4 ohm woofer suggestions/info!!

i would like to use a 12" 4 Ohm free air woofer or a woofer requiring a small box volume - to connect to a 350 W RMS plate sub amp - to be installed in a digital portable jobsite boom box
an ipod will send the signal & another amp will power the 2 Bose cubes mounted for the highs & mids

any info/suggestions/reply on such a woofer will be much appreciated

i already built a digital portable jobsite boom box made of plexiglass w/ an ipod for the signal, a Bose sub plate amp powering a 12" Pioneer woofer, & a DJ rack amp mounted on top of the boom box - fed into a low band blocking crossover - powering 2 Bose cubes (from a surround sound set)

the first prototype is pretty & sounds great - loud & clear, but large, heavy & not up to my standards

i have pics if interested in getting some emailed to check it out

any reply will be much appreciated/anticipated


Disabled Account
2002-12-22 2:13 am
Calgary, Alberta
Well, you didn't say why you pre-specified 12" and 4 ohms, and you don't say what was wrong with the 12" sub you already made other than it was heavy, and you don't say what amp power you have (EDIT: oops, you did), sound levels you are looking for, or what bass extension you are looking for. Not a lot of info to go on.

In general, if you want a sub with a small box and don't want to use EQ, you are looking for a driver with a low Fs and low Qts.
im looking for a woofer that will be installed in a portable digital boom box:

I've already built 1, but it is too large, heavy, & not up to my standards (pics are available to be emailed if requested)

the boom box will receive the music signal from a MP3 player, a 2 channel amp will provide the highs & lows to 2 Bose Cubes & a 350 W RMS @ 4 Ohm plate sub amp will feed the woofer

desired woofer should mirror the following specs:
12" circumference (my desired size- i guess i think it will sound best?)
4 Ohm Impedence (provides for the highest power rating from amp that will be used)
Handle 350 W RMS (specs of amp at 4 Ohm)

I would like a woofer which will provide good bass/sound for pop/rock type music played medium to loud volume

I would like the woofer to be a free air woofer, or 1 that requires a small enclosure volume, as I would like to keep the boom box as small as possible, but still sound awesome (it will already contain 2 amps, 2 Bose Cubes, speaker plugs, possible crossovers, etc.

other than the above info. - i really dont know that much about electronics, audio products, etc.

any info/suggestions/reply will be much appreciated
Hi Eric,

If you are using Bose cubes there will be a gap between where those go down (250 Hz?) and what the plate amp delivers to the woofer (max 150 Hz?). I wouldn't spend a lot on the woofer if that's the case. Have a look at Parts Express. I believe their house brand 'Dayton' will meet your needs.

Oh and don't worry about the 4 or 8 ohm. It's only a 3 dB difference.

EDIT: Think sealed box for protection and as leadbelly mentioned a low Qts that can handle a small box.
im using the plate amp described above for the woofer only

im researching another plate amp or a small amp which can be installed inside the boombox to power the Bose Cubes

my first prototype has a rack-style DJ amp powering the cubes which is too large & ugly

im looking for a free air (requiring no enclosure) or a small-volume-enclosure-required woofer

trying to keep the boombox small
Since you want a small speaker box...........

A Sony Xplod XSL121P5W woofer would work good.
350W RMS 1200W MAX
I have the older XSL120P5W (same woofer, different color)

It's designed for small, sealed enclosures. Frequency response rated at 20hz in a 1cu ft box (I like to use 1.25cu ft to go deeper :D )

Now even though the woofer plays low, it still has good upper-mid bass, and for your application with the small Bose Speakers, you may not need to filer the sub much.

The cone, surround, and dual spiders are rock solid - you are more likely to burn the coil before ever damaging the other parts of the speaker. Also, the lead wires are run between the dual spiders, so they don't break from excursion like many other woofers do.

And they are cheap, just under 70.00 for one.

If you want even a smaller box with good bass, you can get the 10 inch version instead.