Gain, Output, and Thermal Damage

[idiot 10+ year member]

I have a gain-setting question. It’ll probably show my inexperience, but better safe than sorry…

I’m running a sealed RL-p15 (~2.2 ft^3), powered by an Avionixx 1200.2. Using the sqrt(P*R) formula and a multimeter, I tried to set the gain to output only ~800W (sqrt(4*800) = 56.6V). The problem is that this is not loud enough at normal listening levels. The cone moves very little, even on sine waves below 35Hz.

When I set the gains for both my component amp and the Avionixx, my head unit (RF 8250) was set to volume level 26, and a level of 16-18 is normally as loud as I take most music. At this level, I don’t feel that the sub has enough presence, and it barely moves but on the lowest of notes. To test higher output, I brought my head unit up to 26 (which would theoretically correspond to ~800W from the amp, right?). This is the kind of output I was seeking for daily use. But even at this level, the sub doesn’t come close to reaching its mechanical limits, even on low notes, and I know that it can play much louder.

But I’m not really sure what to do, since I don’t want to be in danger of thermal damage. My amp is capable of putting out 1200W, but I don’t think it should be necessary to dump that much power in order to attain maximum excursion from my current setup. Any thoughts?

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[theCybe 5,000+ posts]

Check your other amp settings, .. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[idiot 10+ year member]

Bass boost is disabled, and I've set the crossover properly (switching it to full-pass solves nothing). Those are the only settings it has.

 

[idiot 10+ year member]

Every other tutorial I’ve read wants me to set the head unit around the 2/3 mark, to estimate the nonclipped HU range. This method is incorrect?

As for the Punch Bass setting… I’m using the Denford unit, which doesn’t have this.

 

[idiot 10+ year member]

Well, I readjusted the gains per your recommendation, and everything seems better. I’ll have to give it a longer drive tonight to really see, though. I also bumped the power up a bit, since Mike is now recommending 800-1200W on his forums, for various size enclosures. So I don’t think that a thermal problem should arise from the 900-1000W I’m sending it.

Before I messed with anything, I tested the voltage at volume level 20 (when I had previously set the max at 26), and I was only seeing 13.6V. So that may very well have been my problem. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif