Floor Coupling: Why Getting Your Bass Cabinet Off the Floor May Help Your Tone

If you’re a bass player who rolls a heavy speaker cabinet to the gig, and once the cab is on the stage, you turn the cab on its side, or remove pop-out casters. This could be just what you have always done, or it could be to make the cab sit onstage with more stability (ever played on a slanted or uneven stage?)

However, once your bass cab is on the stage, there is one good reason to keep the casters on -- to avoid a condition called floor coupling. When you place your bass cab directly on the floor, the sound from your cab will be transferred directly to the floor, thereby increasing the overall boominess and bass response. The floor essentially becomes an extension speaker reflecting your sound.

At first glance, this may seem like a good thing. Who wouldn’t want more bass response? While it certainly may work for some people and in some locations, as having an amp coupled directly to the floor often makes your bass tone feel more powerful --  in the context of a live performance, decoupling your rig by getting it even a few inches off the floor provides many benefits.

1. A more controllable bottom end. A main drawback of floor coupling is that it is very hard to control and inconsistent from place to place. This is due to the coupling’s dependence on the flooring material and covering, location to the walls, and where you are standing in relation to your amp. By isolating your amp from the floor, you can increase the consistency, and make more precise adjustments using your bass amp’s EQ section. It’s much easier to coax more bass from your amplifier by turning a knob than relying on the surface your amp is on to deliver it. Creating a more consistent low end from place to place reduces the distraction of your tone changing at each gig.
2. Increased midrange presence and definition. While stage-filling low end is essential, the bass guitar’s midrange is what is discerned through the mix by both audience and band members. If your amp is coupled to the floor, the potentially excessive muddiness has the tendency to rob the midrange definition from your sound, making your bass vanish in the mix and filling the stage with a whole lot of boom and not much punch.
3. Lower stage volume. Keeping stage volume as low as possible can work wonders for your live show. Getting your amp off the floor not only reduces the mud, but moves the amp closer to ear level, making it easier for you to hear yourself. Oftentimes players will turn their amp up much more than it should be, due to improper EQ, a muddy sound caused by coupling, or the amp sitting so low on the floor that all the sound is blowing past their legs. The combination of decreased bass and higher placement makes it so you don’t need to turn your amp up to obnoxious, room clearing levels to hear yourself.

Aside from using casters or a dolly board, you can also eliminate the floor coupling effect by using an amp stand or your milk crate of cables. Anything that creates space between your amp and the floor will work just fine. Stacking multiple cabinets instead of placing them side by side can lower the coupling footprint to the floor, and it increases the height to hear yourself.

There are some players who enjoy the increased bass response that coupling provides, and have learned to EQ their amp to adjust for it. There is no right or wrong way, as long as you are getting the sound you want. Understanding floor coupling is important for those who want to avoid its unwanted effects.

Do you keep your amp on the floor or raise it up? Let us know in the comments!

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