Super Simple theory on speaker cables


Let's call this ESST for "Erik's super simple theory" of speaker cables and how they actually work.

As you may know, I've been involved in the DIY speaker building hobby for a while, and ages ago got to sit in on a class at Georgia Tech.

Since then I have noticed a weird effect. A slight change in impedance in the 100 Hz to 1kHz range Say, between 3.5 Ohms and 3 can cause a noticeable and unexpected change. In one case, I worked on a Focal which had a really wonky crossover. After analysis, it seemed it was deliberately trying to lower the impedance in the bottom of this range. Lots of resistors that did not need to be there.

So, here is what I think is going on:

Speakers and amplifiers are much more sensitive to impedance changes than we think they are. Yes, of course this should be covered in damping factor and amplifier output impedance, but what if it isn't? What if either the ear is more sensitive, or if there's something else in amps that makes them perform worse than their damping factor?

If this hypothesis is right, then speaker cables need add just a little inductance or capacitance to make a difference.

No quantum, wave theory or skin effect needs to be involved.
erik_squires
What was the configuration of the resistors (series, parallel, combo)?
What were the values?
Did you measure frequency response with & without?


Hey Rocknss
If you are truly interested in the details of the Focal, read here:

https://pqltd.blogspot.com/2016/01/focal-profile-918-ultimate-upgrade-guide.html

This is not my only data point however. I’ve also seen beginner DIY’ers alter the bass crossover by changing the second pole cap, which changed the ESR but only slightly, and found it sounded significantly different. Increasing the series resistor by maybe 0.5 Ohms fixed the issue.


This is not proof, but it's interesting. Like the doctor who first noticed smokers and lung cancer seemed related.


Best,

E
@Erik Interesting, thanks for sharing.
I’ll have to check my cables characteristics! Empirically, I find that slightly capacitive ICs seem to perform slightly better — by which I mean a better sense of clarity & air, i.e. clearer stronger upper mids (& frequencies over 13kHz).

Unless of course, in the case of amps, it comes down to slew arte?