Talisman Designs SE Reference Tower - Manual (Page 7)

7
Avoiding Damage
Audio Concepts, Inc. speakers are designed for the purpose of accurate reproduction of music in the home.
We do our best to make our speakers rugged and reliable. However, ANY speaker or system may be
damaged under certain conditions:
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Excessive power, particularly at certain frequencies or for prolonged periods of time.
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Excessive distortion often caused by under-powered amplifiers or receivers.
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Defective amplification.
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Excessive subsonic energy.
Our systems are tested at high volume levels with a variety of amplifiers and receivers before a design is
approved. With many years of testing, we know it is virtually impossible to damage a component without the
system first giving audible warning in the form of distortion. We also know that true factory defects are
extremely rare, less than one in 10,000 drivers. Here are some considerations to keep in mind to avoid
damaging your drivers:
1. Even though a system may be rated for 100 watts or more it is very easy to damage it with a low
power receiver. When an amplifier runs out of power, it “clips”. This clipping produces large amounts
of distortion that sends excessive energy particularly to the midrange and tweeter. This clipping
distortion accounts for more than 80% of all tweeter failures. How do you know if the amplifier is
clipping? Volume knob placement does NOT indicate much. Some receivers reach full output well
before 12:00 on the dial. Use of the loudness button, bass boost and treble boost can all drive the
receiver and then the speaker into distortion at fairly low levels.
2. Many of today’s recordings including CDs and DVDs contain extremely powerful low bass. This low
bass can easily drive woofers into over-excursion or cause the amplifier to run out of power and clip,
causing tweeter or midrange damage.
3. Our systems are designed for accurate sound. Our rate of damage or failure is extremely low. We
could make the systems even more rugged if we were to compromise sound quality. Moving the
crossover points upward would protect midrange and tweeters better while causing a loss of detail,
clarity and imaging. The Talisman SE could have been designed to more rapidly roll-off the low bass
which would protect the woofers but this would lessen the low bass response and clarity. Protection
devices could be added in the crossovers, which would shut the system down when damaging power
or distortion was present but every one of these devices audibly degrades the sound!
You can protect your speakers by following a couple of very simple guidelines:
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If it sounds at all distorted, turn it down. Distortion is a warning sign that should not be ignored.
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Use tone controls with caution. IF you must use equalizers, monitor the system carefully.
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Beware the party damage epidemic. Speakers are more often damaged during parties. All those
bodies soak up sound, requiring more output to sound as loud, bass and treble controls are
sometimes cranked up and nobody is listening for distortion!
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Watch out for energy put out by the amplifier in the range below 20Hz, which is not music. Examples
include record warps, DC current and subsonic noise in the recording. These signals can take up a lot
of amplifier power which means the amplifier runs out of steam very early. These signals can also
overload a speaker even though you can’t hear them. If you have ever watched a cone “flap” you
know just what we mean.
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Vented speakers are particularly sensitive to signals below their F3 point. The average vented box that
can handle 100 watts at 50Hz may handle less than 5-10 watts below 25Hz! Sealed box speakers with
low Qts. numbers have a similar characteristic although not as severe. Low organ or synthesizer notes
may cause an otherwise excellent woofer to bottom out at relatively low input levels.
•
Keep an eye out for excessive cone movement that is not producing music. Find the source of the
problem and eliminate it, play at low levels, or use a subsonic filter (usually in your pre-amp) which will
filter out energy below 20Hz. However, use of a subsonic filter may take away from the naturalness of
bass sounds. We don’t recommend it for extremely critical listening.
•
In over twenty-eight years of daily evaluation of all types of speakers on everything from 10 to 1000
watts and with all kinds of music, we have never damaged a driver without first hearing audible
distortion. If it sounds bad, turn it down and you will never damage a speaker.