This amp is stated to deliver it's 500w output between 1.5 and 4 ohms, any idea what would happen at 8 ohms? Would it ramp the current draw out of sight?
It would draw less current as stated. The 500/1 works via voltage rails and has different rails depending on the load presented and voltage present to the amplifier. At 8 ohms, the amplifier would remain on the same voltage rail (highest) as it would for 4 ohms, power output would be similar to other amplifiers in that regard, you can expect a little more than 250W due to the efficiency/headroom of an amp with a higher impedance. I'd say closer to 300ish with that load, especially since the amp is underrated.
Besides tube amps all of today's car amplifiers can be viewed as simple voltage sources which are limited in output by the maximum amount of voltage they can produce. Given an adequate power supply this max voltage is determined by the amplifier's "voltage rail".
If I understand the way those slash series amps work they have three voltage rails, the highest being utilized at 4 ohms. When you hook up lower impedance loads the amp automatically switches to a lower voltage rail to limit power. However, with any higher impedance your stuck utilizing the "4 ohm rail" and the maximum amount of voltage the output circuitry using this rail can produce, call it V4ohm.
When utilizing this voltage rail the maximum amount of power that can be produced is given by
Pmax=V4ohm^2/R
so doubling the impedance essentially halves your potential power output just like it would on any "single rail" amplifier.
At least I figured out how to use subscripts. Still like Jonathan's answer better.
-Fishy
Anonymous
Posted on
I have a question, firstly let me start off my saying, i recently bought 2 brand new 1600 w/max amplifiers and 4 12" 600w/max new subwoofers. the Brand is CUSPID, i never heared of it before, but for the price i thought i would give it a try. Are these CUSPID things any good? please leave me some first or second hand accounts you had with this equipment. PS- the amplifier is a 4-channel but is 2x80wt RMS, does that make any sense?
