When upgrading my crossovers earlier this year it involved a long deep dive into what each part (cap, resistor, inductor) does and how each one affects the sound. Every single one of the parts in there now is the exact same part, as measured the standard way using a meter to measure inductance, resistance, capacitance. Has to be. Otherwise it would screw with the frequency response and mess up the sound of the speakers. The goal is to make it better, not different. Better.
One of the things I had learned a long time ago with another crossover is resistor quality matters. Bad low quality resistor, smeared low quality sound. One way this happens, resistors heat up. When this happens resistance increases. This is just a fact, you could look it up. Hotter the wire, more the resistance.
Why do we use a resistor in a crossover in the first place? Why not just caps and inductors? Because the different drivers have different sensitivity, we use the resistor to match levels. Resistors are how we turn the volume down. Literally. A resistor is an attenuator. There are even volume controls made with a whole bunch of resistors of different values, called stepped attenuators. Each click is a little more or less resistance, a little more or less volume.
So in a speaker it is real important that we use resistors that can handle a lot of power without heating up. Heat is the enemy. To the extent a resistor gets hot it increases resistance, which turns down the volume, and this can happen very fast. Dynamics are fast. Thus a cheap resistor can rob your music of dynamics.
So I selected the very best Path Audio resistors I could find. The result is an already very lively and dynamic speaker became even more impressively dynamic! Details are largely dynamic swings. Also got a nice improvement in detail.
Now to the fuse. Just a thin piece of wire, it is supposed to burn out at a certain point, before too much current passes, in order to prevent the wires inside burning out.
Burn out? Yeah. The fuse filament gets real hot, so hot it burns out.
Shocking! Yeah, no seriously, that’s what it does. Tiny thin little wire, gets real hot, so hot it melts.
Ordinary fuses are designed only to fail, no effort whatsoever goes into trying to get the most linear response possible at all points up to failure. Reasonable then to expect ordinary fuses to get hot a lot, and change resistance a lot, even well before failure. This robs the music of detail and dynamics. Just like the cheap resistors in my crossover.
What are the improvements people hear with better fuses? Great improvement in dynamics and detail. Precisely the same improvements our scientific analysis has led us to expect.
Real scientific analysis, the kind that breaks physical phenomena down into discrete understandable parts, analyzes the function of each part, and then proceeds logically to examine the consequences.
