adding group inserts to a soundcraft mtk 22

[Ashigari]

I recently picked up a Soundcraft Signature MTK 22 which works very well for my needs, only thing I really miss are inserts on the groups. So I was wondering if it would be possible to DIY some inserts there...group outputs (balanced) on TRS jacks are available and there's a switch per group to route the signal to the master bus (and a mono button which can be ignored for my needs).

My idea is to change the connection on the 'master' switch per group so that instead of the group signal an external signal is routed to the master bus - if I wanted to get really fancy the switch could change between bus signal and external signal making it a button to bypass the insert

Does this sound feasible? I assume I need an op-amp per insert return, anything else I should be aware of like how to power it?
I haven't found any documents online showing the inside of the MTK 22 but I assume SMD and cramped board looking at the size of it..

 

[Rocinante]

You might consider just sending the group out to a patchbay and inserting your effects there.  You could build a group insert box as well.

 

[Felipeareas]

I was thinking about adding insert to the channels themselves (not necessarily them all if it's a too difficult thing)

This would allow me to insert outboard FX to separate channels and while sparing the AUX and group outs for more general uses.

I imagine that size is a concern inside the MTK, but maybe a TRS jack (for in and out) would  fit somewhere?

Cheers

 

[abbey road d enfer]

Adding inserts to an existing mixer starts with a schematic diagram, in order to evaluate where in the circuit.
Then you need drawings of the lay-out, in order to locate the components on the PCB.
I suspect it's not modular, probably a large PCB parallel to the front, populated with SMD components that are somewhat more difficult to lift than through-hole.
I coldn't find the service manual on-line...

 

[Felipeareas]

Thanks a lot for the reply,

I was thinking If maybe anyone had opened it before. I imagined the channel circuit would have similarities (if not identical) with some other soudcraft previous consoles..

I don't think they would be interested in making this schematic available soon... But as a very popular console maybe someone will find that out and share with us?