Just a question about impedance rise.... Does nominal impedance matter?

[bigblackdodge]

Here is the question coming from a noob, brace yourself.

Does nominal impedance matter as to how much rise or drop there is?

Example- useing numbers from n3w_3ra's post

Quote from initial clamp

Wired to 1 ohm nominal :

 

1170 Watts @ 12.5 volts

1.97 ohms after impedance rise

 

Wired to 0.5 ohm nominal :

 

1490 Watts @ 11.1 volts

0.85 ohms after impedance rise

Ok, so considering there was a rise of .97 when nominal impedance was at 1ohm and rise of .35 from .5ohm. So would it be ignorant to assume possibly with a higher nominal impedance a rise or fall of impedance would be more drastic? Say If I were to wire 4 subs to a 2ohm load think it would rise more than it would with a .5ohm load?

And please note this is all just theoretically speaking/asking/whatever. Im using this knowledge toward buying a matching amp for my current build. Have 4 dual 4ohm subs on the way and am debating on final impedance to pair with an amp or 2. Either Choice A: Get a large powerful amp (2500+@ 2ohm) and run on 2ohms. Choice B: Get a well made smaller amp (2500+) and run at .5ohm. Or Choice C: a couple of amps and run each pair of subs at 4ohms.

Also note if it appears im taking this too far out of proportion ill just do what i been thinking, just say fug it buy a lanzar opti4001d and run at .5 ohm for 4000 watts.

Click to read more...

 

[globalminds_ent 10+ year member]

Help a supporting vendor with the purchase of your opti4001 ill even throw in a zero gauge Amp kit for $35

 

[bigblackdodge]

Thankyou and i will keep that in mind!

 

[Beatin' 10+ year member]

box rise rarely matters for daily music pounding.

It is most relevant when playing a test tone in large boxes, like an spl competition perhaps?

 

[bigblackdodge]

ok i figured i was thinking too much on it. I was just trying not to cheat my obsidian subs. there rated at 600watts conservatively each and i was considering the opti4001 at .5ohm would produce 4000 watts. so that means 1000watts to each subwoofer but counting for possible rise I will probably never get the full 4000 or 1000 per sub. and thats ok for me.

 

[n8skow 10+ year member]

The impedance your amp sees will not be a flat value. It's going to be different at different frequencies (typically the highest near turning) and lower with frequencies away from tuning. In other words - near tuning is where your woofer impedance will rise the most (and thus the lowest power), but at a frequency - say 10hz above or below tuning, impedance is going to be a lower value - and thus the woofers will see more power...

So yes, it's totally conceivable your woofers will see the full output of the amp - but there's going to be time that they are only see a fraction of the power as well.

 

[bigblackdodge]

The impedance your amp sees will not be a flat value. It's going to be different at different frequencies (typically the highest near turning) and lower with frequencies away from tuning. In other words - near tuning is where your woofer impedance will rise the most (and thus the lowest power), but at a frequency - say 10hz above or below tuning, impedance is going to be a lower value - and thus the woofers will see more power...
So yes, it's totally conceivable your woofers will see the full output of the amp - but there's going to be time that they are only see a fraction of the power as well.

THAT is exactly what I was wondering. Awesome answer man. I do appreciate it! Now I feel safe feeding 1000 watts each when rated 600. The subs will recieve the whole 1kw but only at certain frequencies. It wont be recieveing 1kw continuously unless its playing continuous tones around tuning and less at tuning fq. This makes alot more sense. I figured there was some kind of simply way to put it.