I've been to the US festival with an impressive 500 kW audio power capacity, enough to rock the San Bernadino valley with 1 watt per person attending. But it was perfect stereo even with delayed sync audio to the satellite scaffold towers with the firehose turrets to cool the audience, so 1500W is pretty puny. Even before this I had heard and found a French Canadian disco in the '70s with Quad sound each with dual 15" woofers and each driven by a parallel rack of Crown DC300's.
I found this event in a modified RC church by the seismic waves many blocks away at night, so none of this impresses me.
I am impressed no one has ignited the H2 gas generated by the overvoltage charging of glass matt bateries to 16V and become a Darwinian Award winner helping to reduce the gene pool of mancave-on-wheel dwelling magnetic shakers.
The speaker coils need to be ferrofluidically cooled and the power source ESR needs to 0.1% of speaker impedance for high quality thumps without overshoot. The Capacitance in batteries far greater than caps but may have a higher ESR during chemical equalization from charge to discharge.
The lack of engineered solutions astounds me.
Has anyone considered this?
1) 350A alternators are cheper and readily available with 24V trucks for 24V batteries for improved lower conduction losses in cables at 6kW loads, independant of the 12V system.
Even better use a 48V alternator @ 40A and 48V batteries for 2kW charging and no conversion.
2) the C2 Audio class E amplifier simply boosts the battery voltage to achieve the power in a 4 Ohm system.( or other)
Thus a 4 Ohm load at 2500Wpk sound system could draws 25A at 100V or some other DC voltage.
So it would make more sense to PWM switch the 48-54V battery to 100V with IGBTs with negative feedback and a gain of 100 could use RdsOn of <0.1% of 4 Ω or 4 mΩ running at 100Vdc with 2500 W available to the 4Ω speakers.
This 3 phase bridge is capable of far less ripple current damage to battery and thus no need or caps.
https://ixapps.ixys.com/DataSheet/GMM3x60-015X2.pdf
150V, 50 A, 19 mΩ Which would reduce to 0.19 mΩ with x100 Vgain negative feedback.
Thus NO boost SMPS regulator, no big Caps, just negative feedback to lower driver ESR inside the Audio Amp is required which only adds ESR , the lower currents and voltage match the Amplifiers needs.
This is not a complete design, just a commentary on bad design of seismic car audio technology.
BTW good performance for standby power in a load acid 12 V(14.2 max) battery is 1.5AH per pound weight.