This was my rather utilitarian project, to house four Volumio+Hifiberry Amp systems in as compact a headless rack as possible, which lives in the plantroom of my house driving ceiling speakers in four rooms.
I don’t have the tools or skills to fabricate these things from scratch so it’s all off-the-shelf components - 1U rack for four rPi 3B systems, 1U rackmountable 8-port ethernet switch, 1U 6-gang surge-protected PDU, all housed in a vertical 4U wallmounted rack cabinet along with the power supplies.
The Hifiberry is an Amp2 on three of the rPis but the fourth one is an Amp100 as it drives a stereo pair of ceiling speakers in the living room (the others only drive a single stereo ceiling speaker in the office and bathrooms). There was a bit of surgery needed to fit that fourth one onto the Pi rack - the amp is bigger which meant it had to go on upside down compared to the others, with slightly different sized connector slots needing to be hacksawed into the rack.
Everything “just” fits - you can close the door and forget about it, if everything is working! Access to pull out the microSD for reflashing is fine with the Amp2 systems but the hat has to be lifted off to get to the card on the Amp100 system (tbh that is a problem with the amp design rather than this particular cabinet or rack). Attaching hdmi and USB cables in order to connect screens and keyboards whenever troubleshooting is needed is very fiddly.
Oversall I’m quite happy with it. It lives in a cramped plantroom with the boiler, solar inverter, ASHP controls, MVHR, water filters, electric meter etc. so it needed to be as compact as possible. If I were starting again and had space I’d maybe go for a slightly taller cabinet - this one is 400 high - just to make it easier to get the power supplies in, and give a bit more space at the top for access to the ethernet cables. A pdu with individual on/off switches for each socket would also be nice, so the systems could be restarted without pulling the little power plugs out of the amp boards.
Hope this is useful to some of you - even if only to inspire you to make something prettier!
The following photos were taken when the project was being put together:
