The Importance Of Impedance
Electrical
impedance can be a tricky subject to understand if a) you are not very tech
savvy or b) it is explained in too technical a fashion. The following article will attempt to put an
easy spin on electrical impedance and help you understand why it is important
when it comes to selecting certain components for your setup.
In
order to avoid confusion, we are only going to go so deep here. So, in simplest terms, you can think of
impedance as resistance. Where a
resistor creates “resistance” to the flow of a current, it is not the only
electrical component that causes resistance to happen. Think of “impedance” as the overall
resistance of ALL the components in a given circuit.
One
other thing to remember is that impedance is measured in a time-varying and
voltage-varying audio signal. If you
have ever hooked up a multimeter to your speaker leads to confirm the impedance
of the speaker and seen a funny looking number, the above is the reason why. Your multimeter is applying a fixed voltage
to the lead in an effort to measure it, which is why your reading doesn’t
simply come across as a straightforward “8 ohms.”
In the amp world,
most people are typically concerned with impedance as it pertains to
speaker/amp pairings. This is a valid
concern as a mismatch could mean certain detriment to your amplifier over
time. In general, it is always best to
ensure that your amp’s impedance matches that of your speaker : 8 ohms with 8
ohms, 16 ohms with 16 ohms, so on and so forth.
In the short term, if for any reason you have to have a mismatched load,
this is okay and it may simply drive your tubes harder. In the long run however, it is highly
recommended that you have a matched pairing, otherwise you could cause legitimate
damage to your output section in one way or another.
There are a ton of
informative articles out there regarding impedance, what it is, how it works,
and the every little detail you may need to know about it. For those who, want to dig deeper, the world
is your oyster. But for those who simply
need to know what is safe and what is not, you’re a seasoned veteran now!