Speakers Product Guide
Whenever you listen to music from a radio, stereo system, television, and almost any electronic device, the sound is coming from a speaker. Even those headphones that you use with personal stereos have little speakers (called drivers) inside them. This section discusses the terminology that will help you purchase a set of speakers for an audio component system.
There are basically two types of sound that a component system may deliver:
- Stereo - 2 Channels, requires 2 speakers. One speaker for the left channel and one for the right channel.
- Home-Theater Surround - Usually 5 Channels, requires 5 speakers. Like stereo, 2 of the front channels cover the left and right speakers. There is also 1 front center speaker. In addition, there are 2 rear channels (left and right). Dolby Pro-Logic, Dolby Digital, DTS and THX are the popular home-theater surround formats currently available.
When we discuss speakers, those designed for use with component systems really should be referred to as speaker systems because a speaker is likely to have two or more speakers in a cabinet. Each of those speakers may be linked to a little electronic device called a Crossover. This is why they're called speaker systems. What appears as a speaker cabinet may actually contain a series of speakers and electronic devices, working together to deliver fine sounds.
Speaker systems come in a wide-range of styles and sizes. There are speakers designed to be placed on bookshelves or placed on the floor. There are speaker systems that are made to be placed inside a wall. There are wireless speakers and weather-resistant, outdoor speakers.
Speakers must always be connected to a component system. With the exception of wireless speakers, virtually all speakers must be connected to an amplifier or receiver with speaker wires, which carry electronic signals to the speaker. Using thicker wires made with high-quality (high conductivity) wire, allows those signals to be transferred with greater accuracy and integrity.
The concept behind a speaker system is to deliver an accurate reproduction of the original sounds that were recorded on a CD, DVD, Vinyl Record, Tape or live radio broadcast. The ideal speaker system should be neutral, adding no tones of its own to the original recording. Not all speakers can attain this ideal and you can find yourself spending thousands of dollars trying to buy a speaker system that is neutral. Most of the speakers that we sell are practically neutral - they may have certain properties that lend themselves to particular types of music - but can equally be reasonably faithful to all types of music.
Tweeters and Woofers
A component system reads the sounds recorded on a disc or tape (or broadcast over radio waves) and converts them into electronic signals. These signals consist of layers of frequencies from very low to very high. The range of frequencies that a speaker can deliver is known as the frequency response. Frequencies are measured in cycles or vibrations per second - Hertz (Hz). Human hearing, under optimal conditions, is 20Hz to 20,000Hz. Most speaker systems follow close to that range.
Speakers deliver sound by taking the electronic signals coming from an amplifier or receiver and converting them into vibrations. The speaker interprets the frequencies of the music as vibrations. Lower frequencies (20Hz to 200Hz) are slower vibrations that move larger volumes of air - deep bass, rich, full, penetrating sounds. This type of speaker delivers large sounds and, coincidentally, is large (usually over 5 inches diameter). It's called a Woofer. Imagine the bark of a large dog - deep and loud.
Higher frequencies move less air per cycle but, because they're faster, produce higher sounds - reminiscent of violins and flutes. A speaker that produces these sounds would tend to be smaller (usually about 1 inch diameter) and because it's really effective at producing high, birdlike sounds, it's called a Tweeter.
There are frequencies that also fall in between that are neither deep nor high. Vocals (singers) tend to cover this range. Because it covers the range under the tweeter and above the woofer, it's called the Mid-Range.
The Woofer, Tweeter and Mid-Range are types of speakers. In recent years, to avoid confusing them with speaker systems, they are called Drivers. Each type can drive a particular range of frequencies.
Woofer sizes may typically range from 5-inches to about 15 inches diameter. Most tend to be 8 inches, 10 inches and 12 inches. Tweeters may range in size from as large as 2 inches to as small as a ½ inch. Most are around 1 inch. Mid-Range drivers may be anywhere from 3 inches to about 5 inches in diameter.
So signals are fed into your speaker system from your component system. Let's say each speaker system (channel) has two drivers, a tweeter and a woofer. How can you distinguish which frequencies might go to each driver? That's the job of the crossover.
The crossover is an electronic device that would direct signals below 2000Hz to the woofer and over 2000Hz to the tweeter. Different speaker systems may have different parameters (frequency points) that crossovers administer. This can sometimes determine how neutral a speaker is. Some speakers may lean toward deep frequencies, others to mid-range and others to highs.
The number of drivers in a speaker system helps determine the paths or ways the sound is delivered. Two drivers in a cabinet (with one crossover) is a 2-Way speaker system. Three drivers in a cabinet (with 2 crossovers) would be referred as a 3-Way speaker system.
Speaker Loudness or Sensitivity
Speaker Systems may have a power rating. This means that an amplifier or receiver must have a certain quantity of watts to properly operate that speaker. Many speaker systems can handle 10 to 100 watts per channel.
A speaker may also have an SPL (Sound Pressure Level) rating which means how loud will a speaker be when given a minimum power input of 1 watt. This is measure in decibels (dB = a standardized rating for loudness). Most speakers might have an SPL ranging from 80dB to slightly over 100dB. The higher quantity of dB means the louder sound (volume) that the speaker can deliver from the same amplifier power.
