We GoldenEar folks collectively have been involved in the audio business since 1968. In that time there's one uninitiated consumer question that has remained consistent; "How many watts does that 

speaker have?" If you're reading this newsletter we assume you understand that speakers don't have watts. (Well, actually, some speakers like our powered Triton towers DO have watts, but that's a different story.) But speakers need watts to make sound and just about every decent passive speaker on the market lists a recommended wattage range. A dirty little secret within the industry is the fact that many of those ratings are, to be kind, somewhat fictional at best. So how important are speaker wattage ratings and how many watts do you really need?

The vast majority of residential speaker systems can be driven to produce sound with an average power level as little as 1 watt. It's generally agreed that the average power levels used while listening to music domestically range between 1 and 10 watts. However, musical peaks and crescendos, not to mention cinema special effects, can ask for upwards of 500 watts, depending on the speaker's sensitivity, its impedance, your listening level and the dynamic range of the source material. Determining your wattage needs should start with the sensitivity of your speakers. Unfortunately, there are often differences in the methods used by manufacturers to determine speaker sensitivity so it can be hard to make direct comparisons. That being said, the vast majority of speaker systems on the market range between 80 and 93 dB output, measured at one meter distance, when driven by a 2.83-volt input (which translates into 1 watt into an 8 Ohm speaker load).

What's a dB?

From (Wikipedia, 1/15): "The decibel (dB) is a logarithmic (see figure below) unit used to express the ratio between two values of a physical quantity, often power or intensity. One of these quantities is often a reference value, and in this case the decibel can be used to express the absolute level of the physical quantity, as in the case of sound pressure... One decibel is one tenth of one Bel, named in honor of Alexander Graham Bell. The Bel is seldom used without the prefix...A change in power by a factor of 10 corresponds to a 10 dB change in level. A change in power by a factor of two approximately corresponds to a 3 dB change. A change in voltage by a factor of 10 results in a change in power by a factor of 100 and corresponds to a 20 dB change. A change in voltage ratio by a factor of two approximately corresponds to a 6 dB change.." The "B" in dB is capitalized because it represents Bell's name.

The upper scale is logarithmic, the lower scale is linear.

A change of 3 dB in volume is just noticeable to most people. Making midrange or high frequency sounds twice or half as loud requires a power change of 10 dB. To accomplish the same increase or decrease in the bass demands a 6 dB power change. To make something 10 dB louder can require up to 100 times the power (because the dB scale is not linear but logarithmic). So it's fairly easy to see that cranking up the system for a party or listening to very dynamic sources with large peaks or crescendos can put significant power demands on amplifiers and speakers. Even though average levels may be only a few watts, dynamic levels can be dozens or even hundreds of watts, if the amp can deliver them. Beyond all that, the actual impedance of the speakers varies based upon the frequencies it's reproducing at any given moment and that will impact the power demand from the amplifier as well. So how much power do you need? Read on.

"More power, Igor!" - Dr. Frankenstein (to the best of our knowledge not an audiophile. But he's got some pretty impressive equipment there.)

Having an amplifier capable of delivering more power than the minimum required will generally result in more dynamic capability, lower distortion, and better "control" of the speaker's drivers. We're assuming here that the amplifier is a high quality unit with good sonic performance. Since the most demanding part of the frequency spectrum power wise is the bass, GoldenEar offers several models with active, powered subwoofer sections relieving the system amplifier of the bass burden. Even so, having a good power reserve just for the mids and highs will result in better overall acoustic performance. So extra power, as long as it's of good quality and used carefully, is a good thing.

Keep the Clipping in the Barber Shop

No matter how much power your amplifier can deliver potential speaker damage is a fact of life in audio systems. It's easy to understand how simply pumping huge amounts of power into a speaker can damage it but how about damage from too little power? How can that cause problems? When you're listening at average levels of a few watts and a substantial peak or series of peaks comes along it can create a demand for much more power as detailed above. If the amplifier's not capable of meeting the demand, its internal power supply (that feeds all its circuits) can run out of reserve.  If the demand continues, the amplifier and power supply essentially lock into a sort of full power output loop mode. The resulting over-driven output is substantially distorted and this is commonly called "amplifier clipping".

