Re: Crest repair center needed
It Looks like a design decision, to not provide the extra power supply current output and heat sink dissipation required to support 2 ohm operation longer than 20 mSec.
With unlimited current and heat sinks, the 5000i's 2500W 4 ohm power would increase to roughly 5000W, but per the data sheet it only increases to 3000W, so that is current limited. Further it is dissipation limited to only do that for 20 mSec. The 9000i comes closer to a double (2800 increases to 4700), so puts out more current than the smaller amp, but still for only 20mSec.
In bridge mode, you are getting the power output of both channels combined together into one load. While the 5000i spec looks straightforward with 2500+2500=5000, the 9000i and 12000i 8 ohms bridged data looks a little funny. The 9000i 8 ohm bridged power is probably time limited similar to their 20 mSec peak power spec, and the 12000i's 9000W number also suggests a short term burst power spec.
Note: Burst power can be useful for reproducing full range material, only with a band passed sub amp, being driven hard might you bump into the 20mSec limitation, but to do that you would have to be working it very very hard (less than 3 dB crest factor), so I suspect they work OK for "most" sub applications too.
JR
