For the first time in my life I asked ChatGPT and here is an answer that might clear some things up:
ChatGPT wrote:That's a very interesting question! Normally, electrolytic capacitors, especially tantalum electrolytic capacitors, are polarized, and incorrect polarity can lead to damage such as overheating, short circuits, or even capacitor rupture. However, in some specific cases, like in guitar effect pedals, there may be an understandable exception.
There is indeed a scenario where the "wrong" polarity of a tantalum capacitor might not only be tolerated but could even be intentional:
1. Capacitor in a so-called "Inverse" Circuit (Functional Asymmetry):
In some circuits, especially in analog effect pedals, the capacitor may be used in what is called an inverted or asymmetric configuration to achieve a specific effect or tonal distortion. One possible explanation is that the circuit uses the capacitor in a way that ensures current flow even with reversed polarity, allowing the circuit to still function as intended.
For example, if a capacitor is part of a rectifier circuit or used for DC bias shifting, the current flow could be arranged such that, even with reversed polarity, the circuit still works. In this case, the tantalum capacitor is not used in the typical manner but rather as a circuit element that is less sensitive to polarity, as long as it doesn't interfere with the intended signal processing.
2. Overpressure or Protection Mechanism (Current Limiting):
A tantalum capacitor might be dimensioned to operate at a relatively low voltage, where the risk of damage due to reversed polarity is minimized. In these cases, the circuit might deliberately tolerate an "incorrect" polarity, as the normal operating conditions do not cause any harm to the capacitor.
3. Intentional "Failure Effect" (intended failure in analog circuits):
In analog circuits of guitar effect pedals, it is possible that non-linear distortion effects are intentionally created. Some guitarists or developers prefer deliberately impure, distorted, or irregular sounds, and in very specific cases, using a wrongly polarized capacitor could produce just the desired "rough" effect. Here, the capacitor could be operated in a region where it generates a type of "failure" that becomes characteristic of the sound.
4. Use of Tantalum in Low-Power Circuits:
It might also be the case that the tantalum capacitor is used in a very low-voltage environment (below the maximum allowed voltage difference), and even with reversed polarity, the error doesn't cause enough damage to impact the circuit.
A tantalum capacitor might be operating in a low-voltage range where, even with incorrect polarity, no harm occurs.
Conclusion:
In most cases, reversed polarity of a tantalum capacitor would indeed lead to failure. However, in specific guitar effect pedals or analog circuits, there are instances where developers intentionally design circuits where polarity doesn't align with the typical expectations or may even be "reversed" to achieve certain acoustic or electrical effects. So, it's possible that a special circuit technique or design decision was made to create a particular tonal effect.