Impedance or Ohms
There's a rating called Ohms and it relates to the resistance (impedance) of signal flow from your amp/receiver to your speaker system. Most amps and receivers are rated at 8 Ohms, although more models are being released with a 4-Ohm to 8-Ohm range. Speaker Systems can be nominally rated at 8 Ohms, for example. The impedance factor has nothing to do with sound quality but has something to do with the work that the speaker and receiver must do together to deliver sound. A receiver rated at 8-Ohms and a speaker rated at 8-Ohms (essentially a match) is the best association. If you use speakers with an Ohm rating lower than your amplifier is rated for, it is possible that your amplifier may overheat which may result in damage to the amplifier or to the speakers.
Types of Speakers
These speakers are used for left and right channel reproduction. They're called Shelf speakers because they are relatively compact sized and can fit on most bookshelves. Because they have smaller cabinet sizes, the drivers may be smaller. Shelf speakers can deliver excellent music reproduction. Because of their smaller size, however, their output in the lower frequency ranges (bass) will not equal an equivalent larger (Floor-Standing) speaker.
Shelf speakers may be ideal for delivering stereo sound in small rooms. They are also very popular as Rear speakers in a home-theater component system.
Because Floor (or Floor-Standing) speakers are much taller and bigger, there's very little compromise with the size of drivers. They can deliver exceptional sound to large rooms and may deliver the widest dynamic frequency response range.
Floor-standing speakers are used as the front left and right speakers of high-quality home-theater or stereo systems.
In a home-theater surround sound system, the Center-Channel reproduces the sounds you might hear directly behind the screen in a movie theater. Much of that is associated with dialog and effects. These speakers tend to lean toward mid-range and bass frequencies for best representation of those sounds. Since the Center Channel handles the majority of the dialog in movies, it is important not to skimp on the quality of this speaker when you budget for a Home-Theater component system.
Another space-saving solution to home speakers is units that are mounted inside walls. These speakers are relatively small and usually come in pairs. They can be mounted basically anywhere, in walls or ceilings. You should try to check if your wall or ceiling has enough clearance to accept the installation of the speaker that you may want to buy.
Outdoor speakers are specifically designed for playing background music at parties or conferences that take place outside. Most models are designed to resist a wide-range of weather conditions including moisture and snow. A few models are wireless and receive signals from your component system using an FM wireless transmitter.
Wireless speakers get rid of wiring tangles quick enough. They work using radio frequencies to bring decent sounding audio. Most wireless sets come in pairs of two speakers.
This is a special class of speaker that has grown in popularity over recent years. It is designed to deliver extremely low frequencies, below those that most woofers can reach. That's why it's called a Subwoofer. They are especially popular when used with home-theater surround sound systems because they can help deliver that Big-Theater sound.
Many current stereo and home-theater receivers (especially those that have Dolby Digital Surround Sound) now have a port for connecting a subwoofer. Since it takes a great deal of power to reach those exceptionally low frequencies, virtually all subwoofers have built-in amplifiers.
Subwoofers deliver the deep bass for all the channels in a home-theater set-up. Only one subwoofer is required per component system.
All speakers (except Wireless models) require Speaker Wire for connection to audio receivers and amplifiers.
Because this wire is responsible for efficiently carrying the electrical signals from the receiver to the speaker, it's important that the wires be good conductors. Thicker wires (usually about 14 gauge) and copper or gold-based wiring offer the best signal transfer.
Wire connects to amplifiers and receivers using U-Ring adapters, Angle-pins or Banana Plugs (depending on the speaker or receiver connectivity ports). These are known as Terminators because they connect to the ends of the wire. In many cases, these terminators are gold-plated to assure optimal signal transfer.
When seeking excellent connective wires, we recommend using Monster Cable brand wires. Speaker wire is sold in rolls (without terminator plugs), or in pairs or kits (with terminator plugs already attached). Please check our hook-up diagrams for help with connectivity issues.
Stereo and Home Theater Speaker Kits
Some speaker manufacturers create kits of speakers that are designed for stereo and home-theater applications. It helps take the guesswork out of buying matched speakers for your component system, especially when dealing with surround sound.
Most of these systems contain 2 or 5 very small speaker cabinets, each containing 1 or 2 drivers (depending on manufacturer and model). These are designed to cover the high and mid-range frequencies. They usually come with a bass driver that may cover the range of a woofer and subwoofer.
Among the manufacturers that make these kits, the Bose Acoustimass series is among the most popular.
A Speaker Stand is a little platform that allows a (bookshelf) speaker to be placed on the floor without sounding boomy or causing the floor to vibrate. Most larger (floor-standing) speakers may benefit from a low speaker stand as well.
How and where speakers are placed in a room can effect overall sound output. Placing speakers close to walls and corners will increase their bass output; moving them away from walls and corners decreases their bass output. Speakers should have their tweeters as close to ear-level as possible depending whether you listen while standing or sitting. Rooms with carpeting and upholstered furniture may soften the sound whereas rooms with wood floors and wood furniture may brighten the sound. Adding an equalizer or adjusting tone controls on your component receiver may help compensate for these variances. This is a matter of consideration when purchasing speaker systems.
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