The SEVEN Value when calculating RMS:
The value used when calculating RMS (Vrms =Vp*) is .707.
.707 is typically for the sine wave only, and determined by taking the integral of V(t)2 over a full cycle, dividing by the time of the cycle, and then taking the square root of the answer (hence the name "root mean square", RMS).
Some quick facts about SEVEN products, materials, research, design & development:

-Manufactured dual voice coils @ 2ohm impedance with an outstanding "Mechanical Q" (QMS), such as 4.01. A lower Qms means tighter suspension (the spider and the surround working together).

-High Efficiency FEA optimized motors (Finite-Element-Analysis based optimization of structural mechanics in engineering). We also use the NEO motor system in research and design but have not released any NEO subwoofer models yet (if), because the market has not stabilized.

-High performance oversized double stitched foam (polymer infused) surround that sits one full inch tall; a stiff but light weight design.

-The only Ten Inch Subwoofer model we will ever make, the ss1000, was newly designed in 2016 using a Satin Black (powder coated) Die-Cast Aluminum Alloy Rigid Frame, with six flared out vents surrounding the spider and coil (six forced-air vents that each flare out). These vents together provide open air of 33 squared inches.

-Each ss1000 subwoofer has a supporting top plate three quarters of an inch solid allowing for the "Ten's" open air design. Notice in the pictures, six (6) four inch long rails surrounding the basket. This creates additional rigidity.

-The ss1000 uses the same 3" coil as the 12" model, the ss2000. It makes a tight fit, but also an impressive ten inch subwoofer that gets low.

-One of Seven's parts manufacturers designed and introduced the "Neodymium Magnetically Powered Motors" into subwoofers. This company has been in business over 20 years.

-In such a competitive market, a company should try to set its self apart with more than just a down hill price battle. Though not yet in full swing, multiple clothing lines using two different Seven logos is one technique we chose. Another thing is art work! We have fun with art and creative photography involving our logo and our products.

-Why speakers? Why not... people are passionate about music. Without speakers we would have no music in our vehicles. That is unless Mozart was riding shotgun or having Alexander Graham Bell cranking on a sound machine in the back seat. These modern days, we as people, have become a little crazy with music. Not just the songs, but the speakers them selves have sort of come to life; capable of performing "hair tricks" and floating hats! It's fun...

Understanding even the smallest differences in subwoofers unlocks the door to engineer a better sounding, better looking and more efficient product for our customers.

For example, here are specs on the only TEN inch subwoofer we need, the ss1000 (Ten inch High Performance Subwoofer by SEVEN):
fs/fms: 31.6hz
Qms: 4.01
Rms: 12.7 - kg/s
Nret: 0.16%
VAS: 15.1 L
RES: 180.9 ohm
Qes: 0.28
Cms: 0.10
Rp: 54.0 ohm
Le: 2.98 mH
Re: 4.0 ohm
Qts: 0.26
Mms 256.5gr
SPL: 84.1 dB
Lp: 77.6 mH
Below are specs on the white twelve inch subwoofer, the wss2000 (Twelve inch High Performance Subwoofer by SEVEN, white basket):. This speaker may be discontinued - TBD
fs/fms: 38hz
Qms: 4.931
Qes: 0.360
Cms: 68.451u M/N
Fo: 38.440 HZ
Sd: 51.071m
MMd: 198.000g
BL: 25.916 T
No: 0.387%
Krm: 70.176m ohm
Kxm: 206.028mH
ERM: 0.638
EXM: 0.544
Qts: 0.336
MMD: 280.244m kg
Mms 286.881g

           (3.5sf if underpowered)
Below are specs on the black twelve inch subwoofer, the ss2000 (Twelve inch High Performance Subwoofer by SEVEN, black basket):

fs/fms: 36.1hz
Qms: 3.51
Rms: 18.6 - kg/s
Nret: 0.23%
VAS: 19.3 L
RES: 137.3ohm
Bt: 23.4 N/A
Qes: 0.48
Cms: 0.06
Rp: 35.5 ohm
Le: 1.62 mH
Re: 4.0 ohm
Qts: 0.42
Mms 266.1gr
SPL: 85.7 dB
Lp: 42.1 mH
We maintain a high level of quality in our products, and strive to do the same with customer service. If you are experiencing any difficulty with one of your Seven products please use the following form to contact us.

Turn around times vary...
    Thank you for your understanding.
©2018 SEVEN, LLC  - ALL RIGHTS RESERVED,  Subwoofers | Car Audio and Apparel
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product in question:
Like small practical subwoofers? Neither do we... We have one however! Its the ss300 subwoofer (Six n' half inch Subwoofer by SEVEN):
fs/fms: 66.4hz
Qms: 5.93
Rms: 5.0 - kg/s
Nret: 0.15%
VAS: 2.3 L
RES: 69.2 ohm
Qes: 0.43
Cms: 0.08
BL: 16.6
Rp: 41.1 ohm
Le: 1.69 mH
Re: 4.0 ohm
Qts: 0.40
Mms 70.8gr
SPL: 83.9 dB
Lp: 28.5 mH
Here ( --> ) are two proven enclosure design options for two Seven twelve's. The top one, non-slot port design, produces a 151.7db when built correctly and when given enough power. The 151.7 was done on a SoundQubed 6k amp, using two batteries and an upgraded alternator in a Jeep Grand Cherokee. He has taken home several trophies!
Click for specs on the ss5500
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