The Presonus Audiobox has 48V phantom power (and I need it for my condenser mic), the noise frequencies change a bit when I turn the phantom power on/off, but it’s still there.
I just measured the resistance between mains earth of the PSU and the shield of a USB port and the common of the line out on one
of my full sized ATX computers, 0 ohms.
That simplifies things quite a bit.
Does your NUC have bluetooth?
If so, use that as your default audio out, then get the Presonus E4.5.
Not only will you get a bit more low frequency response compared to the E3, but they also have the E4.5 with bluetooth, the E45BT.
It will then also save you on one less cable on your desk. 
You could then use another (quieter) setup for your occasional recordings.
My choice from best to worst would have to be:
Focusrite
Presonus
Behringer
I don’t have specific data on the filtering of either, but I have heard the Focusrite and the Presonus, the Focusrite sounds better to me.
Never been a fan of Behringer.
I have access to a Focusrite, so will record a few seconds of silence do a spectrum analysis and post the results here.
I know someone with a Presonus, will ask them for a few seconds of silence as well.
Mine too, but was lucky, picked up a second hand pair of 1029A’s at a very good price, from a studio that was revamping their kit.
I find their response very neutral with no crazy peaks.
Well, they could still (and probably do) cheat with the filtering.
Consider this scenario…
Simplified block diagram of the average USB audio interface (only input path shown).
The 48V DC generator will most definitely have some kind of filtering, however, they could easily skimp on the
filtering of the DC to supply the actual USB chip.
Ideally, it should be as follows:
The better ones probably include a bifilar choke so that even the 0V/GND will also be filtered to a certain extent.
Yes the NUC has bluetooth.
I once had a (cheap) bluetooth speaker, but my experience with it was so bad that I didn’t consider another bluetooth audio device as a possibility…
The E3.5 also has a BT version now. The E4.5 are a bit too big. So I think I’d rather go with the E3.5 BT.
Bluetooth, means D/A conversion is made inside the Presonus… I have some doubts how good that DAC might be… considering the BT version costs like 20 euros more…
Have to agree, BT can be a bit of a hit or miss affair.
Do you not have a retailer or music store near you that stocks them?
Make a few 320KB/s (CBR) MP3’s of songs that you know well, transfer them onto a small thumb drive and ask them to demo the E35BT
to you using your music.
Done that before, most are very accommodating.
Unfortunately no, I’ll have to order online, but I’ve been searching and I saw good reviews on the BT version of the Presonus.
I don’t have the BT models, so cannot confirm.
However, don’t believe that Presonus would compromise their well known (as respected) brand by trying to save a buck or two on inferior BT modules.
I know there are plenty of diabolical creations like 2.0 BT sound bars and portable BT speakers that are sold to unsuspecting people.
Those sound absolutely horrid, but even there, it’s probably all the downstream crud they use rather than the BT module itself which is 100% digital right up to the analog line outs.
I tried the Presonus Audiobox on a laptop today and there was no hiss, not even when connected to AC.
Must be the NUC then… unfortunately replacing the NUC is not an option right now, so I’ll probably go with the Presonus 3.5 BT monitors for now and possibly buy a focusrite scarlett later.
Thanks for all the input guys!
I’ll come back to report how it went with the BT monitors.
The 48V DC generator will most definitely have some kind of filtering, however, they could easily skimp on the filtering of the DC to supply the actual USB chip.
That would be an interesting battle between engineering and marketing. We’re going to go to the trouble to filter the 48volts only to have the product crash from 5 volt noise.
It’s been our experience on the forum that interfaces that make 48volts are not likely to have frying mosquitoes noises—or at least not prominent ones. USB microphones are almost always the culprit. I used to call the noises “Yeti Curse” from the number of Yeti microphones that arrived with hissing whine.
Koz
That would be an interesting battle between engineering and marketing.
I can tell you that marketing will win 80% of the time, most products are built to a price.
Below, I have attached a silent recording of a few seconds, from a Scarlett 2i2 3rd Gen.
Input is from a Yamaha LS9 and the Scarlett is connected to a Mac-mini (older one, not M1).
Audacity recording level was set to 100%.
It’s extremely clean, very little noise in the very low end.
That’s really silent!
I’ve ordered the Presonus E3.5 BT monitors. Estimated delivery date: next wednesday.
As for recording, I’m not in a hurry, so I might wait a bit longer before ordering an audio interface. I still have some dim hope that I’ll find my ART preamp…
If not, the Focusrite Scarlett Solo looks like a good option.
I’ve got one that I don’t use any more - but I think that you’re a bit too far away to collect it Bruno 
Peter.
Ridiculously so, had to double check that it was in fact working.
If you do decide to go with the Focusrite, maybe the 2i2 is better than the Solo in the long run?
This guy explains the main difference, other than price of course.
