Get these articles in our

6 comments / Posted by Bruce Ohms


Bass Amp with Contour Knob

In addition to your amplifier’s standard EQ controls, a contour knob, like the one found on many Carvin Audio bass amplifier heads, can further help you find a bass tone that sits perfectly in your band’s mix. While the function and engineering of each given contour knob may vary, the general purpose is to provide an extra tool for tone shaping the midrange frequencies and providing a classic “scooped mids” sound.

Scooped Mids: the Basics

Scooping out the mids is exactly what it sounds like- removing midrange content from your signal at specific frequencies. This practice tends to get a bad reputation for being detrimental to your bass tone, and it is understandable- with the cymbals and guitars occupying the high end, and the kick drum competing with it to hold down the low end, a bass guitar’s midrange is what makes it cut through the mix.

So why would you want to scoop the mids? Many players enjoy dialing in this sound because it accentuates the low end thump and high end attack of the bass and removes some of the clutter and nasally sound of the midrange. This tends to be a great option for slap styles, heavier rock, and players who want their tone to sit a particular way in the mix. Surprisingly a subtle mid scoop plays very well in mellower rock music. It defines the low mid and low note groves without providing extra note noise that mix with the cleaner guitar tones.

Enter the Contour Knob

With a contour control, it is possible to change the nature of your mids without completely removing them. This opens the doors to many new tone sculpting possibilities. On the Carvin Audio BX1600, the contour knob allows gradual scooping of the mids to tame the clutter in the midrange. When set to the leftmost position, the mids are unchanged. Turn the knob to the right and you will incrementally scoop your mids out at about the 250Hz range- this is the range where a lot of the body and low midrange heft of your bass sound is. Too much sound in this range can be detrimental and really muddy up a mix, but the contour knob really lets you find the sweet spot. At full clockwise the midrange content at 300Hz is reduced by 9dB.

If you’re a fan of the scooped mids sound, it can be very useful to find equipment that lets you implement it into your sound gradually via a knob rather than all at once (some amps have a simple on/off switch for a mid scoop function). Don’t be afraid to experiment with the contour control next time you’re playing with the band- it’s another important and often overlooked tool to help bassists in finding the right tone.


  • Posted On October 22, 2016 by Kevin Cress

    I LOVE CARVIN!! I have 5 Carvin power amps and a BX1600 bass amp and a Carvin mic. I have a friend that has bass cabinets and another that has speakers and everything sounds great. I like that it is American made. The techs are helpful and friendly. The articles on how to improve your sound and use the different features on the equipment are very useful and I look forward to each one. Hoping to build my perfect Cavin Vanquish Bass one day with their custom shop. Carvin knows how to do it right! – Kevin Cress

  • Posted On October 18, 2016 by Mario Sangermano

    I have the MB15 micro bass amp and all I can say Is I love It. It’s a very loud amp for its size. I love the fact that it has very very minimal colorization . I usually keep my contour at around 10 o clock.
    I also have the BX 1600 amp and BRX 4/10 cabinet. Just great stuff from you guys. Keep up the great work.

  • Posted On October 18, 2016 by Woody

    Excellent explanation. I love a good bass mid cut to get rid of those annoying nasal tones. Guitar should have mid boosts. Bass should have mid cut. Thanks for the clear explanation on how to use the contour control.

  • Posted On October 18, 2016 by monty

    good call.. I just realized this is true… many basses are to trebly .. they may sound good alone but in a band they don’t work so well…

  • Posted On October 18, 2016 by Uncle Ralph

    You said it: Clutter in the midrange. People get really tired of listening to cluttered midrange even if they don’t know what to call it and aren’t really even sure what they are tired of. This is the appeal of the famous Gibson Varitone control used on the ES-345 and ES-355 guitars. All it does is scoop the midrange at various frequencies and makes a noise that is clearer, better defined and more interesting than the ubiquitous Ever Honk emitted by the inescapable humbucking pickup.

    In the world of electric bass, that crap in the 250-300Hz band is what makes bass sound woofy and muddled. Many, many bass players just let it be loud and muddy. In fact, that’s what way too many people think a bass is supposed to sound like. Taking some of that muffled growl out makes the bass a lot clearer and far more listenable.

Leave a comment

All blog comments are checked prior to publishing