About 80% finished:
The ZIF socket does not fit into DIP socket holes, it needs larger holes, so i soldered it "on top" like a SMD part...
Further it seems i forgot to order some parts, so its back to order more parts...
Search online for "Classic 47 Headphone" and you will find kit´s to solder that are basically cmoy headphone amplifiers.
As im still waiting for the PCB´s i soldered up such a kit to give it a go:
Both Op Amp´s are already in sockets and its delivered with a set of NE5532.
So far i have given it a quick test to confirm it works, and then tried to hear a difference against OPA604 and AD8065. But i cannot say that its a clear difference...
While waiting for the PCB let´s use KiCad´s 3D view to show how the ZIF socket will look when mounted:
The ZIF socket is stacked in the DIL socket´s, i placed some resistors too close so on this version of the PCB its not possible to solder the ZIF socket directly... This will be fixed once i have build up the first amp and therefore discovered the other hidden bugs still inside...
It´s possible to use Dual or Single Op Amp´s, but dont use both at the same time, or maybe give that a try?
A 28 pin ZIF socket is used, that gives 1 row spacing between the Single and Dual Op Amp´s.
(the ZIF is not needed, inserting the Op Amp´s directly into the DIL sockets is ok. but it will not look as fancy...)
The Parts arrived, this is a bag full of Op-Amp´s and everything else needed for the build up.
The red item in the lower left corner is a DIL ZIF socket, with above some SOIC ZIF sockets. Like this its possible to test different OP Amp´s without soldering them in, or lets say thats the plan :-)