The audiophile hobby is guilty of a lot of things, perhaps the most painful of which is our overreliance on often-confusing terminology. This is the case for nearly every category of the hobby. On the pages of FutureAudiophile.com, we try not to assume that everyone understands every topic and term, so we often link to other internal articles as well many a Wikipedia page here and there. But maybe you don’t want to follow those links. Maybe you want one article that explains what you need to know. That’s the goal here, starting with audiophile loudspeakers, since we review a number of those and they one of the most important parts of your sound system. Here are some key terms and deeper explanations of them.
What is Soundstage and/or Imaging?
These terms may seem interchangeable, but while somewhat related, they’re actually quite different phenomena. Soundstage is a recreation of a place or venue where a musical presentation is given, or a believable illusion thereof. For these examples I am using live music examples, but by all means soundstage and imaging are relevant in studio recordings too. Imagine a heavy metal concert performed in an open-air football stadium. That would sound very expansive, right? Think next about an orchestra on a stage in a performing arts center. Still a mostly expansive presentation, but not like a football stadium. Lastly, imagine a three-person acoustic jazz combo in a small nightclub with low ceilings. Such a venue would sound much more intimate in terms of the soundstage.
Our goal is to enable the recording and the system to give us the feeling we are at the specific venue when the music was performed live. We want to audibly tell the difference in how the music feels when comparing a football stadium and a confined jazz club.
Imaging is a subset of soundstage. Specifically, imaging is where on the soundstage the various musicians are placed. Imagine attending a concert of a symphony orchestra. You are sitting in the center of the stage about four or five rows back. You can easily see where the performers are positioned. For simplicity’s sake (most orchestras are not arranged this way), suppose the string section is stage right. Woodwinds are stage left. Percussion, or the kettle drums and cymbals are in the middle but in way the back. And right up front, right in the middle of the stage is a piano. You can easily see where the musicians are located.
Because our human hearing allows us to discern directionality, we also can close our eyes and reasonably tell where the musicians are located. If a flautist standing to the far left of the stage performs a solo, and essentially regardless of where you are seated, you will pretty much know where the performer is located – even if your eyes are closed.
In an audio system, one of the main goals is to achieve an image presentation in the room where the stereo system is located. Imaging for an audio system is based on three primary factors: the recording, the system (electronics, speakers, and so on), and the room itself. We plan to have an article on room acoustics in the future. But for now, what audiophiles are seeking in regard to imaging is to be able to readily tell where specific instruments are located when sitting in a listening chair. Why? Simple. It makes the listening process much more enjoyable because it gives the feeling of attending a live show. You can follow the position of the instruments in the audio room with your eyes. Imaging is also one of the more difficult aspects of setting up an audio system.
What is Sonic Clarity?
Distortion is the enemy of any audiophile system. We want a musical presentation to be as free from distortion as possible. We want a clean, clear, unimpeded sound of the music we enjoy. We don’t want instruments to sound fuzzy unless they’re supposed to sound fuzzy. We want a very clear sonic presentation. That’s what we would call clarity.
What is Accuracy When It Comes to Audiophile Sound or Speakers?
In order for a song to sound believable, it must have accuracy. Sure, that makes perfect sense and is almost a tautology. Think about a piano for a minute. When playing the single Middle C key, a specific frequency is emitted into the room. Striking the key very forcefully or softly doesn’t matter – the same frequency is produced. And for the record, the frequency of Middle C is 256 Hz.
Add in one of the black keys or maybe you add in a second white key and now you have created a chord. A piano is one of the more difficult instruments for an audio system to accurately and perceptibly reproduce due to infinite chord variations. Above all else, we want our system to portray a piano, and all instruments, with high precision. We want to easily be able to tell the difference between a violin and a viola – and between a bass and a cello.
What is a Decibel?
This is a unit of measure indicating how loud a sound is. It is abbreviated as dB. For instance, normal conversation is about 50 dB while a rock concert may measure at roughly 100 dB to 110 dB. A jet engine measures at around 140 dB. Too high of a decibel level cause hearing loss and, depending on the levels, that can happen very quickly. It is therefore important to listen responsibly when rocking your audiophile system, and most notably with your headphones or earbuds.
What Is Sensitivity with Regard to Speakers?
This is an electrical term whose definition is the Sound Pressure Level (SPL) produced by a speaker when fed a given amount of power, measured from a certain distance away. If a loudspeaker’s sensitivity is listed as 80 dB, what that actually means is with one watt of amplifier power measured at a distance of one meter, 80 dB of sound will be produced. This is commonly written as 80dB/1W/1M. More often, when reading a speaker’s technical specifications, sensitivity will be listed as a single number, say 80 dB. The rest of the spec is implied. Higher sensitivity means the speaker will more easily fill the room with volumes sound. Higher sensitivity also means a higher room SPL with less amplifier power because of greater efficiency. Electrostatic speakers tend to be stereotypically low sensitivity with horn-style speakers being much higher.
