12w6 vs 13w6

[cotsretribution]

does that make sence^^^?

 

[helotaxi 5,000+ posts]

first of all distortion allways exists unless you are in a vacume with all perfect equiptment and no interference of any kind... lower amplication only makes it less audible just as it makes the music less audible... but it's still there....

Distortion is expressed as a precentage compared to the total signal. 1% distortion at 1W is no more or less audible that 1% distortion at 1000W. Remember that not only is the distortin amplified, but the signal itself is amplified as well.

second (this is a important one)... A VOICE COIL'S ABILITY TO CHANGE ITS CURRENT GETS FASTER AS THE POWER INCREASES... i don't understand how someone who is apperantly so knowledgeable about audio doesn't see this

I don't see it because it isn't true. Resistance to a change in current is expressed as inductance. The voicecoil of a sub has an inductance value, because of the dynamic nature of the voicecoil in the gap, this value does change a bit depending on frequency. But it does not change much based on power (other than to go up thanks to increased resistance from a heated coil menaing that it actually increases with an increase in power. This increases distortion, too BTW.)

here's where your point comes in.... as the power increases the sub also gets less linear because in effect every time the sub reaches it's "resting point" it is, in effect, thrown to its excursion point in this part of the phase as the sub goes further and further out from the center the coil loses more and more control makeing it less accurate...

I was with you up until here...

the fact is that the 13w7 has the ability to hit full excursion and still sound somewhat decent and have an on the map SQ reading but as you decrease power transient responce gets better untill you get to 1000watts where sq decreases not having anything to do with to do with excursion or hom the suspension is designed but because the speaker requires a specific amount of power to reach maximum sq now

But that made no sense whatsoever.

now a point that you haven't said but i believe you might understand is that the reason sound quality usually doesn't decrease at lower levels is because... as the coil's ability to contribute its "current magnitude-forced transient responce" decreases, motor gains control raising the transient response.

Again, What?!?

but underpowering is different than turning the volume down...

No actually running less power and turning the volume down are exactly the same thing, with exactly the same results.

jl amps are recommended to put out a specific output voltage and the subs are designed to recieve a certain voltage... this amount of voltage is regulated by the amp to make the change in volume by the source... to not interfere with sound quality and to give a balance of sound(so the volume of the substage increases and decreases at a comparable level to the frontstage) but all of this is set from a reference level predeterimined by the amp input, amp output, sub resistances, sub efficiency, and many other factors, but subs aren't as flexible in application as most people believe.

Again totally off base. The "specific output voltage" will only be reached under the exact conditinos with which the input level control was set. Any other condition will result in more or less voltage.

(((((PAY CLOSE ATTENTION TO THIS PART...))))) a 500/1 will never be able to power a 13w7 and give a flat responce because for you to reach half of the subs input/output potential you must set the amp to full gain... with that said an amplifier works exponentialy multiplying the signal input,so a sub that is useing half of its potential but the full potential of the amp will have far more noticeable distortion because if the distortion is at a higher amplitude than the music input, which it almost allways is, the distortion will be amplified more than the music is....

If the amp is capable of producing its rated power with an inaudible level of distortion (the JL amps are so capable) then there will be no difference in audible output between the 500/1 producing 500watts and the 1000/1 producing the exact same amount of power.

heres an example: lets say you want a 13w7 to run at 250 watts at maxium potential this will give you horrible sound quality with a 250/1 because gain is set on maximum... but possibly good sound quality with a 1000/1 set to a level of 25% which should give you about that 250 watts you were lookin for but there is another problem... 25 percent of your system's volume is reaching your "maximum sub potential of 250 watts... solution? smaller substage.... your front stage should be able to keep up with your subs maximum potential at all times, other wise you are forced to underpower your subs... or use some kind of attenuatore on the input of a lager amp to retain the same quality at a lower level... you simply can't underpower your subs (!!!!!!you HAVE to have a amp powerfull enough for at least IDEAL output inorder to retain sound quality at lower levels!!!!!) i say again you can't underpower your subs and get good sound quality!! some of those people who have big subs in their car have big subs that handle less power or they have BIG powerfull amps the fact is ....

Again, all total BS. If the amp produces the amount of output you want/need with the sub in question, it doesn't matter that the sub could handle 10,000 watts, it will sound just as good with only 250w, it just won't be as loud. If the amp is making audible noises at its rated power, then the amp is either over-rated or broken.

the fact is that 2 amps pushing the same power one at 25% one at 100% will not produce the same quality... so yes! the 13W7 REQUIRES 1000watts to have the best sound quality at all volume levels ... if the 13w7 is too loud for your SQ if you want to run 500 watts get the 10 or a lesser series you just can't underpower a sub and get good quality

With a good amp you should not be able to tell the difference between one running its full rated power and one rated for 4x more power but only running at 25%. That is a fact. If the smaller amp is producing audible distortion at its full power, that is a problem. Fact: I was very pleased with my XXX12 (1600 RMS rating) running off a 400w amp. No distortion from the amp, sub sounded perfect. Going to a bigger amp would have only given me the potential to get louder, it would not have made it sound any better.

