For anyone interested in this, the proaudio overlay has been removed from gentoo's overlay list, which means it's no longer available through layman and no longer mirrored on github.
It's been removed because it had too many (quality) issues which weren't getting fixed.
We (currently 5 people, see https://github.com/orgs/gentoo-audio/people) decided to start a new overlay and add/pull in only packages that we use and can maintain. So far it's still pretty empty, so don't expect it to be a replacement for the proaudio overlay at this point in time, but we're working hard at adding more stuff. Though we do want to guarantee quality to prevent the issues the proaudio overlay had.
This is our current list of things to do https://github.com/gentoo-audio/audio-overlay/issues
It's not in layman yet, but will be once we create the PR to add it to the list, I'd expect that we do so next week once we have a couple of useful packages.
If anyone wants to help out and add/maintain a package that would be great. Feel free to either let us know here or join #proaudio-overlay on freenode.
Gentoo Studio is a source-based Linux audio production system based on Gentoo Linux, for people who want a Linux audio system optimized for their specific computer hardware.
Gentoo Studio consists of three install choices: minimal, basic and complete. A minimal install provides an audio-ready base system with no desktop environment and only basic JACK control software. A basic install provides no desktop environment, but includes basic software to start recording and editing audio and MIDI. A complete install contains Xfce4, a variety of audio and MIDI software, and an array of plugins.
You want a basic audio-ready system with nothing installed because you want to set things up in a very specific way. Minimal is for you.
You want to choose a desktop environment other than Xfce4 but otherwise want a basic audio-ready system with basic audio and MIDI software installed. You will choose your own sets of plugins. Basic is for you.
You want to install a full-fledged audio-ready system complete with an Xfce4 desktop environment. Complete is for you.
I am officially declaring Gentoo Studio to be out of beta. For the most part, it installs well either manually or using the install script, and all of the components that make Gentoo Studio Gentoo Studio actually work.
As usual, please continue to let me know if you have any issues, and I will do the best I can to help.