What Do We Mean by Dynamics?
This term actually has several meanings, but in this context, dynamics gives music body and weight. It creates musical power, if you will. When a piece of music has significant dynamics, the presentation will feel powerful and will give the listener an almost visceral feeling of intensity. For many audiophiles, dynamics and the weight and power produced are what makes the audiophile hobby more interesting. Dynamics and dynamic range (listed below) are closely tied together.
How Do We Define Detail?
When we hear music on a low-resolution source component, we often miss out on the very intricate cues contained in all music. These cues are sometimes called transient detail – or music that comes and goes rather quickly. On a top-level audiophile system, being able to hear the fine details is important because it helps establish a greater level of believability in the musical reproduction. When we can hear a singer take a breath or his or her fingers making sounds when moving up and down a fret board on a guitar, it makes the listener somewhat feel they are hearing the music performed right in front of them.
What About Impedance?
Impedance is a measure of resistance in an electrical circuit. As it relates to a loudspeaker, it is a measure of the opposition to the flow of current in an electrical circuit. Why is this important to a loudspeaker system? Understand first that a speaker and amplifier work very closely together. A speaker’s overall performance is directly tied to the amplifier. So having compatibility between these two components is a very good idea.
Speaker impedance is measured in Ohms. Many small stand-mount speakers have a rated impedance of 8 Ohms. It is not uncommon for large floorstanding speakers with bass, midrange, and treble drivers to be rated at 4 Ohms. Generally speaking, an 8 Ohm load is significantly easier to drive than a 4 Ohm load. While found more often in speaker designs of the past, a 2 Ohm load is not only pretty hard for an amp to drive but it is rare to see these days.
In an audio system, turning up the volume and how loud the system sounds is not a one-to-one ratio. In fact, it is far from it. In order to increase the SPL by just 3dB, the power output of the amplifier must be doubled. To go, therefore, from a SPL of 80dB to 83dB, the amp must double in wattage. To go from 83dB to 86dB it must double again. And so on…
What this means is when choosing a 4 Ohm speaker system, it is important to be sure the amplifier will double (or close to it) in wattage output when the impedance is halved. If, for instance, an amplifier is rated at 200 Watts Per Channel at 8 Ohms it should be also be rated at (or nearly) 400 Watts at 4 Ohms. This is important because it is always better to have an abundant amount of power as opposed to not enough. So when provisioning your audiophile system while on your journey in this hobby, be sure that the amp that you choose is rated accordingly before settling in on a new amp and speaker system.
What Does Dynamic Range Mean?
Closely related to Dynamics (listed above), this is the difference in SPL of the softest sound in a recording as compared to the loudest. Think about how a very soft flute solo sounds. It may be barely audible from the cheap seats. And when the full power and force of that massive 50-piece orchestra comes rolling in, the decibel output goes up sharply. The audible difference in decibels between the flute solo and the full orchestra is Dynamic Range. Rap, country, heavy metal, and rock have little Dynamic Range. Classical music has quite a bit. Jazz would be somewhere in the middle. Here is an example from an audiophile classic “Bring the Boys Back Home” from The Wall via YouTube.com. Note how the song starts with a marching drum and explodes into a huge choral and orchestral section then settles back to more subtle musical details.
Dynamic range also ties back into impedance and sensitivity ratings. A recording with wide dynamic range should deliver a significant punch and feeling of power at a loud listening levels. A speaker/amp combo that is mismatched or underpowered may present the drums or any low frequency with very little impact. Treble sounds, like a cymbal crash, may be almost inaudible. Any of these conditions are the result of a mismatched amp to the speaker or an amplifier with far too little power. This is why a $399 all-in-one stereo from the drug store store sounds increasingly lousy as the volume is increased. This system simply lacks the power to adequately drive the speakers. Compare that to a slightly higher-end system driven by a power amplifier with output wattage to spare and a properly matched speaker system and prepare to be impressed. That combination will have little problem energizing the room and filling it with sound played back at almost any decibel level the listener may desire.
What Does Frequency Range Mean?
Frequency range defines the lowest and highest frequencies a speaker system will recreate. If the specs list the range as 30 Hz to 20 kHz (or 20,000 Hz), any sounds below or above those ratings will not be heard. If your favorite music has a passage with a massive pipe organ, if you want to hear it as it was recorded, a speaker system with low bottom-end frequency capability will be necessary. Many speaker systems simply cannot produce frequencies low enough for a pipe organ or similar instrument. To do so may require the use of a subwoofer. It is recommended to choose a speaker system with the capability to reproduce a wide range of frequencies so the musical presentation will be natural sounding. Generally speaking, small bookshelf speakers have less frequency range than large floorstandingversions.
What is a Loudspeaker Crossover?
