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Does anyone have any numbers on the 7.5 run at. .35ohms

First off let me start with this. If you run any DC amp below 1 ohm, you WILL void your warranty.

Now lets get to the lesson.

Moral of the story is, if you dont have a reactive ohm load of 1 ohm, the amp will protect and it will put out 0 watts.

So you still want to know how much power the 7.5k will put out, 7500w at 1 ohm reactive and 12v.

If you see .35 ohm reactive at the amp, then you probably just cost yourself $1000 repair bill because your amp is gonna go boom.

i'm kinda laughing at the tool bags worthless ramblings myself. Trying to tell us that an amp wired below one ohm will automatically protect is pretty stupid since we have all seen it done many many times and the majority of us have probably done it ourselves and still have the equipment running to this day.

And .35? We have seen that ran in daily set ups with out the magic smoke coming out. Not all amps are built like the sony amps that i am sure this dude is so used to using that is trying to give us the "Lesson."

I'll second this.. My Sundown SAZ-4500s run at .35 each, and did it daily for about 2 years (until I gutted my hoe to start the rebuild that I havent started yet), and my amps did it on only 2 XS Power D3100s and 3 alternators (1 of which was the stock 105amp alternator) and voltage dropping to high 10volts - low 11volts full tilt on music.

Now if you claim "DC Amps cant work under 1ohm or they instantly go to protect and make 0watts" as you said than I guess the only thing left to say is Sundown Audio >>> DC Audio, even tho they are made in the same factory Sundown parts must be way better!!! :P

Trollolololing aside, I'm sure you just said it so that you prevent the potential customer that does not understand or know the risks and the steps to take when running so low so he would not go ahead and try doing it. However that's an awfully sad way to help teach a person that may not know as much as another person, and hell could even prevent him from choosing the brand you represent due to it. But damn Still cant believe that's what you said, I'm just in shock!

 

 

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i'm kinda laughing at the tool bags worthless ramblings myself. Trying to tell us that an amp wired below one ohm will automatically protect is pretty stupid since we have all seen it done many many times and the majority of us have probably done it ourselves and still have the equipment running to this day.

And .35? We have seen that ran in daily set ups with out the magic smoke coming out. Not all amps are built like the sony amps that i am sure this dude is so used to using that is trying to give us the "Lesson."

Go back and re read the last sentence of my post. I say nothing about wiring at .35 nominal. I run my own amps under 1 ohm and know they down protect or blow.

If you see .35 ohm reactive at the amp

I know that the 7.5k wont stay on this low. Mine would protect at .93 ohms.

Oh and the "lesson" was not about what causes magic smoke, it was about nominal and reactive ohm loads. I hate being asked "well how much power will it put out at .5 ohm" The answer to that is 0. Just because you are wired to .5 ohm doesnt mean a whole lot until signal is applied. Some boxes may be too efficient and not have much rise around tuning at all and the amp will protect from too low of an ohm load.

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i'm kinda laughing at the tool bags worthless ramblings myself. Trying to tell us that an amp wired below one ohm will automatically protect is pretty stupid since we have all seen it done many many times and the majority of us have probably done it ourselves and still have the equipment running to this day.

And .35? We have seen that ran in daily set ups with out the magic smoke coming out. Not all amps are built like the sony amps that i am sure this dude is so used to using that is trying to give us the "Lesson."

Go back and re read the last sentence of my post. I say nothing about wiring at .35 nominal. I run my own amps under 1 ohm and know they down protect or blow.

If you see .35 ohm reactive at the amp

I know that the 7.5k wont stay on this low. Mine would protect at .93 ohms.

Oh and the "lesson" was not about what causes magic smoke, it was about nominal and reactive ohm loads. I hate being asked "well how much power will it put out at .5 ohm" The answer to that is 0. Just because you are wired to .5 ohm doesnt mean a whole lot until signal is applied. Some boxes may be too efficient and not have much rise around tuning at all and the amp will protect from too low of an ohm load.

As he tries to dig himself out from under the carpet....

Just about everyone that talks about wiring their amps under stated stable ohm load is talking about wiring the amps at a nominal impedance, not a reactive impedance.

Farther more, you cant really go and say I want to run my amp and .35 ohms reactive, or .5 ohms reactive, or any reactive impedance, since there is no way to calculate impedance rise prior to the install. The only way you will find that out is after testing your gear... Sure there are ways to get a general idea, but that idea will not be anywhere near correct, and just an idea on how the box will do, let alone the vehicles characteristics will change that impedance rise drastically....

