I assembled this post slowly throughout my process, so it's a bit long and not for all you younguns with ADD that are used to 80 character text messages...
I would first like to be a conformist and join the others in complimenting Tim on his excellent kits. I bought a set of 8 preamps around the first of December but didn't get to build them for about 4 weeks. I felt like a little kid with a brand new erector set for Christmas. (Anybody else remember those?) The kits were fun to build and well organized, with any possible pitfalls fully explained in the instructions. I did not have a single missing or incorrect part in the lot. I heard one or two of the pres before I bought them, and they're a welcome addition to my studio.
For those of you who are thinking about these kits, I highly recommend them. They're so well put together that after the first one I stopped checking the BOM (not recommended) and made it a habit to work with a bottle of Bailey's at hand (also not recommended). I took pleasure in dumping all the parts out on the table in a tangled mess (not recommended) and ignoring the instruction booklet as much as possible (also not recommended). Despite my rash behavior all 8 worked perfectly and required no troubleshooting, although I recommend a more measured approach if you're new to circuit building.
This week I built 2 N72s, 2 A12s, and 4 C84s, so I thought I would comment on the difficulty of the builds. My personal opinion is that they are all equally easy. (I could say equally hard, but I'm a glass half full of Bailey's kind of guy.) If you've done something like this before then they won't be any trouble. If you're new to it then it may be a challenge, but these kits are so well put together that I dare say they're a great place to learn. If any of you are interested I put a few photos of my process up on facebook. Search for Musicman Jezza.
These preamps remind me of Heathkit, a company that used to provide simple electronics kits that could teach without demanding too much, while at the same time also providing cost savings on the finished product. Ironically, while the Heathkit market at the time was in amateur and consumer products the only space for this approach these days is in high-end electronics. Tim has found a great little niche. (For those of you that don't know about Heathkit, make it a point to look it up.)
My favorite part of the build: Unwrapping everything just after the UPS guy left
Most annoying part: Those silly little foil stickers on the rotary switches
Easiest part: Finding resistors. Tim ships them taped in order instead of loose.
Hardest part: Completing the project even though the Baileys bottle was empty
Hardest part (seriously): Soldering one particular transformer to the board after I cut the wires too short.
Most exciting part: Adding the pres to my patch bay
Least exciting part: Beginning pre #8. Bored.
A few personal suggestions:
A magnifying glass is NOT an optional tool unless you have the vision of a fighter pilot. I use one of those circle lights with a glass in the center, and I couldn't do good work without it. Tiny iron tip + tiny solder + big magnifying glass = easy clean build.
If you're doing more than one or two preamps then a tap for the XLR connectors is also NOT an optional tool. It will cost you $4 at the hardware store and you'll save more time than the trip took, plus you'll save your screws.
Buy as many or more preamps than you can afford.
Do it right the first time so you don't have to troubleshoot.
Allow cats near the kits at your own risk. Mine were VERY interested in swatting all the tiny little pieces all over the place.
Thanks again Tim. I'm sure I'll keep these for many many years.