Completed magnet wire interconnects with Eichmann bullets

I have in the past made interconnects with “magnet wire” ¬†– this is a solid copper conductor insulated with a thin layer of enamel, so also search for “enameled copper wire” when looking for it. It is used for making the windings of transformers and motors, and is therefore plentiful and cheap. My earlier efforts involved wrapping magnet wire in a spiral around various type of core, like teflon tubing. But I was never all that happy with them and ended up putting my efforts at the time into the cable recipe devised by Jon Risch, involving the cores of Belden 89259 and 89248 twistedRead More →

For longer runs, or low-level signals, you may prefer a shielded interconnect. Here is a simple “recipe” for making a shielded interconnect. (Its hardly a recipe at all, really, but it’s useful to have something to point people to.) While you can buy your own cables made this way, and of course you’re welcome to, if you’re planning to make anything more elaborate then you should learn how to do one of these. The ingredients: Switchcraft 3502A RCA plugs. These are available from various suppliers including Parts Express ($2 each of you buy ten or more). I read that they are pretty decent for inexpensiveRead More →

I needed to make some more speaker cables recently. Since this was for a 4-way system, cost-effective was a good idea. After thinking through some options, I grabbed a 200 meter roll of CAT-6 network cable on eBay for 50 dollars. By any reasonable method, that is enough copper to make quite a lot of speaker cable! The neat thing about making speaker cables out of network cable is that you can use as many strands as needed to get the gauge you want. And you can trade off inductance against capacitance as well. While there is a popular “recipe” for making speaker cables outRead More →

Box dimension calculator

Here’s a little spreadsheet that helps to figure out the dimensions of a speaker box. What you do is enter a bunch of dimensions, and it tells you the actual internal volume. I’m sure someone must have done this before but I couldn’t find one.¬†Here’s the file: Box dimension calculator Here’s a screenshot: Here’s how to use it. In the Enclosure section, enter the best-guess dimensions, and the thickness of the wall material. In the Round Port section, enter the diameter and length of the port as calculated by your box design program. If it’s a sealed box, enter 0 for the length. If youRead More →