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how to find box rise


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Here is a good example. This is a frequency plot of a woofer in FREEAIR.

b707fe5e.jpg

Let's say I hook up my amp to this woofer sitting on my kitchen table and I play around 42 Hz. Looks like I am going to see a calculated impedance of ~40 ohms on an 8 ohm woofer. Guess I will just call that "table rise". . .

Current system:

1997 Blazer - (4) Customer Fi NEO subs with (8) American Bass Elite 2800.1s

Previous systems:

2000 Suburban - (4) BTL 15's and (4) IA 40.1's = 157.7 dB at 37 Hz.

1992 Astro Van - (6) BTL 15's and (6) IA 40.1's = 159.7 dB at 43 Hz.

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Best info you can get right here to do it in english. As long as you have the right meters and know how to use them :peepwall:

http://www.stevemeadedesigns.com/board/topic/23462-check-actual-ouput-of-an-amplifier/

And I just made this sheet up in excel since it takes me two seconds and I will actually be able to read part of what I right but this is the type of chart you make to do the math on

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ac voltage x ac amperage will be how much power

ac voltage / ac amperage is the your ohm load....

if you are doing just straight burps...

The DC Integra 3 18s to 6 15 build log

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where theres a will theres a wall.......

I just realized Steve has reach Voldemort status, over on JP's site he is the one who will not be named....."We dont speak his name over here, fearing it will destroy us" LOL not even in hush tones

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ac voltage x ac amperage will be how much power

ac voltage / ac amperage is the your ohm load....

if you are doing just straight burps...

this is more to my level and im sry if i annoy u skittles phfffff i am meeting up with rusty and he is going to show me how , what up dave how ya been

Team SSBTeam SoundStreamTeam Tsunamiteam ohio generator

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maybe i should hav asked for the idiot guide way lmao, but i saw no need for someone who sees someone at all his shows to try and insult them ( skittles) so if its like that bro then it will be that im sry i aint a genious wat i meant was that page read like german to me

Team SSBTeam SoundStreamTeam Tsunamiteam ohio generator

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Volts / amps = ohms

Volts x volts / ohms = wattage.

2008 California state record holder 157.2 Bassrace2009 California state record holder 157.0 BassraceRollin 50's 158.7db2009 King of Cali Bassrace2009 USACi score 160.5 @ 42hz
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Volts / amps = ohms

Volts x volts / ohms = wattage.

Looks familiar to what I txt him yesterday ;)

It's ok Timmy, we will get you up to speed one of these days good.gif

Designing, building, and shipping boxes. Yahoo IM - kingsuv00If the listening level is too loud, please inform the driver, so he can promptly pull over, and let you out.

not many cars can get me to pluggin my ears but this one.......damn. I mean the first minute is ok but that thing just really starts digging deeper and deeper in your earhole till you cant stand it no more. Seems like it does it with relative ease....16 12's on 8 amps.........gotta love it. :)

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Need a ac amp clamp and a multimeter.

Ac amp clanp goes around the pos spkr wire.

Meter gets set to ac voltage, probed into the spkr leads.

If its a burp car, or if you just care about rise at your peak freq, just play that tone.

I use my phone and shoot a video of the run.

Then just go back and pause when you are at full tilt.

For instance..

We just clamped in the crx.

Single dd1508

S4 coil

Alpine mrp2000 amp

Battery v dropped to 13.1

37hz tone

Got 99.3volts ac on the spkr leads

Got 10.3 amps on the pos spkr wire

So..

99.3 / 10.3 = ohms

Then 99.3 x 99.3 / ohms = clamped powaaaa

2008 California state record holder 157.2 Bassrace2009 California state record holder 157.0 BassraceRollin 50's 158.7db2009 King of Cali Bassrace2009 USACi score 160.5 @ 42hz
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ac voltage x ac amperage will be how much power

ac voltage / ac amperage is the your ohm load....

if you are doing just straight burps...

This explains why you come up with different numbers than I do..

Sukka

2008 California state record holder 157.2 Bassrace2009 California state record holder 157.0 BassraceRollin 50's 158.7db2009 King of Cali Bassrace2009 USACi score 160.5 @ 42hz
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