The clipping distortion contains lots of high frequency energy that particularly taxes the speaker's tweeter driver. Since most tweeters are delicate, low power handling devices they're usually the driver that's damaged first. Left unchecked, running the amplifier out of power like this can eventually damage midrange and woofer drivers too. Worse still, this kind of damage is cumulative, so the damage from short periods of amplifier clipping can eventually build up, resulting in permanent speaker damage. If the affected driver isn't completely broken you may hear "scratchy" sounding distortion from the speaker as the affected driver's voice coil, which has expanded from the heat generated by the distorted high power input, rubs within its magnetic assembly. The advanced GoldenEar Folded Ribbon tweeter is much less prone to this type of damage because it doesn't have a voice coil like most tweeters and therefore can handle significant amounts of power. But given enough abuse any driver can eventually be damaged.

Listening to jazz, country, soft rock or other "quieter" music makes clipping distortion relatively easy to hear because this content usually involves natural instruments, distinct voices and other easy to discern sounds. Classical symphony orchestra recordings, can be more difficult because of the complex nature of their sound. Hard rock, complex hip-hop, and many movie soundtracks are so busy that even substantial clipping can be hard to discern.

What's Up with Your Watts? (And How Loud is Too Loud?)

We would generally recommend amplifiers delivering 50 to 100 "clean" watts per channel for most GoldenEar speakers in residential applications. Since the larger GoldenEar Triton models have powered bass sections your amplifier will only be driving the midrange and tweeter sections, which reduces the power demands greatly thus letting your amplifier perform like a much more powerful unit. Still, when you're using any GoldenEar speaker you'll get the best performance by using the highest quality amplifier you can. Since this can be a synergistic pairing, your GoldenEar dealer will have set up systems in their store for you to evaluate that are appropriate and great sounding combinations.

You'd be better served using a judiciously controlled high power amplifier than using a low powered amp to avoid the risk of speaker damage. Then the question becomes how do you know when to back off on the volume control? Ahhh, that's the $64,000 question as they say. We suppose that the best simple answer is to use common sense at all times, remembering that your home audio was never designed to be a commercial sound reinforcement system. Your first concern should be long term hearing damage from listening at high volume levels. The relevant information below was gleaned from www.dangerousdecibels.org, a non-profit organization founded to educate the public about protecting their hearing:

"Sound pressure is measured in decibels (dB). Like a temperature scale, the decibel scale goes below zero. The average person can hear sounds down to about 0 dB, the level of rustling leaves. Some people with very good hearing can hear sounds down to -15 dB. If a sound reaches 85 dB or stronger, it can cause permanent damage to your hearing. The amount of time you listen to a sound affects how much damage it will cause. The quieter the sound, the longer you can listen to it safely. If the sound is very quiet, it will not cause damage even if you listen to it for a very long time; however, exposure to some common sounds can cause permanent damage. With extended exposure, noises that reach a decibel level of 85 can cause permanent damage to the hair cells in the inner ear, leading to hearing loss. Many common sounds may be louder than you think...

• A typical conversation occurs at 60 dB - not loud enough to cause damage.
• A bulldozer that is idling (note that this is idling, not actively bulldozing) is loud enough at 85 dB that it can cause permanent damage after only 1 work day (8 hours).
• When listening to a personal music system with stock earphones at a maximum volume, the sound generated can reach a level of over 100 dBA, loud enough to begin causing permanent damage after just 15 minutes per day!
• A clap of thunder from a nearby storm (120 dB) or a gunshot (140-190 dB, depending on weapon), can both cause immediate damage."

You can check how loud you're playing your system with a SPL (Sound Pressure Level) meter or app for your smartphone or tablet. Here's a link to a non-partisan article concerning reviews of some available smartphone apps: http://blogs.cdc.gov/niosh-science-blog/2014/04/09/sound-apps/.

Where the volume control is set doesn't necessarily tell you how loud a system is playing. As a general guideline keep volume levels as reasonable as possible. Interestingly, our experience has led us to the conclusion that there seems to be a "just right" level for most recordings at which the music "blooms" with good bass impact, midrange clarity and high frequency definition. When you're listening, try to find that level but make sure it's not excessively loud. Remember, it's not just how loud it is, it's also how long you listen at high levels that can impact your hearing. It is also common for people to become accustomed to any given volume level after listening for a while and then to raise the level.  This is particularly true while driving, leading to people getting into their cars in the morning, turning them on and getting blasted by the stereo as it was set the night before.  So be aware of your listening volume at all times. Your ears and your speakers depend on it.