Have you measured impedance rise in your daily?

[JakeW]

2 1500/3000w dc 12s. Taramps md5k 2 ohm, wired to 2 ohm. Played a test tone, clamped 3013w at 5.6ohms. Is this information useless since I play music and not burp continuously? Would like to add some rms to the system, looking for opinions on the proper way to. Swap 5k out for 8k to compensate? 8000at 2ohm, 5120 at 4ohm, approximately 4800 at 5.6 ohm if it provides the same power curve as this md5

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[THATpurpleKUSH 5,000+ posts]

Impedance rise is usually 3-4x nominal and gets higher as you near free air resonance. It varies with frequency so 30hz will be a different impedance than 50hz.

You have 2 1500w subs and you are clamping rated power, why add more?

 

[JakeW]

Impedance rise is usually 3-4x nominal and gets higher as you near free air resonance. It varies with frequency so 30hz will be a different impedance than 50hz.

You have 2 1500w subs and you are clamping rated power, why add more?

Not to be retarded, but would like to have 2-2200 to each sub... in the pursuit to be louder

 

[nauc 10+ year member]

build a bigger box

 

[THATpurpleKUSH 5,000+ posts]

Not to be retarded, but would like to have 2-2200 to each sub... in the pursuit to be louder

Then you need to double cone area or power if you want gains you can actually hear.

 

[hispls 5,000+ posts]

Is this information useless

Yes, because impedance is different at every frequency. Go ahead and try a bigger amp if you like but it may not translate into a whole lot more output especially if you haven't got electrical system to support it. Perfect world, going up to the 8K amp may give you about 1 more click on the volume knob worth of output.

Impedance rise is usually 3-4x nominal and gets higher as you near free air resonance.

No it isn't and no it doesn't. For reference, z-max at Fs (47hz) is 6.25ohm free air, Z at 47hz in the box is 3.5 ohm and Z-max in the box is 6 ohm and at 30hz. Free air impedance at 30hz is 2.05 ohm.
It would be very poor practice to count on such generalizations if you were attempting to put yourself in a position where any of this is important. IF you really needed to know your impedance curve you must measure it in box in vehicle. This can be done with some graph paper or spreadsheet, tone generator, and DMM or O-scope or a tool such as Dayton DATS.

 

[THATpurpleKUSH 5,000+ posts]

Yes, because impedance is different at every frequency. Go ahead and try a bigger amp if you like but it may not translate into a whole lot more output especially if you haven't got electrical system to support it. Perfect world, going up to the 8K amp may give you about 1 more click on the volume knob worth of output.

No it isn't and no it doesn't. For reference, z-max at Fs (47hz) is 6.25ohm free air, Z at 47hz in the box is 3.5 ohm and Z-max in the box is 6 ohm and at 30hz. Free air impedance at 30hz is 2.05 ohm.
It would be very poor practice to count on such generalizations if you were attempting to put yourself in a position where any of this is important. IF you really needed to know your impedance curve you must measure it in box in vehicle. This can be done with some graph paper or spreadsheet, tone generator, and DMM or O-scope or a tool such as Dayton DATS.
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For the sake of simplicity i didnt bother to say there are 2 impedance peaks and those change when an enclosure is factored. But impedance will always be highest at z max.

 

[JakeW]

80ah agm up front, 1/0 big 3, 326a alt, dual runs 1/0 to a titan8, dual runs & grounds on amp. Not sure if that’s sufficient for an 8k or not

Yes, because impedance is different at every frequency. Go ahead and try a bigger amp if you like but it may not translate into a whole lot more output especially if you haven't got electrical system to support it. Perfect world, going up to the 8K amp may give you about 1 more click on the volume knob worth of output.

 

[hispls 5,000+ posts]

Not sure if that’s sufficient for an 8k or not

One way to find out I suppose.

For the sake of simplicity i didnt bother to say there are 2 impedance peaks and those change when an enclosure is factored. But impedance will always be highest at z max.

Free air there are not two peaks, there is one at Fs, then impedance will approach infinity as frequency raises due to the inductance of the coil. Z-max does mean the highest impedance, but that will not be the same frequency as Fs nor system resonance once it's in a box.