Car Stereos: have the power, now the sub., dual voice coil, sony head unit

Question
brian,

i  am currently running Alpine R 6" splits in front doors and alpine S 4" in rear. these are running from a $200 sony head unit.
I have just picked up an Alpine MRP-F600 and plan to run the splits and a 10" sub through through this.
Can you recommend some parameters i should be looking for when shopping for a sub for this particular amp? Alternatively, can you recommend any particular brands/models?
The sub will be installed in a custom enclosure.

Also, i have been told that sound deadening is a good idea to boost performance. what is your take on this? and what are the advantages?

thanks in advance

Answer
Hi Brett,

Sorry about the extreme delay in answering your question.

Your amplifier is rated for 300 watts RMS in bridged mode, but with a minimum impedance of 4 ohms.  This means you'll want to look for either a 4-ohm single voice coil subwoofer, or a 2-ohm dual voice coil model.  A dual 2-ohm sub can be wired with the coils in series to make a 4-ohm load for the amp.  Assuming you're looking for a single subwoofer, then you'll want to avoid the more common 4-ohm dual voice coil type; one of these could only be wired as a 2-ohm or 8-ohm load, and it wouldn't be a very good match for the amplifier.

You'll probably have an easier time finding a dual voice coil sub that's rated for at least 300 watts RMS, than a single voice coil model with this kind of power handling (though there are a few out there).  I don't want to recommend a particular model, because I'm not sure what's available in your part of the world.  If you're planning a custom box to match your selected sub, though, then you're likely to get good results with just about any decent quality subwoofer.

Sound deadening, or damping material, can be pretty effective.  What damping material does is help prevent panels from vibrating.  It's especially useful when you're applying it around a speaker mounting position.  As a rule, if a speaker is inducing a vibration into a mounting surface, it's wasting energy--moving metal instead of moving air.  You can also use damping material to seal some of the gaps in the mounting surface, so that the output from the front of the speaker is completely isolated from the output created by the rear of the speaker; this also helps the sound quality.

Hope this helps!

Brian