Terms Used To Describe How A Loudspeaker Sounds

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Describing Loudspeaker Sound

In the course of my work for Axiom, I answer lots of email technical questions on the "sound" of Axiom speakers (as well as that of our competitors' products). One recent email questioner said that he wanted a loudspeaker that embodied the "rich" sound he heard from a live orchestra in a concert hall.

But what did he mean by the adjective "rich"? Did my understanding of "rich" parallel his? Did he mean "rich" as a compliment? (Amongst us picky reviewers, "rich" can sometimes be used as negative quality of a speaker.) What if each of us took away entirely different meanings of the same word? Endless confusion and misunderstanding might ensue. So you see the need for a standardized vocabulary used to describe particular qualities of sound from a loudspeaker, both good and bad.

This isn't a new problem, of course, so I tried to determine exactly what he meant by "rich". Turns out that he meant a full, rounded sound with lots of deep, sonorous bass (more adjectives!). I pointed out that while a fine concert hall and a good recording should preserve and even enhance those qualities, a "neutral" and "linear" speaker will also reproduce them (given that the speaker has smooth, extended bass response) but that the speaker shouldn’t by itself confer a "rich" sound on all music played through it. If it did, that "richness" could become a tiresome bass "coloration": it might sound great on some music but not so good on other types. In fact, among reviewers, "rich," "ripe" or "chesty" is often used as a criticism for loudspeakers that have too much upper bass emphasis, which give male voices a "fat" unnatural coloration.

What follows is a list of standard terms that have evolved from years of loudspeaker listening tests in which I participated, conducted at Canada's National Research Council (NRC) acoustics lab. I've taken the list from forms originally compiled by Dr. Floyd Toole during his long tenure at the NRC Acoustics Division for use in subjective double-blind listening tests, as well as additions from my own notes during those tests and those of other long-time reviewers, including Ian G. Masters. The forms and adjectives we used were to solve this very problem, because sometimes reviewers can become almost poetic in their descriptions of loudspeaker sound, as if the speaker were a musical instrument in and of itself! For instance, does a term like "chocolaty midrange" have meaning for anyone other than the writer who used it? Does it mean that the sound is smooth, thick, or dark? And is it a criticism or a compliment? Who knows?

Here are some common terms to describe loudspeaker sound. "Forward" indicates that vocals, male and female, tend to be very present, almost as if the singer were standing in front of the plain of the speakers. It can be a negative term, too--if singers sound too close up it may mean the midrange is boosted or exaggerated. The opposite is "recessed," which means that midrange sounds like singers and choruses seem to be farther back, a bit distant-sounding and well behind the plain of the speakers.

"Spacious" and "open" and "airy," all positive traits, describe the sense of space present around the instruments and singers; it relates to the speaker's presentation of the stereo "soundstage" (the three-dimensional positioning of the instruments across an imaginary stage) in addition to how well it reproduces the ambient sounds present in the original recording. The opposite is "closed," "muted" or "dry," which indicate the midrange and treble are rolled off or depressed and dull.

Words like "sibilant" mean the speaker has a midrange/treble peak that emphasizes the "sss" and "ttt" sounds of singers’ vocals. The same speaker might also be a bit "bright" (a little treble emphasis) or quite "strident" (way too much treble output, making brass and string sound shrill or harsh).

"Thin" means the speaker has little or no bass output, while "boomy" means it has too much bass that dominates its sound. "Punchy" can be quite pleasing and powerful upper bass, like a disco, but no really deep bass. "Muddy" or "muddled" means the midrange isn't clear; that it's hard to separate the distinct contributions of male and female singers in a chorus.

If a speaker has real problems in the midrange, either a big "suck-out" or valley or other uneven response, terms like "boxy" (vocals sound as if the singer were inside a box) or "honky" are useful. Another common coloration is "nasal," which describes what a midrange peak does to vocals, like what happens to your voice when you cup your hands around your mouth while you're speaking.

Now that you are armed with the right descriptors, you can analyze the sound you hear from speakers in a store demo, at a friend's house (be careful with words like "honky" or "boxy" around friends!) or from your own loudspeakers. Go ahead, try these terms out on our message boards!

by Alan Lofft (bio), Axiom Audio (reprinted with permission)

