1500d question with electrical system

[trunks9_us 0]

oh no, impossible.

Whatever the DCR value is, the REvc spec, the active impedance will NEVER EVER EVER be at or below that value.

This is why people can run 1 ohm stable amps at 0.25 ohms.... because the resistance is so high. Now, they can't d that for music for certain frequencies may have very high rise which allows running very low loads possible because the amp is still seeing a load much higher then one expects.

If you ever want to see this in person, get a DMM and an ammeter and burp a frequency for several seconds.

Record the voltage and amperage output at the same time. Do not take peak values, take consistent output values and at the same time. Divide the amps INTO the volts to get active resistance.

I think i am starting to understand you now cause i have the multimeter up on the 2 subs right now when its wired parallel and its jumping from 2.1 - 2.5 slowly going up and down changing its just sitting here in my living room. it was at 2.5 now its at 2.1 stuck thee for now been sitting the multimeter on it for 5 min now. it keeps changing going down now its at 2.0 was at 1.6-1.7 a sec ago and its just sitting there doing nothing.

Edited July 26, 2008 by trunks9_us

[jonbearsmt 919]

shizzon is right.. the ohm load will rise while playing... its what people call box rise. so your 2 ohm load maybe as high as 20 ohms at times.

look the kicker amp was prolly a better buy for your application..... all i was saying is that a sundown is never a waste of money...

even if your not happy... just pick up another 1500d strap that shit at 2 ohms for 3000 watts.

edit: the wind in the air will make your ohm reading change.

[shizzzon 461]

i do not know if i am following you or not but to measure the resistance, the sub(s) must have a signal going to them, the voltmeter must be either on the speaker terminals on amp or subs terminals and an ammeter must be strapped around only 1 of 2 wires, pick one, positive or negative.

You gotta get both values on both meters at the same time and while the numbers are steady instead of moving all the time. The only easy way to do that is by playing a test tone.

[trunks9_us 0]

shizzon is right.. the ohm load will rise while playing... its what people call box rise. so your 2 ohm load maybe as high as 20 ohms at times.

look the kicker amp was probably a better buy for your application..... all i was saying is that a sundown is never a waste of money...

even if your not happy... just pick up another 1500d strap that chit at 2 ohms for 3000 watts.

edit: the wind in the air will make your ohm reading change.

thats exactly what i will do in the future but for now it will be a good buy to see what the amp is like and wont damage my electrical system. I am glad i have learned this lesson from shizzon because now everytime before i buy my amps and subs i will make sure there right for each other. This was a good lesson learned thx shizzon. I wish i knew this a long time ago though but mistakes wont be made again with this. Sry for being so hard headed shizzon should of checked on what you said before i ordered the amp. although i did pay for it is has not been on order yet i could cancel the order but i dont want to piss the guy off so what should i do call him tomorrow and cancel or just try it out and see what its all about cause thats whats im down for.

[trunks9_us 0]

i do not know if i am following you or not but to measure the resistance, the sub(s) must have a signal going to them, the voltmeter must be either on the speaker terminals on amp or subs terminals and an ammeter must be strapped around only 1 of 2 wires, pick one, positive or negative.

You gotta get both values on both meters at the same time and while the numbers are steady instead of moving all the time. The only easy way to do that is by playing a test tone.

the way i did it was i just wired them up in parallel sitting here then put the multimeter to the voice coil on one of the subs one on the red and on on the black. Will doing it that way not work?

[shizzzon 461]

no that wont work.

When people say that your resistance will fluctuate all the time, that means it will fluctuate with what frequency is being played AND because it's playing, it's receiving a signal.

When nothing is being sent through the sub, it's Revc value is seen by a multimeter.

To see it's live load, it must be playing something. At this time, you would need a multimeter and ammeter and that method was posted above on how to find that.

[trunks9_us 0]

ah Ha! That's what i needed.

So, wired in parallel, both of them would get you a 1.6 ohm load.

That's perfectly fine to run off of a 2 ohm stable amp.

I would be looking for a 1500w amp rated @2ohm. You'd get more bang for your buck.

