C7-sERIES
SUBWOOFER MANUAL
Thanks for buying our product!
Product information follows; please read it carefully to get the most out of your
subwoofers. Any questions, you can contact technical support:
Phone 972-570-0800; Email: tech@crossfirecaraudio.com
Enjoy!
Subwoofer Power Rating:
Power handling for subwoofers depends on the conditions used. How loudly you play, what type of music and how hard
you drive the amplifier are more important than any numbers-but of course, some kind of numeric guideline is necessary for
convenience. Therefore, Crossfire rates as follows:
Nominal Power Handling:
This amount of RMS amplifier power should not cause damage to a subwoofer in a
recommended enclosure-so long as the amplifier is not clipped.*
Maximum Power Handling:
This amount of RMS amplifier power driving the subwoofer at maximum volume continuously
could cause damage over time and should be used with caution and without clipping the amp.
Notes On Amplifier Power:
The important rating of an amp is RMS power. If this spec is not exaggerated, it is how many watts the amp can output
continuously without distortion. Other specs (“peak” ; “maximum”) are not very meaningful in most cases. How does this match a
subwoofer’s power rating? Read on...
Notes On Subwoofer Limits:
Subs have two limitations:
mechanical
and
thermal
. Crossfire combines these into the ratings explained at the top.
Thermal power handling
of the woofer is basically how many watts you can pump into it before it burns or melts:
-Amps’ RMS power similar to the subwoofers rating should a good match providing the amp is not clipped
-Amp’s RMS power much more than subwoofers rating: could damage the sub unless gains are carefully set to prevent the
amplifiers ever clipping.
-Amp’s RMS power much less than the subwoofers rating: could still damage the sub if the amp is clipped.
Mechanical power handling
means how far the cone can move before physical parts hit or deform (“bottoming out”). At very
low frequencies, it does not take much power to move the subwoofer cone a lot, so even low powered amplifiers could damage
the subwoofer. The enclosure affects how easy it is to hit the mechanical limits: please see notes on a later page.
*Amplifier Clipping and Dead Subwoofers:
When “Clipped” the amplifier tries to put out more power than it is capable of, and the output waveform flattens out, no longer
following the music. Viewed on an oscilloscope, it looks like the music waveform has had the tops “clipped off” with scissors.
Under these conditions, an amplifiers could put out over twice it’s rated RMS power, causing a subwoofer to overheat.
Additionally, a clipped amplifier can generate DC currents which will drive the subwoofers coil out of position: it may burn and/or
hit mechanical limits more easily. A clipping amp will sound highly distorted and crackly. A sub hitting it’s mechanical limits tends
to sound like a jackhammer or woodpecker. These sounds often indicate damage could be imminent.
- Bottom line? If it sounds not merely loud but nasty, TURN IT DOWN before something breaks!
