Graphic EQ build notes:

1. There are only two types of parts to attach: Sliders and Sockets.
2. First, position the sliders. They have 4 pins on one end, 2 pins on the other, so it's impossible
   to get them the wrong way around. Carefully straighten the pins a little if they don't fit into
   the holes. I find it easier to insert the 2 pin side first, then slide the 4 pins into place.
3. Position all the sliders before starting to solder, making sure they're completely even and flat.
4. Soldering the sliders is simple, but this is a dense board, and you are soldering on the same
   side as the small surface mount components. In a few places - for example close to the
   unpopulated C32 - it is very tight. Be careful not to connect the empty solder pads of C32
   to the pins, as this will cause strangeness.
5. When soldering the sliders, all the pins should the same length; if you see some that are a bit
   short, check they're properly pushed through. Otherwise the solders won't be flat and even.
6. Check all the slider joints - if you miss a connection you can get weird intermittent issues
   that are hard to debug.
7. Once the sliders are done, put the sockets in place, then put the front panel on. Ensure the
   Input socket is at the bottom and the output socket is at the top. Loosely tighten the bolts
   and make sure it all looks right before soldering the three points on the back of each socket.