Hi,
I am looking to build a small arcade unit (so not a bartop unit) using the ControlBlock from Petrockblog. I will need to add a fan. I think I should also add a sound unit or I would be relying on the 3.5mm jack and an amplifier powered from the Controlblock.
Those sound like questions for petrockblock.
Can anyone recommend a fan and a sound unit (HAT) for this? Would I need to add a fan to the box which would be driver from power on the ControlBlock rather than a HAT?
Probably not unless you tell us which model Pi you're planning on using.
I don't know the fitting order of the sound HAT and the ControlBlock.
Neither do we.
General stacking rules are:
- True HATs* cannot be stacked (but see below)
- A HAT+ can be stacked with one true HAT
- A HAT+ can be stacked with one power HAT+
- HAT like boards may be stackable.
If you know which devicetree overlays to load you can disable the HAT EEPROM probe and load them manually which enables stacking subject to the above.
There are third party boards available to allow connection of multiple HAT/HAT like devices without physical stacking. I mention this because petrockblock have chosen to use a 26 pin connector rather than the more normal 40 pin one. Despite the images showing pads on the PCB for all 40 pins.
Sound HATs need the lower 14 pins as well so if you're going to physically stack them the ControlBlock needs to be on top or be modified.
For physically stacking ( as oposed to using a one to many HAT adapter board) the lower board will need an extend/passthrough connector.
Lastly, consider using USB for audio. There are plenty of inexpensive options around. Or use an HDMI screen with built in speakers.
*: True HATs have an EEPROM with ID and config info. All the EEPROMs have the same address.
Statistics: Posted by thagrol — Wed May 06, 2026 11:02 pm
