Question A quiet, futureproof PSU for gaming/music production PC

Sep 1, 2021

I'm on a quest to optimize my PC to be thermally efficient yet quiet on demand, as I use it for both gaming and music production. I recently rebuilt my system in the be quiet! Silent Base 802 and I'm very happy with the result, as noise levels went down and thermals improved, even when using the closed, sound dampening panels.
But this is just the starting point. Now when the constant loud noise from my old case fans is gone, I'm looking to replace my old Corsair TX650 power supply as it makes a constant buzzing noise at around 300 Hz and it's driving me crazy, especially when I do audio work and keep the case fans at minimum so that they're practically unaudible.
This is also a good chance to futureproof my PSU so I'm willing to go for 750 or maybe even 850 watts, even though it could be a bit overkill for my current setup. I'm also looking for modular options only.

I'm torn between several brands & models.

-Corsair RM750x & RM850x (2018): The 2018 models seem to have the best combination of quality, low noise and affordable price. But they have in-cable capacitors and it's my understanding that it could be troublesome when routing the cables from behind the motherboard.
-be quiet! Straight Power 11 Gold: As I've fallen in love with my new case and the Pure Wings 2 case fans, I'm tempted to buy more stuff from be quiet. But the review on this series was not flattering. Is it worth the risk or will I have a fried PSU or components in a year or two?
-Seasonic Focus GX-850: On sale for just 99,90€, so it's a tempting offer. Almost suspiciously tempting. The noise level is also a mystery. How loud is it?
-Fractal Design Ion Gold: They say it's optimized for quiet performance but me and Fractal definitely have a disagreement on what is "quiet", at least based on my old case fans. The flat cables look really neat though.
-The absolutely highest-end models like be quiet! Dark Power 12 and Seasonic Prime Titanium: I might be able to afford either by saving up for a couple of months. But are they really worth it? I've also read about some strange fan noise issues in the Primes.

Any experiences with these PSU models and product ranges would be greatly appreciated, especially regarding noise & reliability.
Note that I'm not going for a 100% silent build. I'm going for a system that can be sufficiently quiet when needed as to not disturb any music-making or other audio work. A slight hum is ok. Harmonic droning or buzzing and high-pitched glitchy noises are not.

System specs if needed:
ASUS Z170-A motherboard
Intel i5-6600K w/ Cooler Master Hyper TX3 EVO (looking to replace this with a suitable Noctua cooler)
MSI GTX 980 Ti 6 Gb gaming edition
2 x 8 Gb Kingston HyperX DDR4 2400 MHz
Three Samsung SSDs
4x Pure Wings 2 140mm case fans (3 intakes, 1 exhaust)
1x Noctua NF-A14 FLX 140mm case fan w/ LNA (top exhaust)
Noise measured from where I'm sitting is about 39 dB average in idle when the case fans are set to lowest RPM. Most (or all) of it comes from the CPU cooler & PSU. Measured with an iPhone app, so not a scientific reading.