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***agent_kith*** · 26-May-2020, 10:37 AM

Aiming towards simplification/automation, I'm looking for ways to use POE to power the Pi4. Not going to use the POE hat as I like my Argon One case. So I found this:

Any of you tried this before? While this says 5V 2.4A, apparently it is capable of doing 3A (15W total).

I'm going to order some and see how it goes. Getting this also to make sure it's really 5 V as I don't have a meter for USB stuffs.

Not entirely sure when I'll get this, as postal system is a wreck these days. But will report back once on what I find out (if I get 'em).

***agent_kith*** · 29-May-2020, 03:59 PM

What's the point of all this you may ask. The Raspberry Pi4 is a great product, it's small, it's compact and really capable as a player. Really a great little device.

But there is a drawback! I only have one problem with RPi4 - static white noise! I am using the official power supply from Raspberry. And boy oh boy I just cannot get rid of the noise.

Whether you're playing music or video, you can hear this hissing (sounds like running tap) in the background. I tried the analog outputs, also USB to my amp. The noise is omni present and I just cannot get rid of that static noise. To be honest it's irritating as hell and driving my insane. Hopefully I can grab a video of this noise later this weekend.

Unfortunately I don't have another 5V3A PSU to power the Pi. This is the reason for this thread, as I want to try and use POE to power the Pi and see if it can get rid of the noise. The network switch is earthed, unlike the Pi PSU (missing an earth pin) so there is a small chance this will work.

Unfortunately it'll probably take a month if not more to arrive due to the pandemic.

So last night, really out of desperation, I searched high and low for my old iFi Purifier... This device is basically a inline filter for USB cable. I'm using a standard printer USB cable for this, so I connect one end of the cable to the Pi, and the other to the Purifier. The Purifier then connects to my amp.

So what happened? The noise is gone straight away. The standard audiophile "Night & Day Difference". It's such a relief, as this was driving me insane for a while now.

There are some people who still think USB is immune from noise. Honestly do not know what planet they live on. More and more high end stuffs comes with SMPS now, apparently they are really really good. I don't know about that, all I can say is Pi PSU is really shit.

***agent_kith*** · 03-Aug-2020, 05:30 PM

It's been a long time. Mainly because I didn't realise there are multiple versions. The first batch I ordered is non-LK, so they can only go to 100 Mbps max.

Make sure you get the LK version, as shown in the first picture. LK = 1 gigabit Without the LK label, the speed is 100 Mbps! And it's really crap. So long story short, buy the LK version.

So far so good speed wise, I'm getting almost full bandwidth here. Will need to order more in.

Code:
[font=Courier New,Courier,monospace]Client connecting to 192.168.101.8, TCP port 5001

TCP window size:  210 KByte (default)

------------------------------------------------------------

[  3] local 192.168.101.62 port 60918 connected with 192.168.101.8 port 5001

[ ID] Interval       Transfer     Bandwidth

[  3]  0.0-10.0 sec  1.09 GBytes   934 Mbits/sec[/font]

Proper audio audition will not happen for a while yet as I need to get in at least 2 more of these splitters. Probably another 2 months?

***agent_kith*** · 19-Aug-2020, 07:53 AM

Things are slowly coming together now. I've ordered another 2x USB-C POE splitters, also retrofitted the 3x non-LK to DC barrel and now powering some random 5V2A devices in the house.
Replacing my main switch to this POE one so I only need to run 1 switch in the cabinet rather than 2.

Got this switch on a deal at e-bay. The price is too good to not take a punt, and I'm glad/happy I managed to steal this at a good price. Purchased last Thus and arrived the next Monday (Melbourne to Perth), not too bad in terms of delivery times.

Ironically, the first purchase that started this all (an Intel i210 SFP network card) is still missing. It's been 85 days now and in 4 days I'm gonna do a dispute and get my refund. :(

Still yet to properly sit down for an audition, but at least I've got rid of 4 random SMPS PSU around the house. The whole house is in a mess right now, switching out a switch is not as clean and neat as I thought!