The Hifi Podcast: What Is Input & Output Impedance?

Wrapping your head around audio circuits can be daunting for non-engineers, but it’s not hopeless. There are many important concepts that anyone can learn to help them become a better audiophile. Sometimes you just need the right context and explanation for it all to start making sense.

From time to time on The Hifi Podcast, the hosts — including our own testing technician, Duncan Taylor — take a deeper dive into topics like these to try to make sense of them.

The topic du jour? Impedance! And not speaker impedance, like you may be thinking. Nope, we're talking about intra-chassis impedance, which may affect sound quality more than you think.

One of the most integral elements of the way two pieces of gear sound when connected together is impedance — input and output impedances of each piece of gear and why and how they react and relate to one another.

After the usual intro segments, the feature portion of this podcast episode has engineer Darren going into detail about why the hifi rule of thumb rings true that you want a high impedance input and low impedance output on nearly every audio device out there.

Just how low, or how high, and why that matters to the sound are explained, and there’s also a quick journey into the impedances of connecting cables and how that affects the components as well.

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