Long term power limit of 2.5" Aluformer dual 4 layer VC

[kipman725]

I want to define some long term power limiters for my subs using Pyle plpw15D drivers as I'm going to hook them up to a bigger amp.   However as they are car audio drivers with non PA coils I'm not sure what a sensible long term power limit would be:

the former is alu which should increase power dissipation capabilities, 2.5" dia, 4 layer with two voice coils.  They have a vented pole peice.  The manufacturer rates the driver at 1000Wrms which from rules of thumb I have seen would suggest around 500W as a sensible long term limit.  I also found this chart from powersoft:

from which I would guess the closest is 3" mid-bass giving a long term limit of 150W? (Per driver, my subs use two drivers in series)

[peniku8]

Bennett from B&C suggested setting the true long term power limits around 1/10th of the program power, which would be 500W for an ipal for example, or 360W for the 4,5" 21DS115. I have no clue how good the cooling is on the Pyles, but power handling also depends on cabinet type, as you get less excursion (so less cooling) in sealed cabs for example, but I'm pretty sure you're not using sealed cabs for PA. You could try running the sub at a certain power limit for a while and measure the TS parameter shift. Or measure it acoustically and see where power compression sets in, maybe that is a good indicator as well.

[kipman725]

Boxes are isobaric bass reflex with all 4 voice coils over two drivers in series making a 16 ohm nominal box.  I observe up to 2dB power compression on a 94V sweep but its at the frequencies where excursion is maximized, I don't think I can see any heating effect in the data I have.  I don't have data for higher voltage sweeps because that's as much as I could get out of the amp I had at that time.  I used to run these drivers in sealed cabs and this resulted in the motor structure glue failing jamming the voice coil, the voice coils suffered mechanical damage (scrapes) but didn't burn.  This makes me think that the power handling is way better than a 2.5" voice coil made using conventional pro audio voice coil formers like kapton.  Due to the design of my boxes I can touch the magnet of the driver during use of the outer isobaric driver and found that it was barley above ambient when driving all night from a P7000s channel (77Vrms).   All suggests I should do more comprehensive testing but I live in a terraced house so this is difficult.