Another thing is you should never count on or factor in impedance rise to assume it is safe to play music at such a low nominal impedance, let alone reactive.

Just to add to the rest, to have a reactive load of .35ohms you would have to wire that amplifier so damn low its not even funny, most people would never even think of doing that let alone trying it. You would pratically have to dead short the amp in order to do it.

We wired my pair of 4500s strapped at .35 already in my buddies CRX which is 0.175ohms per amp, and they turned on and worked, and did a 157.6+db with the car off, termlab on the dash, and a certified score. This was done with the vehicle off and 1 NSB 90 battery. The amps did kick protect 1 click higher than posting said score, but I think any amp would at said impedance and voltage dropping to a nice low 8volts. However with countless burps during testing and db drag regionals the amps took it fine and still continue to work without any magic smoke coming out.

The point of this last part was with the amps almost at a dead short (0.175ohms each), they where still rising to .67ohms each or reactive as you say, just proving the point that if a person meant that they want to wire their amps at .35reactive, you would have to wire the amps at a negative impedance damn near to get such a low impedance rise.

AKA You got caught up slipping, and are now trying to play it off like we misread what you typed...

 

 

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Once again my post had very little to do with what you are wired to at the amp, but more to do with a reactive ohm load. It seems like I am asked everyday "how much power will an amp put out at .5 ohm".

The amp isnt rated at .5 ohm from the factory for a reason.

What most people dont realize is that when amps are tested at the factory, they are tested with a constant ohm load. What I mean by this is the amps are tested at each ohm load that they are rated at and that is the ohm load that the amps are seeing throughout the entire test.(reactive ohm load)

I am no expert on amps and wont claim to be, but I do understand that as a signal is applied to a speaker, the actual ohm load changes between frequencies and is not the same as what you originally wired to(nominal ohm load)

Now back to how the amps are rated.

4 ohm 14.4V 2,200W x 1 2 ohm 4,400W x 1 1 ohm 7,500W x 1 1 ohm 16V 8,600W x 1 1 ohm 18V 9,200W x 1

Those ratings are done with a constant, unchanging, ohm load.(reactive ohm load)

Here is the very first clamp test that I did on my 7.5k.

This test was done in my 2006 Ford F150. I am running 1 Mike Singer 350a alt charging my 5 XS D1400 14v batteries at 16.4v

Voltage started at 16.4v.

Starting impedance is .67ohms

HZ----AMPS----VOLTS----WATTS----OHMS----Voltage Drop

30----mega_shok.gif.9----96.5----7806.85---1.19----15.2v

35----78.2----100.2---7835.64---1.28----15.2v

40----72.2----103.6---7479.92---1.43----14.1v

45----62.2----107.8---6705.16---1.73----14.7v

50----61.5----106.9---6574.35---1.74----14.7v

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i'm kinda laughing at the tool bags worthless ramblings myself. Trying to tell us that an amp wired below one ohm will automatically protect is pretty stupid since we have all seen it done many many times and the majority of us have probably done it ourselves and still have the equipment running to this day.

And .35? We have seen that ran in daily set ups with out the magic smoke coming out. Not all amps are built like the sony amps that i am sure this dude is so used to using that is trying to give us the "Lesson."

Go back and re read the last sentence of my post. I say nothing about wiring at .35 nominal. I run my own amps under 1 ohm and know they down protect or blow.

If you see .35 ohm reactive at the amp

I know that the 7.5k wont stay on this low. Mine would protect at .93 ohms.

Oh and the "lesson" was not about what causes magic smoke, it was about nominal and reactive ohm loads. I hate being asked "well how much power will it put out at .5 ohm" The answer to that is 0. Just because you are wired to .5 ohm doesnt mean a whole lot until signal is applied. Some boxes may be too efficient and not have much rise around tuning at all and the amp will protect from too low of an ohm load.

As he tries to dig himself out from under the carpet....

Just about everyone that talks about wiring their amps under stated stable ohm load is talking about wiring the amps at a nominal impedance, not a reactive impedance.

Farther more, you cant really go and say I want to run my amp and .35 ohms reactive, or .5 ohms reactive, or any reactive impedance, since there is no way to calculate impedance rise prior to the install. The only way you will find that out is after testing your gear... Sure there are ways to get a general idea, but that idea will not be anywhere near correct, and just an idea on how the box will do, let alone the vehicles characteristics will change that impedance rise drastically....

