2015 Mondo Stereo Build

[David Analog]

Existing 4 X 10-inch subs are in a sealed enclosure, correct?
New 15-inch subwoofer in a sealed or ported enclosure?

[BrettLee3232]

Existing 4 X 10-inch subs are in a sealed enclosure, correct?
New 15-inch subwoofer in a sealed or ported enclosure?

Correct.

15" will be ported.


Sent from my iPhone using Tapatalk

[David Analog]

Correct.
15" will be ported.
Sent from my iPhone using Tapatalk

Then you will have multiple phase responses at the same frequencies.

[trayson]

As is I have 2400watts & will be 3600 when I add the 15".

I'm not sure the magical number either but when he did my stereo he had it on for 8+ hours about 75% and no issue. I've also ran about 7hrs straight with no issue.


Sent from my iPhone using Tapatalk

I'm finding this formula, which would say that at full tilt you'd drain your battery in under an hour...

Music With The Engine Off

If your only concern is listening to the music while the engine is not running, then you can calculate the current draw of the new stereo and estimate approximately how long the battery will last. In most instances this can be calculated using the following formula:

10 x (Battery Capacity in Amp Hours) / (Load Power in Watts) = Run Time in Hours

Let's look at an example. If you had a 500 watt amplifier and an Optima YellowTop® battery with a Ah rating (amp hours) of 75, using our formula above we can calculate a run time of 1.5 hours with the engine off (750/500 = 1.5 hours).

[BrettLee3232]

I'm finding this formula, which would say that at full tilt you'd drain your battery in under an hour...

So as of right now I'm suppose to have 0.416 hr? Maybe my math is wrong but 10 x 100 = 1000 / 2400 = 0.416

Doesn't seem right cause I've personally had it on for over 7+hrs near full volume.


Sent from my iPhone using Tapatalk

[KG's Supra24]

On the denominator, don't you have to divide your rated wattage by voltage? ........ 2400/12v or 2400/14.4v ... so that would leave 1000/200 @ 12v = 5 hours on the old system? New one being 3600/12 = 1000/300 = 3.333 hours?

Again ... I'm not sure if thats the magic formula or not

If you take the wattage output number (500 in the example) ... almost everyone will reflect less than 1 hour playtime.

[trayson]

So as of right now I'm suppose to have 0.416 hr? Maybe my math is wrong but 10 x 100 = 1000 / 2400 = 0.416

Doesn't seem right cause I've personally had it on for over 7+hrs near full volume.


Sent from my iPhone using Tapatalk

Well, I'm sure your system isn't going to be consuming the FULL 2400 watts. Music is dynamic to the wattage is going to vary with every note of the music. That said, I am surprised that you're getting that kind of run time off a single battery. I have about the same RMS wattage as you do (I'm taking my RMS rating at 12v not 14v), running 4 class D amps and after an hour or two I'll start to get clipping on my sub amp as it's running out of voltage from the batteries. And I have a pair of 105 Amp Hour batteries.

I'd imagine Dusty was wondering the same thing... How you're getting that kind of run time from just the one battery... Does your stereo run on magic beans? LOL

[trayson]

On the denominator, don't you have to divide your rated wattage by voltage? ........ 2400/12v or 2400/14.4v ... so that would leave 1000/200 @ 12v = 5 hours on the old system? New one being 3600/12 = 1000/300 = 3.333 hours?

Again ... I'm not sure if thats the magic formula or not

If you take the wattage output number (500 in the example) ... almost everyone will reflect less than 1 hour playtime.

amp = watt / volt

so in theory a 2400 watt system @ 12v = 200 amps. but we all know it's not going to pull the 200 amps continuously. what it if only pulled 1/4 of that on a continuous basis? so that'd be 50 amps.

My batteries are each rated for 105 AmpHours at a 20 amp draw. so with a higher than 20 amp draw, of course I'm not going to see 210 hours.

This would be a great time for the audio gurus to chime in and help us all understand how the RMS wattage of a system relates to the Amp Hour capacity of your batteries in real world boating applications...

[MLA]

Does your stereo run on magic beans?

Magic Kicker Beans

Even with the best of specs, run time is an estimated guess at best. You need to calculate the wattage based on how the amp chnls are loaded, rather than using the marketing numbers. Lets say you have a "1000W" amp, but only run each chnl at 4 ohm. In reality, you are likely seeing a fraction of that advertised number. Further, you cant really apply ohms law when one part of the equation is in AC and the other is in DC. As example, dividing 2400W output by battery DC.

The most accurate, and its still an estimate, is to determine the amps' DC current draw and use that with the battery bank Ah. to determine reserve.

[KG's Supra24]

The most accurate, and its still an estimate, is to determine the amps' DC current draw and use that with the battery bank Ah. to determine reserve.

I was curious about this ... as using the rated wattage to speakers doesn't factor in efficiency of the amp. 'Cause let's be honest, I've always known my WS amps are better than Dusty's exile were and certainly better than the PPI's