Difference between revisions of "Bridge Subwoofers"

#Locate the specification labels for your system. Your amp should have a label near the speaker output jack that indicates the output power (measured in Watts) and the minimum impedance (measured in Ohms). Be sure that your use the values for bridged mode, it is usually double the minimum impedance as stereo mode (meaning you need a much high impedance to run a bridged system) and up to four times the power output.<ref name="rf1">http://www.caraudioforum.com/showthread.php?t=97288</ref> Your sub-woofers should also be labeled with an impedance value (in Ohms) and a value indicating the maximum power input that they can handle (in Watts).<ref name="rf2">http://www.gollihurmusic.com/faq/31-OHMS_AND_IMPEDANCE_FROM_THE_OUTPUT_SPEAKER_PERSPECTIVE.html</ref>

#*The majority of amps on the home theater market are only stable at 4 ohms when bridged. Most car stereo amplifiers can do 2 ohms.<ref name="rf3">http://knowledge.sonicelectronix.com/car-audio-and-video/car-amplifiers/how-to-bridge-an-amplifier/</ref>

#Calculate the total impedance of all of your speakers. To do this you should add together the speaker impedance number for all of your speakers. You want the impedance to be at least equal to the minimum impedance value of your amp on each channel, but not to exceed 16 Ohms unless your amp is specifically rated for impedance values above 16 Ohms.<ref name="rf4"> http://cie-wc.edu/Series_Parallel_9_14.pdf</ref>

#Calculate the power each speaker will receive. This will be based upon the total impedance and the power output of your amplifier. You can use variations of Ohm’s Law to do the calculations yourself<ref name="rf4" /> or you can refer to the online calculator above. You do not want to overpower and blow your speakers.

#Verify that your amp has enough power for your subs. The output power should be stamped near the output jack on your amplifier and measured in Watts. You speakers should also be labeled with a wattage. The output wattage should meet or exceed the sum of all of your speakers. For example if you have two subs that each pull 200 W, you would want an amp that produces a minimum of 400 W. Ideally you would have an amp that produces more than what is required, this is referred to as "head room" and helps to avoid clipping.<ref name="rf5">http://blog.qualitymobilevideo.com/subwoofer-impedance-and-amplifier-output/</ref>

#Get a roll of stereo wire. You will need this wire to make the connections from your amplifier to your sub-woofers.<ref name="rf6">http://www.crutchfield.com/S-41nlFnQ6MAT/learn/learningcenter/car/subwoofers_wiring.html</ref>

#Connect the two coils. Just like wiring two separate speakers, the two coils within your DVC can be wired in series (increasing the sub's impedance) or in parallel (decreasing the sub's impedance).<ref name="rf5" />

#Wire the second subwoofer to the first subwoofer. Again, you have the series verses parallel debate.<ref name="rf5" />

#Connect the second sub's coils. Follow the same guidelines as when you connected the first sub's coils.<ref name="rf5" />

#Listen for inconsistencies. Power up your system and test it out. Start at a low volume and then slowly increase it to listen for anything that doesn’t sound right, like static or a difference in volume between the two subwoofers. If the bass and sub-bass are quiet or not present at all, something is mis-wired.<ref name="rf7"> http://www.caraudiohelp.com/newsletter/wiring_subwoofers_correctly.html</ref>