Fact or Fiction: All Same-Size Speakers In a Rig

[StickBass]

I've heard it stated as a fact of physics that all speakers in a rig should be the same size (i.e., all 10's, all 12's, OR all 15's, not a mix) or else there are negative phase cancellation effects leading to inferior sound. And yet some of the top boutique speaker companies produce cabs with multiple sizes of driver, claiming they are the ultimate one-cab solution.

I have often mixed speaker sizes in my stack rigs over the years. For years I ran 410 + 118. My new rig is 210 + 115, and I'm loving it. Why would that be inferior (or less efficient, or whatever) to a 410, 610, 412, or 215?

Is it truly "bad" to use multiple speaker sizes within a single rig?

[FF Petro]

Absolutely not. Look at the fEarful cabinets that are so highly regarded here on TB. They are a 3 way cabinet (3 different speakers) and are said to have an unusually robust sound.

In an underengineered cabinet using different drivers can cause all sorts or issues. If the cabinet is well designed with appropriate drivers, box and crossovers than the different drivers help to recreate the frequencies of your bass by working together.

Using different drivers can open up problems and the simplest way to create more sound is to add more of the same speakers but that doesn't mean it is the only way.

[tekdiver500ft]

In a properly designed cab different size speakers is fine. I think where people get confused is when people tell them not to mix speaker size in multiple cabs, such as a 115 and a 410 together. This can cause problems.

[Jeff Scott]

Originally Posted by FF Petro

If the cabinet is well designed with appropriate drivers, box and crossovers...

+1

This is the key issue, multiple size drivers are fine as long as properly designed crossovers are used to divide up the frequency range and send them to the appropriate driver(s) in the complete system.

[fdeck]

At low frequencies, the frequency- and phase-response curves of a speaker are joined at the hip. Thus if two speakers have different frequency response curves, they will also have different phase response, resulting in some phase cancellation.

Problem? Let your ears be the judge.

[JimmyM]

Originally Posted by StickBass

I've heard it stated as a fact of physics that all speakers in a rig should be the same size (i.e., all 10's, all 12's, OR all 15's, not a mix) or else there are negative phase cancellation effects leading to inferior sound. And yet some of the top boutique speaker companies produce cabs with multiple sizes of driver, claiming they are the ultimate one-cab solution.

Some are, some aren't. Cabs like the fEarful or the Audiokinesis Thunderchild are designed to take good advantage of different size drivers with crossovers and mid drivers and stuff. However, there are a LOT of boutique companies that simply put full range drivers of different sizes in a single box and call it good. Bass players do a lot of engineering by looks, and they see a big speaker and a small speaker and they think that the big speaker is for lows and the little ones are for highs and mids when they're both working full-range and overlapping each other. But that's what they want, and many cab companies are more than happy to throw together some crap to satisfy them. And that's where possible phase issues come into play.

[bassmasta_01]

Originally Posted by JimmyM

Some are, some aren't. Cabs like the fEarful or the Audiokinesis Thunderchild are designed to take good advantage of different size drivers with crossovers and mid drivers and stuff. However, there are a LOT of boutique companies that simply put full range drivers of different sizes in a single box and call it good. Bass players do a lot of engineering by looks, and they see a big speaker and a small speaker and they think that the big speaker is for lows and the little ones are for highs and mids when they're both working full-range and overlapping each other. But that's what they want, and many cab companies are more than happy to throw together some crap to satisfy them. And that's where possible phase issues come into play.

+1

[GizmoTheOne]

^
+100

[Spectrum]

LOL When I first saw the title to this thread I thought it said,

"Fact or Fiction: All Same-Size Sneakers In a Gig"

Wouldn't that hurt your feet?

[billfitzmaurice]

Originally Posted by StickBass

And yet some of the top boutique speaker companies produce cabs with multiple sizes of driver, claiming they are the ultimate one-cab solution.

If the drivers operate in separate bandwidths via use of a crossover then using different driver sizes for those bandwidths may indicate a well engineered system. If there is no crossover it's voodoo.