Here is a list of some amps that you can do your own research on that will benefit you -

Alpine MRP-M2000

Kicker ZX1500.1

These amps may require you to do what bigjon said because these amps fit your application better so you'd get more power out of them than the sundown.

Hey shizzzon I am now starting to understand the ohm loads you were trying to explain to me now with giving it alot of power but clipping it or unclipped and not as loud i now understand this so my question to you is If i bought another 1500d then strapped them to both run them both at a 1 ohm load which would give me a final 2 ohm load for the amps which would then match up for the subs ohm load and the subs should still be able to handle the power as well given the fact the subs are rated at 1200 rms like you said in a previous post. The only problem i am having trouble with is how do i strap them to a 1 ohm load on the amp to run 2 ohm load for the subs? Is this even possible?

The only other thing I can think of is if these are dual 4 ohm subs and the manual doesnt give me a wire config for a 4 ohm load with 2 subs cause they say there dual 6 ohms. So i was looking on the12volt sub config and i saw this would this work if i did this for the 2 subs?

http://www.the12volt.com/caraudio/woofer_c...sp?Q=2&I=42

Or should i call jbl and ask them what to do?

Edited September 1, 2008 by trunks9_us

[trunks9_us 0]

ah Ha! That's what i needed.

So, wired in parallel, both of them would get you a 1.6 ohm load.

That's perfectly fine to run off of a 2 ohm stable amp.

I would be looking for a 1500w amp rated @2ohm. You'd get more bang for your buck.

Here is a list of some amps that you can do your own research on that will benefit you -

Alpine MRP-M2000

Kicker ZX1500.1

These amps may require you to do what bigjon said because these amps fit your application better so you'd get more power out of them than the sundown.

Hey shizzzon I am now starting to understand the ohm loads you were trying to explain to me now with giving it alot of power but clipping it or unclipped and not as loud i now understand this so my question to you is If i bought another 1500d then strapped them to both run them both at a 1 ohm load which would give me a final 2 ohm load for the amps which would then match up for the subs ohm load and the subs should still be able to handle the power as well given the fact the subs are rated at 1200 rms like you said in a previous post. The only problem i am having trouble with is how do i strap them to a 1 ohm load on the amp to run 2 ohm load for the subs? Is this even possible?

The only other thing I can think of is if these are dual 4 ohm subs and the manual doesnt give me a wire config for a 4 ohm load with 2 subs cause they say there dual 6 ohms. So i was looking on the12volt sub config and i saw this would this work if i did this for the 2 subs?

http://www.the12volt.com/caraudio/woofer_c...sp?Q=2&I=42

wire or the subs in dual 4 ohm is the same as dual 6 ohm for the 1.5 / 1 ohm load so it all comes down to the amp then i guess.

Or should i call jbl and ask them what to do?

[jonbearsmt 919]

read this.

http://mobile.jlaudio.com/support_pages.php?page_id=161

[trunks9_us 0]

I will bet $100 that those subs never see an even 2.0 ohms or lower at any frequency.

That's just the way it is.

I'm not new to impedance curves.

And as stated before, I've seen dual 4 ohm coils rated LOWER than JBLs coils wired in parallel.

Why? Because other companies are showing nominal resistance. A resistance guaranteed not to fall below this value.

JBL has rated their coils practically at the rest value, i guess for more advanced users.

You have compared apples to oranges i'm afraid.

They clearly state the 12 uses 6.4 or 6.5 ohm coils. They could have rated these subs as dual 8 ohm. Everyone else would have i'm sure.

Just to let you know in the future-

a wired load of-

0.6, 0.7, 0.8, 0.9 works with a 1 ohm stable amp.

1.2, 1.4, 1.5, 1.6, 1.8, 1.9, 2.0 works with a 2 ohm stable amp.

2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 3.9 works with a 4 ohm stable amp.

I left out some loads because i havent never seen those loads before but am sure they would work also since they fall in between the low and high range readings.

Hey i got another question for ya as well What would the load be if i was using 3 of these subs (series/parallel) = 4 ohm load

Voice coils wired in series, speakers wired in parallel. thats what the sub wiring diagram would call for but since you know a bit more about finding out the ohm loads let me know.