For voltage for testing now I use a Harley Benton PowerPlant.
For the above 9 volts I have a 18-volt transformer and I have built the board of beavis devolt to any voltage between 9 and 18 volts.
I also used this dévolt on some pedals, I have even integrated into a pedal with display.
For knobs that is the uncertain part, I have to take ssay who seemed the most common .............. but it always falls on the case or not you have the right . Those are significant for me that is to be able to switch this or that and see the difference easily on the test bench.
Three legs to see each and I have put 22 potentiometers, its been 66 terminals, that is why I have to opt for the breadboard cut :).
OF aillor to cut and to cut the belt plates (veroboard) I am more hacksaw but at the Proxxon KS Micromot 230Scie table circular.
its working very well it's more clean and precise.
Its costs a hundred euros but if you are the DIY can also be used to cut with details of other materials.
I do not know if what I write will understand because I can not check google translation so if there are inconsistencies forgive me :)