Another thing is you should never count on or factor in impedance rise to assume it is safe to play music at such a low nominal impedance, let alone reactive.

Just to add to the rest, to have a reactive load of .35ohms you would have to wire that amplifier so damn low its not even funny, most people would never even think of doing that let alone trying it. You would pratically have to dead short the amp in order to do it.

We wired my pair of 4500s strapped at .35 already in my buddies CRX which is 0.175ohms per amp, and they turned on and worked, and did a 157.6+db with the car off, termlab on the dash, and a certified score. This was done with the vehicle off and 1 NSB 90 battery. The amps did kick protect 1 click higher than posting said score, but I think any amp would at said impedance and voltage dropping to a nice low 8volts. However with countless burps during testing and db drag regionals the amps took it fine and still continue to work without any magic smoke coming out.

The point of this last part was with the amps almost at a dead short (0.175ohms each), they where still rising to .67ohms each or reactive as you say, just proving the point that if a person meant that they want to wire their amps at .35reactive, you would have to wire the amps at a negative impedance damn near to get such a low impedance rise.

AKA You got caught up slipping, and are now trying to play it off like we misread what you typed...

I am fully aware that there is no way to calculate impedance rise and never said this. This is most of the reason that I wont recommend running under 1 ohm to anyone that is having to come here and ask the question about running under 1 ohm.

That is why the very first thing that is said was "you will void your warranty by running under 1 ohm"

My posts have nothing to do with you or anyone else who has the experience and knows what it takes to run an amplifier so low. It is the guys that dont have any experience running an amp that low daily. In a daily application all you want anyways is to be able to play your system as long and as loud as you want to, you arent looking for every last watt that you can squeeze out of your amp for a burp while chasing a score. It that case, yeah I can see wiring low to try and fight rise. But you know what, if you are doing that, chances are you already know about what your reactive is and how low you can safely go. If you already know these things, then everything we are sitting here arguing about in completely irrlevent.

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The poster asking the question Im sure has no idea on impedance rise. Most people dont, they think if they wire their amp at 1 ohm, its playing 1 ohm, when its not actually playing at 1 ohm but much higher.

So 9 times out of 10, if a person ask what kind of power will they see if they wire the amp at .5 ohms or .35 ohms, they are talking a nominal impedance, not even knowing what impedance rise or a reactive load is....

Either way, just because 1 person pulls XXXX watts form an amp, it doesnt mean another person wired at the same nominal impedance will get the same XXXX watts, due to that impedance rise being different..

This guy just wants to know the potential power he could get from his amp if its wired at a .35ohm nominal load. Not a .35 reactive load like you continue to think...

I know all about impedance rise, some others due to, but like I said the majority of people have no idea, nor can they understand basic ohms law, and some cant even figure out how to wire up a dual voice coil woofer correctly.

 

 

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The way I said it in my first post probably wasnt the best way to get my point across, I will admit that. But my point is still relevant. My only response to those types of questions usually is "the amps will put out rated power at 1 ohm reactive and 12.6v"

99 times out of 100, this goes in one ear and out the other and I get the same response back, "but how much will it put out at .5 ohm"

I am no amplifier or electrical expert and cant explain what is happening that causes the change in ohm loads like say Tony D could, but I try and explain nominal vs reactive the best that I can, in a way that it makes sense to me. Sometimes it doesnt come out the best way possible, but all I am trying to do is give the right information, not trying to argue with anyone.

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Another part that most people dont realize is how much harder it is on your amp and electrical when you run an amp under 1 ohm. Running at such a low impedance creates more current demand to keep the amp happy and running smoothly.

I was in no way trying to come off as an ass, but apparently I did and I apologize for that.

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I didn't read all the comments but to the OP

At .35 nominal you can see normally 3x the rise for actual impedance to the amp, so you would be close to 1 ohm, now since you are wired so low, your damping factor is greatly reduced meaning your efficiency just went to shit lol. So after you consider efficiency which would be in the 70% range would be my guess. You should see close to rated, I would guess 7.5kW at 12 volts at .35 nominial ohm load. Just my 2 cents and this electrical engineer doesn't have any idea wtf he is talking about :)

LBOX88 you know better then to drop the magic smoke lol

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Andrew, arent you at finals? Shut up and get in the lanes lol

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