Monday, September 27, 2010

What the Bass Boost Button is actually used for and when you should use it.

We've all seen it, the infamous "Bass Boost" button. It's most prevalent in aftermarket car stereo head units, boom booxes & self powered PA speakers. Sounds fun right? Boost bass, f***ing a! We're all about that these days... right??? (remember though, louder is not better)  I'm about to tell you the actual purpose of the Bass Boost button or switch in some cases, you'll realize why it shouldn't be used all the time and furthermore, why it's specifically designed for certain listening situations based off of the way our brain and ears work together! 

It's purpose all ties into the Fletcher Munson Curve and how the human ear perceives sound.  To give you a real quick run down.  At lower amplitudes(volume) the human ear picks up on mid-range frequencies much better than it responds to low and high frequency information.  This is because we've evolved to hear human speech which lies in the mid-range of the frequency spectrum.  Communication is how we've been able to get to where we are as a species and our ear's perception of sound is just another confirmation of this thought.  Conversely, at high amplitudes, we hear the mid-range with less accuracy.  At high volumes the ear picks up on the low end and high end of the frequency spectrum with much more intensity than at lower volumes.  Long Story short, when it's quiet you don't hear the bass and highs, when it's loud the bass and highs are so loud they drown out the mid-range.  83dB is said to be the ideal monitoring level to take advantage of the most accurate level of our ears perception.  If you can't have a normal conversation over the music it's most likely over 83dB.

Now that we know a little bit more about how our ear's hear we can get back to the Bass Boost button.  It's supposed to be used when you're listening to music at lower volume levels.  Remember from above that at low volume levels we don't hear the low end and high end as well.  When you engage the Bass Boost button on a system it gives a little EQ boost to the low and high end of the material it's processing.  Now you understand why this feature is quite handy when you're playing stuff at a lower level.  Our ears can then perceive a more accurate representation of the original song even when it's quiet.   However, if the switch is engaged at a high volume you're really messing stuff up.  Our ears already hear lows and highs better at screaming loud levels so if you have the Bass Boost button engaged you'll only be adding to the natural problem our ear's posses.

The Bass Boost button is known as many other names such as: contour, boost, hi boost, low boost and probably a billion other clever little marketing names manufactures have came up with.  In the title picture you can see Ampeg has decided to call their system the ultra system and they've given you the option to increase either the highs or lows independently.   Bottom line, look for it, be aware of it, and next time your raging face with your friends slapping beats loud enough to wake the neighbors don't hit that button, you don't need it, your ears are already doing that work for you!


  1. Excellent. Thanks for the info. ;-)

  2. Thanks, It really helped in understanding the audio frequency effect