 

[cotsretribution]

Distortion is expressed as a precentage compared to the total signal. 1% distortion at 1W is no more or less audible that 1% distortion at 1000W. Remember that not only is the distortin amplified, but the signal itself is amplified as well.I don't see it because it isn't true. Resistance to a change in current is expressed as inductance. The voicecoil of a sub has an inductance value, because of the dynamic nature of the voicecoil in the gap, this value does change a bit depending on frequency. But it does not change much based on power (other than to go up thanks to increased resistance from a heated coil menaing that it actually increases with an increase in power. This increases distortion, too BTW.)

I was with you up until here...But that made no sense whatsoever.

Again, What?!?No actually running less power and turning the volume down are exactly the same thing, with exactly the same results.Again totally off base. The "specific output voltage" will only be reached under the exact conditinos with which the input level control was set. Any other condition will result in more or less voltage.

If the amp is capable of producing its rated power with an inaudible level of distortion (the JL amps are so capable) then there will be no difference in audible output between the 500/1 producing 500watts and the 1000/1 producing the exact same amount of power.

Again, all total BS. If the amp produces the amount of output you want/need with the sub in question, it doesn't matter that the sub could handle 10,000 watts, it will sound just as good with only 250w, it just won't be as loud. If the amp is making audible noises at its rated power, then the amp is either over-rated or broken.

With a good amp you should not be able to tell the difference between one running its full rated power and one rated for 4x more power but only running at 25%. That is a fact. If the smaller amp is producing audible distortion at its full power, that is a problem. Fact: I was very pleased with my XXX12 (1600 RMS rating) running off a 400w amp. No distortion from the amp, sub sounded perfect. Going to a bigger amp would have only given me the potential to get louder, it would not have made it sound any better.

most of that was explaining that i think an amp has better sq if its not working as hard but i'll have to do some studying and tests before i can argue about it anymore but i do dissagree.. i'll get back to you on this

 

[Prowler573 5,000+ posts]

most of that was explaining that i think an amp has better sq if its not working as hard but i'll have to do some studying and tests before i can argue about it anymore but i do dissagree.. i'll get back to you on this

And from what I have seen up to this point you'll most likely (once again) be flatly shot down by inarguable fact opposing misinformed opinion but yet it still will continue to not sway you one little bit.

You're entertaining, I'll say that much.

 

[helotaxi 5,000+ posts]

i understand your consept in the first point but its not a correct annalogy its more like your car will have better mileage and run smoother at 60 than mine will

Geneeralization that may not stand up to real world usage. Its entirely possible that your car was designed to operate forever right at its max level and that his car needs the extra speed to run at its most efficient level. Many times it is so with amps. Class A/B amps for example are at their most efficient when they are running full tilt. The typical torture test of a Class A/B amp is to run it at 1/3 power until it shuts down.

yes but imperfections are amplified more when the amplification factor is greater

The amplification factor is a product of the amp as a whole, not just the input stage. If the signal from the HU is 2V, a 1000W amp actually has a higher gain factor than a 250W amp. The position of the gain control is based on the input signal and the desired output of the amp. If the components ahead of the amp are decent and the system has a low noise floor and the amp has a good input stage, you should be able to set the gain control where ever it needs to be to get the power from the amp, whether that be at min or max. Actually, the gain would be set the same for a 250/1 and a 1000/1 to get full power from both amps from the same signal. The larger amp would actually increase the volume of any noise more. Yes you could go with a much larger amp and keeps the gains low trying to improve your s/n ratio, but good components will keep that from being needed.

purty close in this example (250 is half of the smaller amps capacity) but if i wanted 500 wats i'd go with a 1000/1... my point is that you can get better quality when you are not using all the power that the amp can give

There is a huge difference between "all the power that the amp can give" and rated power. Most all amps can produce more than their rated power at the cost of distortion. This is why power numbers without distortion numbers are worthless. Better amps have better distortion numbers. If the amp is CEA2006 compliant, it should be able to make rated power without exceeding 1% distortion. An under-rated amp will make its power with less distortion than that. Even 1% is below the threshold of audibility.
Face the music, you can't validate any of your statements with anything that resembles fact. Sit back read and maybe, just maybe, some of us might be able to teach you something.

 

[cotsretribution]

Face the music, you can't validate any of your statements with anything that resembles fact. Sit back read and maybe, just maybe, some of us might be able to teach you something.

this would be why i said i'll get back to you... all i KNOW is my freind had 2 type Xes he had 1000watts going to each of them (the max of the amp) we figured the exact power going to them to be about 990... and they were full of distortion, sounded horrible... he got some bigger amps because he was planning on getting some 15's but he hooked them up the exact same way as the old amps and they sounded very good no audible distortion we wanted to know why we figured the power to it to be just under 1000 wats exactly and it still sounded great... the bigger amps were rated at 2000W

 

[helotaxi 5,000+ posts]

Your example there proves nothing. The first amps were being pushed past their real limit. They were producing audible distortion. Just because they do so does not mean that other amps do. Using inferior equipment not really capable of doing what it claims lends no weight to any argument other than one about lack of ability to polish a turd.

