Here are the pre amps almost finished only this time using DIPs (Dual In-line Package). These are also known as PDIPs and CDIPs with the first capital denoting either plastic or ceramic.
The build was much easier but still not exactly easy. The observant reader will notice that the first op amp stage is not connected to the two stages on the pot. At this point in the construction I do not know exactly how close I can get them so will wait until later.
The switch has silver contacts and is 5 pole 2 way allowing 5 different inputs. I chose this type because of its silver contacts, plastic construction and low contact resistance. The volume potentiometer is a high quality Alps design and has seven wipers to ensure good contact even after lots of use.
Both input switch and potentiometer will be mounted right up against the back wall of the amp to be as close to the inputs as possible. This will reduce signal path lengths and also interference problems. Both shafts will be attached to the front panel knobs via a non-metalic extension.