A Guide To Better Bass (TAS 197)

Accurately reproducing music’s low frequencies is the single biggest challenge facing the audiophile. The laws of physics make it difficult to achieve a smooth, extended, and articulate bottom end in our listening rooms. Consequently, many of us live with less than great bass performance.

 But wonderful-sounding bass is immensely rewarding musically. The bottom end forms the tonal foundation of some types of music, and in others bass is the source of music’s rhythmic drive, propulsion, and energy. The visceral, whole-body experience of a great drummer and bass guitarist locking into a groove—the kick drum’s transient and the attack of the bass guitar strings combining synergistically—is one of music’s supreme pleasures (at least for me).

In this “Guide to Better Bass,” we’ll look at how you can improve the bottom end of your existing audio system, explore different options if you’re just starting out or upgrading, and consider some general principles for getting great bass.

Let’s start with some fundamentals about bass reproduction. Despite what I just wrote about the importance of bass, it’s possible to put together an extremely involving music system based on smaller speakers that don’t reproduce bass below about 50Hz. This is particularly true for listeners whose tastes lean toward chamber and smaller-scale works in classical music, singer/songwriters in pop, and acoustic jazz. Listeners with those musical inclinations are better off with smaller speakers with limited bass response than with full-range speakers of a similar price that may be compromised throughout the entire sonic spectrum.

Second, bass quality is vastly more important than bass quantity. A leaner presentation without much extension is preferable to lots of bass if that bass is thick, colored, and sluggish. If the bass isn’t well reproduced, we’d rather not hear it at all. The poor bass performance becomes a constant annoyance and a reminder that we’re listening to a reproduction. This is why a superbly engineered mini-monitor can be more musically involving than a large floorstanding speaker.

Third, accurate bass reproduction is expensive. The lower the frequency accurately reproduced, the more expensive bass becomes. Note the word “accurate” in both sentences; you can buy a $500 loudspeaker that has output below 40Hz, but it’s unlikely that the bass it produces will be accurate. Realistic reproduction of the bottom octave (16Hz–32Hz) requires large woofers, which in turn requires a large cabinet. The larger the cabinet the more prone it is to vibration that will color the sound. Enclosure vibration colors the music tonally and destroys music’s dynamic structure. The solution is to build heroic enclosures that don’t vibrate, but such enclosures are extremely dense, heavy, and expensive.

Fourth, a system’s bass presentation affects such seemingly unrelated aspects of the sound as midrange clarity and soundstaging. Thickness in the midbass reduces the midrange’s transparency. A cleaner midbass not only makes the midrange sound more open, it also lets you hear more clearly into the extremely low frequencies. Moreover, extending a system’s bottom end has the odd effect of increasing soundstage depth and our overall sense of the recorded acoustic, even on music with no low-frequency energy. I’ve heard an unaccompanied voice in a large hall reproduced by a pair of mini-monitors with and without a subwoofer. Adding the subwoofer revealed the full extent of the hall’s size, as well as presented the vocalist as a more tangible image within the acoustic.

With those concepts in mind, let’s see how we improve a system’s bass performance.

Match the Speaker to the Room

The deeper the loudspeaker’s bass extension and the more bass output it produces, the larger the room needed to realize great bass performance. Lots of very low bass will overload a small room, making it almost impossible to get smooth response. This fundamental fact is played out countless times at hi-fi shows as exhibitors fight to get a large full-range loudspeaker to work in a hotel room. If you choose too much speaker for your room, you’ll wage an uphill battle in getting good-sounding bass.

Loudspeaker Placement

Correctly positioning your loudspeakers is the single most important thing you can do to achieve better bass. The topic is beyond the scope of this article, but you can get an idea of its importance from the accompanying sidebar “The Physics of Bass.” For specific loudspeaker-placement techniques, download the free booklet “Robert Harley’s System Set-Up Secrets” at avguide.com/hifibooks. The booklet is an excerpt from The Complete Guide to High-End Audio (Third Edition).