Pulling more current at 55 hertz than 40 hertz?

[psych0ticnemes1 5,000+ posts]

Amp: Sundown SAZ-1500Dv.2

Sub: One 15" wired to 1 ohm (I'm positive)

Box: 5 cubes, 37 hertz or so (daily box, will change for competing)

Vehicle: Pontiac Vibe, resonant frequency around 55 hertz

I've been messing around with test tones because I plan to compete in the upcoming season, and for some reason my voltage tanks to about 13v @ 55 hertz but stays at 14v at 40 hertz. This seems backwards to me. Is it because I'm using a massive box tuned low? I should be loudest around 55 hertz with the proper box tuning.

Thanks guys.

-Psych0

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[T3mpest 10+ year member]

Impedence of a box rises near tuning. Thats partially why porting a box helps, it makes the box louder at that frequency, while also reducing the thermal issues at that frequency. So you should be pulling less current at near tuning as that's where impedence will be highest. If your trying to peak at 55, I'd tune around 50hz. Wont' sound good at all for daily though.

 

[psych0ticnemes1 5,000+ posts]

Impedence of a box rises near tuning. Thats partially why porting a box helps, it makes the box louder at that frequency, while also reducing the thermal issues at that frequency. So you should be pulling less current at near tuning as that's where impedence will be highest. If your trying to peak at 55, I'd tune around 50hz. Wont' sound good at all for daily though.

That makes sense, I'll try tuning a lot higher and retest. I can swap the port in and out for daily.

And thank you for your post the other day about -6 db test tones, etc.