Music has three principal frequency ranges: bass, midrange and treble. Generally speaking, bass sounds are typically between 20 Hz to 300 Hz or so. Midrange is 300, maybe 400 Hz to about 4 kHz (4,000 Hz) and treble is anything above that. These ranges are in no way absolute levels. What does matter is that a single driver cannot accurately process all three ranges of sounds, so most speakers are designed to have one driver (or more) dedicated to delivering the bass, one or two to the midrange, and one or several to specializing in high frequencies.
A crossover network separates the frequency ranges in the electrical signal and sends them to the appropriate driver, be it a woofer, mid-woofer, or tweeter. In a three-way speaker system, the crossover will divide the signal into three parts, and in a two-way system, it will divide it into basically bass/midrange and treble. The actual frequency where the crossover divides the frequencies is strictly up to the speaker manufacturer based on their own design.
What Are the Different Types of Common Audiophile Speaker Designs?
There are all sorts of loudspeaker designs developed over the years. Some highly respected audiophile speaker gurus suggest that there hasn’t been a truly new speaker technology in more than 75 years, but with that said there are plenty of speaker designs and unique permutations. The most traditional speaker is a dynamic speaker, which typically has a least a tweeter, a midrange, and possibly a bass driver. The examples of this are endless, from a Bose to a Wilson Audio product. Planar speakers are a bi-polar (meaning firing both ways) that look like tall, thin towers. Magenpans are a good example of a planar speaker. A dynamic speaker that is bi-polar, though, would be say one from Definitive Technology. There are all sorts of electrostatic speakers on the market including ones from Sound Lab from Utah, Quad from England, or even hybrid electrostatic speakers from MartinLogan ESL. An example of that is their ESL speaker. It has a traditional woofer on the bottom and then a curved, powered electrostatic panel above. There are in-wall speakers as well as invisible speakers, which are sonic transducers that you can cover with fabric, wallpaper, wood, or even drywall and they disappear. Obviously, there are subwoofers, which are a great way to get the deepest of frequencies into your audiophile system. I am glossing over all sorts of other varieties and configurations of speakers but this gives you a good overview of the commonly found designs and some of their parts. Perhaps we will expand on this topic and get into more esoterica such as folded motion tweeters or D’appolito Arrays and more. Stay tuned.
Summary of Audiophile Speaker Terminology…
Most audiophiles listen to music in two principal modes: for the simple enjoyment of hearing a favorite song or listening in a critical and evaluation-oriented mode. We want to both enjoy a song and also need to be sure the sonics produced are the best we can manage to create. Speakers are unique in an audio system because they are the one part of an audio system actually converting an electrical signal to sound. Don’t discount the close relationship of an amplifier to a speaker system. Understanding the terms used in audio publications will help the reader better understand the meaning of what was written. And if better understanding helps create a better listening experience, that audiophile has a reason to smile. There can certainly be nothing wrong with listening to music with a smile on your face. Out hobby is intended to be fun. That’s what really matters.
Good article for those who are new to the hobby or simply haven’t given these topics much thought to pin down their exact meanings. Don’t want to confuse people, but I do want to mention that decibels are a logarithmic measurement. Don’t worry, this isn’t a math class. The main thing to know is that every 3dB is a doubling of power, so there is a huge difference in the sound energy from a conversation at 50dB to a jet engine or a Ted Nugent concert at 140dB.
Yeah, I was trying to keep it simple.
You have provided an important service to mankind. Thank you.
I would have loved a brief discussion on a speaker design concept that is too often overlooked — it is the answer to a lot of ears that are sensitive to timing and time alignment errors inherent in 3-way tower speakers. I’m talking about Dual Concentric. A design that eliminates that ‘disjointed’ sound from most 3-way towers speakers. It is used by KEF, Tannoy, Zu, Fern & Roby, and I’m sure other speaker manufacturers. It usually consists of a tweeter sitting inside a woofer — for a two-way design. I spent a fortune chasing good sound on 3-way tower speakers (and amps to “match” them) before someone suggested Dual Concentric. Check it out.
Thank you for your kind words.
More on this front is coming soon. Stay tuned.
We can’t assume a whole new generation of readers understand fully all of these terms thus the guide to how to understand them! 🙂
Thanks Hoyt!!
Much Appreciated!
It would be fair to give credit where credit is due.
And when it comes to the audiophile lexicon, it would be Harry Pearson who would be due that credit. While Harry and J. Gordon Holt took a similar, subjective approach when reviewing audio products, Harry applied his skill as a wordsmith to describe his listening experience, what he heard from different products and combinations of products.
Harry’s subjective approach did not rely on specifications, albeit important ones, like speaker impedance and sensitivity–duly noted in the article–remained important for proper system matching.
As for the middle C frequency of 256 Hz (actually 256.87 Hz), it might be worth noting 256 Hz would be the case when middle A is 432 Hz.
With more orchestras tuning at 440 Hz (some as high as 442) middle C moves to 261.63 Hz.