Author	Comments
Anonymous	Posted on Thursday, December 30, 2004 - 06:37 pm:    Some more terms from the Audio FAQ Airy: Spacious. Open. Instruments sound like they are surrounded by a large reflective space full of air. Good reproduction of high-frequency reflections. High-frequency response extends to 15 or 20 kHz. Bassy: Emphasized low frequencies below about 200 Hz. Blanketed: Weak highs, as if a blanket were put over the speakers. Bloated: Excessive mid-bass around 250 Hz. Poorly damped low frequencies, low-frequency resonances. See tubby. Blurred: Poor transient response. Vague stereo imaging, not focused. Boomy: Excessive bass around 125 Hz. Poorly damped low frequencies or low-frequency resonances. Boxy: Having resonances as if the music were enclosed in a box. Sometimes an emphasis around 250 to 500 Hz. Breathy: Audible breath sounds in woodwinds and reeds such as flute or sax. Good response in the upper-mids or highs. Bright: High-frequency emphasis. Harmonics are strong relative to fundamentals. Chesty: The vocalist sounds like their chest is too big. A bump in the low-frequency response around 125 to 250 Hz. Clear: See Transparent. Colored: Having timbres that are not true to life. Non-flat response, peaks or dips. Crisp: Extended high-frequency response, especially with cymbals. Dark: Opposite of bright. Weak high frequencies. Delicate: High frequencies extending to 15 or 20 kHz without peaks. Depth: A sense of distance (near to far) of different instruments. Detailed: Easy to hear tiny details in the music; articulate. Adequate high-frequency response, sharp transient response. Dull: See dark. Edgy: Too much high frequencies. Trebly. Harmonics are too strong relative to the fundamentals. Distorted, having unwanted harmonics that add an edge or raspiness. Fat: See Full and Warm. Or, spatially diffuse - a sound is panned to one channel, delayed, and then the delayed sound is panned to the other channel. Or, slightly distorted with analog tape distortion or tube distortion. Full: Strong fundamentals relative to harmonics. Good low-frequency response, not necessarily extended, but with adequate level around 100 to 300 Hz. Male voices are full around 125 Hz; female voices and violins are full around 250 Hz; sax is full around 250 to 400 Hz. Opposite of thin. Gentle: Opposite of edgy. The harmonics - highs and upper mids - are not exaggerated, or may even be weak. Grainy: The music sounds like it is segmented into little grains, rather than flowing in one continuous piece. Not liquid or fluid. Suffering from harmonic or I.M. distortion. Some early A/D converters sounded grainy, as do current ones of inferior design. Powdery is finer than grainy. Grungy: Lots of harmonic or I.M. distortion. Hard: Too much upper midrange, usually around 3 kHz. Or, good transient response, as if the sound is hitting you hard. Harsh: Too much upper midrange. Peaks in the frequency response between 2 and 6 kHz. Or, excessive phase shift in a digital recorder's lowpass filter. Honky: Like cupping your hands around your mouth. A bump in the response around 500 to 700 Hz. Mellow: Reduced high frequencies, not edgy. Muddy: Not clear. Weak harmonics, smeared time response, I.M. distortion. Muffled: Sounds like it is covered with a blanket. Weak highs or weak upper mids. Nasal: Honky, a bump in the response around 600 Hz. Piercing: Strident, hard on the ears, screechy. Having sharp, narrow peaks in the response around 3 to 10 kHz. Presence: A sense that the instrument in present in the listening room. Synonyms are edge, punch, detail, closeness and clarity. Adequate or emphasized response around 5 kHz for most instruments, or around 2 to 5 kHz for kick drum and bass. Puffy: A bump in the response around 500 Hz. Punchy: Good reproduction of dynamics. Good transient response, with strong impact. Sometimes a bump around 5 kHz or 200 Hz. Rich: See Full. Also, having euphonic distortion made of even-order harmonics. Round: High-frequency rolloff or dip. Not edgy. Sibilant: "Essy" Exaggerated "s" and "sh" sounds in singing, caused by a rise in the response around 6 to 10 kHz. Sizzly: See Sibilant. Also, too much highs on cymbals. Smeared: Lacking detail. Poor transient response, too much leakage between microphones. Poorly focused images. Smooth: Easy on the ears, not harsh. Flat frequency response, especially in the midrange. Lack of peaks and dips in the response. Spacious: Conveying a sense of space, ambiance, or room around the instruments. Stereo reverb. Early reflections. Steely: Emphasized upper mids around 3 to 6 kHz. Peaky, nonflat high-frequency response. See Harsh, Edgy. Strident: See Harsh, Edgy. Sweet: Not strident or piercing. Delicate. Flat high-frequency response, low distortion. Lack of peaks in the response. Highs are extended to 15 or 20 kHz, but they are not bumped up. Often used when referring to cymbals, percussion, strings, and sibilant sounds. Telephone-like: See Tinny. Thin: Fundamentals are weak relative to harmonics. Tight: Good low-frequency transient response and detail. Tinny: Narrowband, weak lows, peaky mids. The music sounds like it is coming through a telephone or tin can. Transparent: Easy to hear into the music, detailed, clear, not muddy. Wide flat frequency response, sharp time response, very low distortion and noise. Tubby: Having low-frequency resonances as if you're singing in a bathtub. See bloated. Veiled: Like a silk veil is over the speakers. Slight noise or distortion or slightly weak high frequencies. Not transparent. Warm: Good bass, adequate low frequencies, adequate fundamentals relative to harmonics. Not thin. Also excessive bass or midbass. Also, pleasantly spacious, with adequate reverberation at low frequencies. Also see Rich, Round. Warm highs means sweet highs. Weighty: Good low-frequency response below about 50 Hz. Suggesting an object of great weight or power, like a diesel locomotive.
James Hutchinson New member Username: Jimboh2k Post Number: 2 Registered: Jul-05	Posted on Monday, July 25, 2005 - 11:00 pm:    Wow, so many words. I was wondering what people meant by muddy bass. Thanks
Gavin R. Cumm Gold Member Username: Gavincumm New York USA Post Number: 1147 Registered: Feb-05	Posted on Wednesday, May 17, 2006 - 02:43 pm:    lol...I have ALWAYS thought the bose AM series to sound tinny. Even when I was 14 hearing one for the first time, that was my impression.