pioterd]

100mV Peak-Peak switching noise

That meanwell 5V/6A medical PSUs have in general lower ripple and noise measured parameter than non-medical. If the spec allows maximum value of 120mV p-p, it is measured at around 60-70mV level (ripple and noise measured at 20MHz by using 12” twisted pair terminated with 0.1uF and 47uF capacitor ). Audible noise, for me possible to detect only at +18dB gain level over 12oclock (which I don’t use) is lower than stock ZenCan 5V/2.4A PSU, but definitely higher than iPower2 (which brings no noise at all I’d say). I use non-medical 5V6A meanwell and I’m happy with it

 

[Thorsten Loesch]

That meanwell 5V/6A medical PSUs have in general lower ripple and noise measured parameter than non-medical. If the spec allows maximum value of 120mV p-p, it is measured at around 60-70mV level (ripple and noise measured at 20MHz by using 12” twisted pair terminated with 0.1uF and 47uF capacitor ).

That's a lot. A simple linear PSU with a generic 3-Pin Regulator, even a fake one will normally have much lower noise.

Audible noise, for me possible to detect only at +18dB gain level over 12oclock (which I don’t use) is lower than stock ZenCan 5V/2.4A PSU, but definitely higher than iPower2 (which brings no noise at all I’d say). I use non-medical 5V6A meanwell and I’m happy with it

The Zen CAN, as mentioned, is fairly resilient to noise. I would expect PSU noise to be completely eliminated, what you hear likely relates to the EMC measures, more specifically the so-called "Y" Capacitor.

The main claims to fame of the iFi iPower(s) in the later versions is first of all < 100uV noise at half load WITHOUT the ANC system and the Transformer construction that minimises noise coupling and allows the Y-Capacitor to be minimised (It can actually be removed completely and still pass EMC testing). As such it is very similar to a good linear PSU.

Thor

 

[cubemacplayer]

I'm with my new 5.1v 4A from amazon and I can't say I can hear a difference with my headphones - HD800S, HD650, Focal Clear MG, Ananda and have not tried Sundara. But I'll kep it for piece of mind. I honestly think I won't hear a difference chasing a linear power supply so I won't chase this dragon. Maybe the device is running hotter? Well I don't know the ZenCan was never cold

But as a sidenote, @Thorsten Loesch I'm really enjoying the ZenCan and specially the ZenDac - it's hard to find a dac like that. Both sounds amazing an the combo can power basically anything. I know the price point aspect of it but even then I don't think that a higher price point it's a bad buy either. I think when comparing to what's around, considering features, design, SOUND, reliability and post-service, it's truly an unique device. My 2 cents really as a consumer.

 

[Thorsten Loesch]

I'm with my new 5.1v 4A from amazon and I can't say I can hear a difference with my headphones - HD800S, HD650, Focal Clear MG, Ananda and have not tried Sundara.

The first three should be fine, no matter.

The Hifiman are also fairly sensitive, at ~ 110dB/1V (Ananda) or 107dB/1V (Sundara), though impedance is at the lower end of the spectrum with 33 Ohm or 39 Ohm. Especially if using Bass Boost and Crossfeed the limitations may show up.

Where people observed issues were with DCA models with ~ 105dB/1V & 12 Ohm impedance and especially on the Balanced connection, or something like the Expanse with 99dB/1V and 26 Ohm impedance.

But I'll kep it for piece of mind. I honestly think I won't hear a difference chasing a linear power supply so I won't chase this dragon.

Linear PSU's often have lower Leakage capacitance. If this causes differences depends on system context.

My 2 cents really as a consumer.

Thank you for the flowers.

Thor