Key to Crossover Diagrams
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Crossover schematics and wire colors provided are taken from whatever original documents are available to me, or from actual speakers.

Note! What is actually in your speakers may vary from the schematics published here.

Symbol	Description	Comments
	Driver (woofer, tweeter, etc.)	These are the actual parts that produce the sound. Note that passive radiators do not appear in the schematic since they are not wired.
	Capacitor	Value given in microfarads. Rated for at least 50, but usually 100 volts. Non polar electrolytics are typical in EPI and Genesis speakers. Capacitance values add up when they are used in parallel, and are lower, according to a complex formula [(C1*C2)/(C1+C2)], when wired in series.
	Air Core Choke	Value given in millihenries, followed by the specified wire gauge, if available. Although this is not always done, choke coils should be mounted with their axes at ninety degrees to any others that are within six inches or so of them.
	Iron Core Choke	Value given in millihenries, followed by the specified wire gauge, if available. "Cored" choke coils, which look a lot like transformers (but with only two lead wires), can achieve a much higher inductance for a given number of wire turns, which lowers costs and series resistance. Unfortunately, they also exhibit saturation at a lower power level.
	Resistor	Value in ohms/power rating in watts. The non inductive type should be used. Mounting position should take heat dissipation into account.
	2 position switch	It was the height of fashion in the 70's to provide switches (and potentiometers, below) to allow "frequency contouring" to the owner's taste, or to compensate for room acoustics. In my opinion, these should be set to "normal," or bypassed (see below). This is the flat setting, the way the speakers were designed to sound.
	3 position switch
	Potentiometer (a/k/a rheostat, or L-pad)	Potentiometers (usually wire wound, high power types) were sometimes used as simple variable resistors, that is, only the center and one side connection were used. They are prone to corrosion on the "wiper" and the resistive element, resulting in poor signal transfer and "crackling" sounds when adjusted.
When bypassing potentiometer or resistive adjustment systems with fixed, soldered parts, if the "normal" position is indicated to be somewhere in the middle, or keeps some of the resistors in the circuit, a network of equivalent power resistors should be soldered into the crossover in their place.
	Wire and color codes	In cases where the wire color code is known to me I have colored the appropriate part of the circuit diagram to represent this information. Most original wiring in affordable speakers is a bit thin. Replacement with at least 16 AWG is highly recommmended.
	Junctions	At this point I have not used visible dots to indicate the places where 3 wires meet and are connected to each other, as is standard in schematics. Crossovers tend to have a fairly simple circuit topology though, making it easy to draw them with no "crossing" of current tracks. Thus, everywhere that the lines of a diagram meet, there is actually a connection.