Max output from amp !

[audiobaun 5,000+ posts]

 

[Water Bear]

So what method will you use to plot the impedance of your woofer in the box in your vehicle? How will you account for impedance changes due to compression if you need to determine power at maximum output?

There is some confusion here. I'm not arguing that you should try to figure out your woofer's impedance as a function of frequency by plopping numbers in software or something along those lines and then getting power from that. We all agree, I imagine, that using something a la the AMM-1 is the way you'd actually do it in practice.

My point is more that this information isn't really helping OP. Maybe he wants to spring for a $350 measuring instrument, but I assume not. He's chosen to go the multimeter route. 2 ohm is the nominal impedance of his sub, meaning that they (the manufacturers) expect it to present that load at some practical frequency in actual application. He should be seeing the right numbers coming out of his amp, and the easiest explanation is that his input signal is too low.

Somehow this thread is devolving into nit-picking minutia that doesn't really help OP. He said that it distorts at 38 - we already know that. We aren't talking theoreticals here. I don't know how he got that number and I don't care - I'm willing to run with it.

 

[TheRadio]

What is so hard about using a clamp meter and dmm to measure current and voltage and using elementary math to figure wattage and impedance rise from there?

The neuroticism in this thread is absolutely astounding!

 

[hispls 5,000+ posts]

2 ohm is the nominal impedance of his sub, meaning that they (the manufacturers) expect it to present that load at some practical frequency in actual application.

OK, so what frequency? How do we determine the frequency when OP gets this all installed and if he is not measuring at the one specific frequency where his amp might actually see 2 ohm how is he going to estimate power?

The correct answer is he needs to set his gain by ear while listening to music if he intends this to play music, if he is chasing numbers he needs to set the gain with an SPL meter to find maximum output. This got over-complicated when OP decided he needed to figure out precisely how much power he is getting without understanding impedance of a loudspeaker system and without the willingness to buy the proper tools to measure real-time power.

 

[audiobaun 5,000+ posts]

OK, so what frequency? How do we determine the frequency when OP gets this all installed and if he is not measuring at the one specific frequency where his amp might actually see 2 ohm how is he going to estimate power?

The correct answer is he needs to set his gain by ear while listening to music if he intends this to play music, if he is chasing numbers he needs to set the gain with an SPL meter to find maximum output. This got over-complicated when OP decided he needed to figure out precisely how much power he is getting without understanding impedance of a loudspeaker system and without the willingness to buy the proper tools to measure real-time power.

Ive been tuning by ear for over 25 years.. and so far havent let me down yet thankfully