Linear PSU for USB devices advise needed

Audio Gear Talk
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Just took a OWC Thunterbolt hub out of my Audiorack that I used to power all my USB devices (Rasberry Pi4, waxwing phono stage , Realiable Turntable Light).

But I noticed noise from the Hub itself and especially when the Raspberry pi4 was connected it got especially Loud and the pi also started to make noise.

Connected everything to a PowerBank for now :slight_smile:

But I’m looking for Linear PSUs, that I could use to Power all my USB devices. If possible I would like to avoid spending lots of money on it and have the option to connect multiple devices to one unit.

Also don’t want a phone charger type of thing.

Sometimes next year I will replace the Raspberry pi 4 with a Teac NT507T. So I would need something for my usb light and the waxwing phono stage :slight_smile:

Thanks!

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You may not need a linear supply, but just better SMPSs, like the medical-grade ones from Meanwell or CUI, which I’ve had good results with.

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That might work :slight_smile: but that problem with the hub I mentioned caused me such headaches and annoyed the crap out of me that I took it and did throw it away. At least in my listening room I want to reduce SMPS as much as possible.

In the bedroom I have a mix of gan chargers , apple phone chargers and anker stuff. I hear the crap whining when I get close to them. Even without a load on them.

I hear anker powerbanks whining when I put my ear to them.

This made me even considering I might have tinnitus. But I always wondered why I noticed it worse in the living room and a bit less in the bedroom.

And when I unplugged the raspberry pi4 from the hub it got better, unplugged the hub and zero noise . That’s when I noticed the noise from the charger stuff in the bedroom.

This is my personal preference now :slight_smile: but if possible I will try to get a LPS for the low powered stuff and might consider really good SMPS like Ifi x power for router things .

I did also invest into Supra lorad power cords and will keep adding optical internet over time.

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I don’t know under what conditions an SMPS would whine, but that’s not my experience, with chargers, let alone medical-grade SMPSs. I’d check first whether your SMPSs are overloaded, or whether your AC power has some problem. BTW, LPS transformers can hum if there’s enough DC offset in the AC source, which is not uncommon and it’s why DC offset blockers like this are a thing.

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I have one of those that I use on a may kte and serene kte. I was getting a hum from both units… it was very little but it was there.

I think someone mentioned something about dc offset causing the transformer to run hotter which causes it to draw more power which then generates more heat. :exploding_head:

I don’t how much cooler they are running, the may gets quite warm, but I don’t notice the hum anymore. I’m skeptical about a lot of these power strip claims but this one did help in my scenario.

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Im not really looking for DCBlockers

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Unless you have a proper diagnostic for the unusual SMPS whine you reported, you may well have related issues with an LPS. DC offset is a common issue, but there could be other issues such as harmonics.

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Well, it’s not really meant for the application you had it set up in, but it’d do the job.

Personally, with USB devices like a RPi, I think LPS’s won’t add much benefit.

I’d hold off on any power supply purchases until you decide to purchase this Teac device.

I only use this type with my USB devices, and I use the ones from Apple. Noise free and giveS enough juice to my RPi4, which powers my DAC via USB.

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Yeap, a DC blocker will not stop a noisy SMPS as it’s most likely not the cause of a noisy SMPS.

I know, because my main servers SMPS is noisy (but doesn’t affect the output from the RPi4 or other streamers/DACs across the network).

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Look guys.. I never claimed I want a DC Blocker for a SMPS . I also don’t want to power the Teac NT507T with a LPS . (That thing already has a LPS)

I’m looking for a LPS to Power the Waxwing Phono Stage and my USB Turntable light. If i can also power the Raspberry Pi4 for for the time being that’s Great.

I never said I want to improve the performance or soundquality of any of these devices or that I hear noise in the audio signal.

But what I do hear is a whining, high pitched noise from the hub (went to the garbage already) and from phone charger type of stuff and cheap Powerstrip especially the ones with a on and of switch.

I already have a Furman AC210 in front of my Audio gear against over voltage and surges. I have a Ifi DC Blocker+ in front of My Yamaha AS2200 just in case.

If there is nothing like that I will just keep using my PowerBank.

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I use a Shanti which is a dual outlet 5V for my Chord Qutest and a RaspberryPi streamer. It’s relatively cheap and works well. It should work well for your phono amp but I’m not sure what the current draw is with the lamp.

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