Subwoofer Q's

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I am looking at adding a subwoofer. I have been looking online...and not quite sure what I am looking at. As far as brand, I will stick with Polk since I have already purhased new 650db's. In the description, some subs just say " 4-ohm subwoofer" and others say "subwoofer with dual 4-ohm voice coils". What is the difference?

 

[Bottom Line]

Anyone????

 

[Kendall]

I am looking at adding a subwoofer. I have been looking online...and not quite sure what I am looking at. As far as brand, I will stick with Polk since I have already purhased new 650db's. In the description, some subs just say " 4-ohm subwoofer" and others say "subwoofer with dual 4-ohm voice coils". What is the difference?

The dual 4 ohm voice coils allow you to bridge a single channel amplifier down to 2 ohms. Make sure you get an amplifier that can handle this and it will be awesome.

I recommend JL Audio amplifiers.

 

[SeaRay]

The dual voice coil can be wired in parallel or series for either half or double the rated resistance. So the dual 4 ohm coils will be either 8 or 2 ohms depending on how you wire it. As mentioned you need the correct amp to run the sub.

I am in the process of putting a Wetsounds 12" sub in my boat. I was working on installing an Alpine 10" marine SWR M100 sub but it wasn't working out for me because I did not have enough space for it.

I am very happy with the the Wetsounds sub, they also make a 10" sub. I have heard the JL Audio 10" subs and they are nice as well. But, I understand they are more of a power hog.

I don't think the Polk Audio sub is as highly rated. I also have the DB651's in the boat and on my wakeboard tower but went with the Wetsounds as they are very highly rated as marine subs.

I learned the hard way, place close attention to the enclosure size you need and whether the sub is "Free-Air" or an "infinite baffle" type of sub. These subs do not have to be in a box but sound better if they are. The Alpine needed a 4.85 cu ft box. The Wetsounds sub I bought needs a .9 cu ft box.

Post away or shoot me a PM. I am in the process of the finishing touches of my sub box as I type and I learned a TON about subs over the last 2 months.

 

[HIFI]

Just a suggestion . . .

Take a look at what the subwoofer manufacture recommends for cabinet enclosure. Many manufactures give detailed drawings for each driver they offer for sale. They have spent far more in research and development than we could. They likely have it correct on cabinet dimensions for their Subwoofer.

If you don’t mind a little more work a ported design or vented design can give tremendous results. You don't have to be an engineer either. Many companies offer drawings and specifications for that type of enclosure.

A good woofer in a proper tuned box can produce better sound than a great woofer in a poor box.

 

[lorenbennett]

Know for a little techno jargin. Duel voice coils were developed for more accurate response. Due to the nature of speakers wanting to flutter and the limited travel range of a speaker they added a second winding thus allowing more accurate responce along with lower power requirements (when needed) As was mentioned there are other benifits also such as wiring for different ohm's. Remeber never run both coils in paralel unless you are feeding it with a sub signal. While sub channels are mono, standard output of mids and highs are in sterio and not always the same info and will cause over heating in the amp due to the speaker fighting it self and can actually lead to lower volumes due to cancelling it self out. Just for fun test on a bench and turn up a nrmal stereo, then switch the wires on one speaker and notice that the volume lowers. Have fun!:thumbsup:

 

[Sublimetime]

The purpose of a dual voice coil is so you can use one single subwoofer speaker -in an enclosure or mounting area(usually when limited space is available) and you can then wire it to both channels--one voice coil handles the left signal and the other voice coil handles the right signal.
Since low pass bass sound is omni-directional(unlike your tweeters which are very directional-easy to locate) its ok to have both the left and right coming from the same place. Most home theatres are set up like this.

 

[beachcombersc]

The purpose of a dual voice coil is so you can use one single subwoofer speaker -in an enclosure or mounting area(usually when limited space is available) and you can then wire it to both channels--one voice coil handles the left signal and the other voice coil handles the right signal.

Sorry, Not correct...

Know for a little techno jargin. Duel voice coils were developed for more accurate response. Due to the nature of speakers wanting to flutter and the limited travel range of a speaker they added a second winding thus allowing more accurate responce along with lower power requirements (when needed) As was mentioned there are other benifits also such as wiring for different ohm's. Remeber never run both coils in paralel unless you are feeding it with a sub signal. While sub channels are mono, standard output of mids and highs are in sterio and not always the same info and will cause over heating in the amp due to the speaker fighting it self and can actually lead to lower volumes due to cancelling it self out. Just for fun test on a bench and turn up a nrmal stereo, then switch the wires on one speaker and notice that the volume lowers. Have fun!:thumbsup:

This is the reason....

Good luck!!

 

[KayKook]

Check out the new RSX Sub's that Treo introduced at CES this past January. Very nice stuff.
"
They will be available in 10-inch and 12-inch sizes, both featuring dual 2-ohm or dual 4-ohm voice coils. The subwoofers feature a large diameter motor structure that delivers precision cone control along with the shallow mounting depth required for many challenging applications. Four-layer 2-inch diameter voice coils, innovative poly-paper hybrid cone materials, and advanced construction techniques allow power handling of 400 watts RMS. Suggested retail prices range from $149 to $199."

http://www.treoonline.com/

 

[HIFI]

Purpose for Dual Vioce Coil Driver

The first designs and purpose for a Dual Voice Coil driver was in commercial application.
Studios and sound stages were using dual voice coil drivers for the purpose of providing more power to a single driver. It is the quantity and quality of power that will make a driver sound better, not the number of voice coils.


"Dual voice coil driver has more accurate response" . . . that may not be an accurate statement.

A single VC woofer with great power will always outperform a dual VC woofer with average power. This is assuming same brand/quality driver and cabinet design.


In the late 70's and early 80's Fosgate took the dual voice coil technology to the auto market. Once again it was not the two coils in one driver that made it sound better. It was simply providing more Fosgate power to the driver that made it sound better. Power and control of the woofer lead to more impact and dynamic range. Fosgate also pioneered the amp bridging technology that is used today. But even then it was bridging two stereo channels to a single voice coil driver. Once again to put more power for better control and impact.

Jeff, I don't know if this helps you. I would still refer to manufacture for cabinet/enclosure specifications. All the tecno jargin goes out the window with the good bass if you miss on the enclosure.

 

[Bottom Line]

Thanks for all of the input...