The Difference Between Stereo Speakers & Guitar Amp Speakersby David Lipscomb
Your home stereo speakers may sound great, pumping as much volume into your listening space as you can tolerate. That doesn't mean that they work well or for long when used to reproduce amplified guitars or other instruments. Pro-grade speakers used in large environments like concert halls and churches use dedicated speakers, much different that the ones in your living room. If you're comparing the two types to determine which to use where, there are key differences to consider.
Channels and Amplification
Home audio speakers, except in some esoteric audiophile applications, are typically stereo. This means each speaker reproduces a specific channel of sound, determined by the encoding on the CD or MP3 file. These connect to a receiver or amplifier, ideally operating within the wattage range of the speaker. With few exceptions, these speakers are passive, meaning they lack their own internal amplification. Guitar amp speakers are often powered, getting their signals via microphone cable direct from a mixing board or the guitar itself. These speakers are typically mono, or single-channel, since the guitar is one single source lacking stereo separation. For example, one guitar requires one amplified speaker, while a second musician playing a second guitar normally has his own. In some space-limited cases, the output from both guitars may be mixed to a single speaker.
Guitars operate within a certain frequency band for most of its sonic reproduction, typically 80 Hertz to 5 kilohertz or somewhere close to that. This means that while you could theoretically use a guitar speaker with your home stereo, you would have little if any true bass and limited high frequency reproduction. Stereo speakers for the home, if properly designed, are intended to reproduce the full 20 to 20,000 hertz frequency band, with few peaks or dips in response. In the audio world there are exceptions to every rule, but in most cases using a guitar amp or a pair of them as stereo speakers would yield uncomfortable or at the very least inaccurate sound.
Connectivity and Line Voltage
Connecting an amplified guitar speaker to a home theater or stereo amplifier may prove challenging. The majority of amplified or pro-audio guitar speakers use XLR or microphone jacks, the former being uncommon and the latter nearly impossible to find on home audio gear. Home stereo speakers typically use conventional speaker wire. In some cases, powered home speakers also use XLR or RCA line-in connections; however, these products "expect" to see typical home audio line voltage or 2 volts. Mixing boards and guitar preamplifiers routinely provide around 9 volts or more, potentially overloading inputs on conventional amplified home speakers.
Guitar speakers' limited frequency range means that high power is not normally required. Humans are very sensitive to the midrange and upper midrange octaves, exactly where guitars normally operate. Additionally, since guitar speakers are not tasked with reproducing power-sapping low bass and upper treble, the power handling needs are lower. As a result, some audio speakers intended for full-range use sometimes require 100 to 400 watts of power, while many if not most guitar speakers require 20 to 60 watts at most. Bass guitar speakers operating in the 50 to 80 hertz region typically have increased power handling in the 100 watt range. This requirement is primarily due to higher strain on the amplifier when reproducing lower frequencies, a task which in turn places increased demand on the connected speaker. Even if you can find a guitar speaker that operates in a conventional home audio power range, the factor of limited frequency response still remains, keeping these speakers best suited for stage use.
Cabinets and Aesthetics
Guitar speakers are designed for the road. This means rugged, utilitarian cabinets with metal corner protectors and open grilles. Home audio speakers, in addition to providing quality sound, often are intended to be at home with quality decor, using maple and gloss lacquer finishes. Cost typically increases with nicer finishes. Guitar speakers are likely to clash with your living room's style and your spouse's taste. Conversely, in addition to being sonically inappropriate, using home audio speakers on the road is an invitation to waste or destroy these nicer-looking products.