And it got way farther after Brexit, even though neither of us moved an inch
Thank you Peter. No worries! Big house cleaning coming soon, so mine might show up eventually inside some box in the garage or something.
Yes, for stereo recording with 2 mics, it is an advantage. Though in the past, when I was using the ART dual preamp, I seldomly connected two mics to it.
If/when I buy it I’ll have to check the prices…
A couple of days ago the Solo was 105 euros and the 2i2 was 168 euros (Amazon Spain).
I was just checked again and the 2i2 just dropped to 136 euros.
Camelcamelcamel is telling me the lowest prices ever on amazon were 82 and 124, respectively. Both prices are from last year, probably from black friday or cyber monday.
I think I’ll keep an eye on both and if I see another sudden price drop I might go for it.
Just a follow-up… Got my Presonus Eris E3.5 BT monitors today.
From my preliminary tests, I can say I’m very happy with them.
Connecting the NUC to them via bluetooth (BT) on Linux was very easy and straightforward (Debian Buster, running i3 window manager, bluez+blueman applet for managing bluetooth connection and pulseaudio control for selecting the output device).
Only negative aspect of the BT connection is the (expected) latency, which seems to be somewhere between 100 and 200 ms.
It can be a bit annoying when watching videos.
If I connect the NUC by cable (audio/headphones out on the NUC to RCA inputs on the monitors) there’s a lot more noise as expected (and very irregular/varying kind of noise), though I need to raise the volume considerable for the noise to be annoyingly noticeable.
The DAC on the Presonus is definitely better than the one on the NUC (also as expected), so despite the latency I prefer to feed the monitors via BT.
I also did a quick comparison between the Presonus Eris E3.5 and the Edifier R1280T speakers which I also have.
Audio source: Marantz CD player connected via RCA cables.
The Edifier have a much stronger bass, but the Presonus have better detail on the mids/treble and also a more frontstage feeling.
For albums which are (too) soft on the bass and too “harsh” on the mids/treble I prefer the “warmer”/laid back sound of the Edifier. The Presonus can sound a bit too aggressive, especially on high pitched voices (and other high pitched “harsh” sounds).
On albums which have a stronger bass component (which was the majority of the ones I listened to), the Edifier are too “bassy” and they kind of muffle the rest. The Presonus will offer better/more pleasant detail here and overall are my favourite.
The E4.5 version of the Presonus would probably have a better bass response (I’m guessing more in line with the Edifier R1280T), but I do not regret buying the E3.5. They’re already wider that what I wished for, anything bigger would take too much space on my desk. I’m not a big fan of punchy basses anyway, so I’m more than happy with the E3.5.
A quick web search and I found out pulseaudio has a latency correction feat. I added +250ms to the latency offset on pulseaudio’s advanced settings for the E3.5BT and now video and audio seem to be in sync!
Well, most of the time… when playing youtube videos on firefox, it takes a few seconds for video/audio to get in sync after I start playing a video or after skipping forward/backward, but it eventually gets in sync.
Playing youtube videos either on chrome or using mpv/youtube-dl also takes a couple of seconds to get in sync in the beginning (feels quicker than on firefox), but skipping forward/backward works fine and doesn’t lose sync.
Playing videos from my disk using mpv player seems to be always in sync from the start and when skipping forward/backward as well.
Glad you are enjoying your Presonus speakers.
As you say, they are not perfect, but have a good performance versus price ratio.
Have you set the EQ/tilt on the back to your preference?
Yes, but I’m actually happy with the neutral position.
I also experimented connecting the Presonus to the (smart) TV in the living room (line out jack from the TV to RCA inputs) and played some youtube music videos from the TV and then compared to playing the same videos via bluetooth from my phone. The difference was huge! I was expecting differences in the DAC on both systems, but I didn’t expect such a huge difference.
My TV also has an optical audio out, so following your previous suggestion, I’m now thinking about buying a small/simple DAC for connecting that optical out to the speakers (Edifier) I have there. The FiiO D3 (D03K) sounds like a good option for under 30 bucks. For that price, I’m not expecting it to be amazin, but it should be a good improvement over the TV’s internal DAC, for a very low cost.
I think you will be pleasantly surprised at the difference between it and the TV’s built in DAC.
Using this exact “no name” unit which I paid like 12 bucks for.
It has optical and coaxial inputs, just using the optical input.
Yes, it was your previous comment that inspired me to get one of this.
I saw “unbranded” ones, selling between 12 and 18 euros, but it’s always a bit of an added risk. You never know exactly what you’re getting… You might be just throwing some money away…
I might be paying an extra for the same hardware, but it’s not a huge difference (well it’s twice as much, but at such low price, twice is not that much, is it?). With the branded one I’m a bit more assured that I get what I’m expecting…
I haven’t ordered it yet, but it’s on my shopping cart 