PAIRING SPEAKERS - WATTAGE VS SENSITIVITY

So you have a shiny new 2x12 Mojotone speaker cabinet, and you have two particular speakers in mind. But how can you be sure if they will play well together?

Besides some very personal opinions on tone, break-up and other variables, there are two major specifications that you should keep in mind when pairing speakers: Wattage and Sensitivity.

Wattage seems pretty straightforward - most of us would think twice about pairing a 25 watt BV-25M speaker with a 70 watt Greyhound speaker, or even a 50 watt Anthem speaker. But what about a 25 watt BV-25M and a 30 watt BV-30H? That is where the subject gets interesting and potentially confusing, but the reality is actually pretty simple.

Electrically, a dual speaker setup will always evenly divide the wattage, with a ceiling based on the rating of the lower-rated speaker. So if you have a 25 watt speaker and a 60 watt speaker paired in a cabinet, you have a cabinet that can handle a total of 50 watts (25 watts going to each speaker).

The same will happen no matter how powerful the higher-rated speaker is, so a 200 watt speaker paired with a 25 watt speaker would not be able to handle a 100W amplifier without blowing the lower-rated speaker. This also applies to any cabinet with multiple speakers, whether it be 2,3,4 or more. The lowest-wattage speaker will always dictate what the entire speaker setup can handle.

Sensitivity (or Efficiency) can be a bit more difficult to wrap your head around, because of the way it is measured and displayed. To measure a speaker's sensitivity, we give the speaker 1 watt of power, and measure the Sound Pressure Level (SPL) in decibels (dB) from exactly 1 meter away. (This is typically performed in a flat-response, non-echoing chamber or room.) This measurement lets us know how loud the speaker will get with a particular amount of power, otherwise known as sensitivity or efficiency.

It seems intuitive that a more sensitive speaker will sound louder than a less sensitive one, but it is the amount of difference that often surprises people. A rule of thumb in the industry is that a speaker's required power doubles with every 3dB decrease in sensitivity (or halves with every 3dB increase). Let that sink in for a second: a speaker with a sensitivity of 100dB will therefore sound twice as loud as one with 97db sensitivity, even if they are rated for the same wattage. This is why it is typically best to pair your speakers so that they are within 3db's sensitivity of each other, to avoid one overpowering the other(s).

For this reason, all of our 12" British Vintage and Anthem speakers have sensitivities between 97-99dB, so that they will all play well together depending on the wattage needed. Our Greyhound speakers are a louder 101.3dB, which pairs well with both our Anthem 12" and our BV-30V at 99dB.

Hopefully you understand a little bit more about the ratings listed on speakers, and how to match them with each other. There is a world of speakers out there to fall in love with, and now you are armed with the right information to find your best sound and love your tone!