I have a simple application where I need an SQ S-Link compatible stagebox where I only need to use 1 or 2 outputs. All the options available I’ve seen are way over kill on I/O numbers and price for what’s required. Is there anything smaller, ie 1 to 4 outputs only, or say a 4 inputs, 2 outputs or 2 inputs, 1 output stagebox that doesn’t break the bank?
Smallest device for S-link connectivity and DX protocol is the DX88-P.
https://www.allen-heath.com/hardware/everything-i-o/dx88-p/
AR84 is another option, but it is using the older dSnake protocol.
https://www.allen-heath.com/hardware/everything-i-o/ar84/resources/
In your case, using CatCore (or similar) might also be an option, as it provides four bidirectional (analog) ways.
However, if you also intend to use inputs for dynamic microphones and outputs for high-level line signals simultaneously, you would need to test whether any crosstalk occurs when using simple, inexpensive Cat cables.
(Also, keep in mind that there is only one common ground for all four channels.)
How far are you trying to reach?
A 6 or 8 channel (copper) drop snake with turn-arounds for outs could do.