 

[cotsretribution]

Your example there proves nothing. The first amps were being pushed past their real limit. They were producing audible distortion. Just because they do so does not mean that other amps do. Using inferior equipment not really capable of doing what it claims lends no weight to any argument other than one about lack of ability to polish a turd.

so your saying not amps will behave the same way my buddie's did?

 

[helotaxi 5,000+ posts]

I'm saying that an amp that is not being driven beyond its real capability will not sound like shit. An amp capable making its rated power while maintaining inaudible levels of distortion will do just that. If an amp can't reach its rated power without audible distortion, either the amp is broken or the ratings are BS.

 

[cotsretribution]

I'm saying that an amp that is not being driven beyond its real capability will not sound like shit. An amp capable making its rated power while maintaining inaudible levels of distortion will do just that. If an amp can't reach its rated power without audible distortion, either the amp is broken or the ratings are BS.

i agree completely! but a 250/1 pushing a 13w7 is being driven beyond its its real capacity thus makeing that amps 250 watts(maby as mush as 300) sound like shit where the same amount of power from the 1000/1 or even a 500/1 would sound good i don't see wat u are agrueing about... is this not correct? unless you mean that the amp can't produce more power than it is rated for?

 

[helotaxi 5,000+ posts]

Getting 250 watts from a 250/1 is in no way pushing it beyond its limits. Not even close. It's MADE to put out 250watts with less than 1% distortion. I'm still at a loss as to why you don't get this. I'm not talking about asking the amp to produce more than it is rated for, I'm talking about asking a solid amp to make its rated power. I'm not talking about the flea market amps that advertise 1000W but can only really do 150 with acceptable distortion. Whether the 250/1 is hooked up to a 13W7 or a 8W3, asking it to produce 250 watts is no different.

 

[PatFitz9 10+ year member]

didn't you ask this when you first joined here? a watt is a watt. and 250 watts is 250 watts. jacking the gain all the way up on a 250 watt amp isn't the way to get 250 watts. gains aren't volume controls. you can not change anything on the amp, plug in a different HU and different power results.

 

[squeak9798 5,000+ posts]

Honestly cots, just stop posting.

You have an extremely poor understanding of acoustics, including many of the basic fundamentals.

You attempt to engage in technical debates in which you have a complete lack of fundamental understanding. You have absolutely no knowledge of the actual physics surrounding such discussions.

You are severely misinformed at just about every basic level. I have no idea where you gained your "knowledge", but I suggest forgetting everything you "know" and spend some time actually learning about some of the concepts. I likewise suggest you no longer listen to anything your "source" has to say...because they are likewise fundamentally flawed in their level of understanding.

And I have yet to see you make a post on this forum that was factually based. Everything thus far has been either your (completely misinformed) "opinion" and/or just flat out contrary to the physics that are involved.

Stop posting responses to questions. Stop posting "answers". Stop engaging in somewhat technical debates. Just stop.

Read, ask questions, and learn.

But for the love of god...stop "debating" and answering questions with such responses as the fallacies in your logic and your total lack of comprehension of basic physics regarding loudspeakers, amplifiers and acoustics is laughable at best.

 

[T3mpest 10+ year member]

Honestly cots, just stop posting.
You have an extremely poor understanding of acoustics, including many of the basic fundamentals.

You attempt to engage in technical debates in which you have a complete lack of fundamental understanding. You have absolutely no knowledge of the actual physics surrounding such discussions.

You are severely misinformed at just about every basic level. I have no idea where you gained your "knowledge", but I suggest forgetting everything you "know" and spend some time actually learning about some of the concepts. I likewise suggest you no longer listen to anything your "source" has to say...because they are likewise fundamentally flawed in their level of understanding.

And I have yet to see you make a post on this forum that was factually based. Everything thus far has been either your (completely misinformed) "opinion" and/or just flat out contrary to the physics that are involved.

Stop posting responses to questions. Stop posting "answers". Stop engaging in somewhat technical debates. Just stop.

Read, ask questions, and learn.

But for the love of god...stop "debating" and answering questions with such responses as the fallacies in your logic and your total lack of comprehension of basic physics regarding loudspeakers, amplifiers and acoustics is laughable at best.

he's good with buzzwords though Anyway, I'll answer cots last question. Just because a sub is rated for 1000 watts, or an amp is rated for 1000 watts does not mean they need that much power, or will give that much power all the time. At a normal listening level, you won't use much more than a few hundred watts to power your sub, peaks may take more, but even then, it depends on just how high your gains are set vs your hu volume. If set correctly, the preout voltage will never be large enough to ask for more than the amp can cleanly give.

If your listening to music at a low volume level, with gains set correctly, your sub might only need 150 watts at a given point in time. At that moment, a 1000/1 and a 250/1 would both do the same job of powering your w7. Due to you gain structure and listening volume, neither amp would be being pushed to it's limits. Since both amps rated well below 1% distortion at this level, you'll have no audible differences.

Long story short, a bigger amp will allow your speaker to get louder, why? A given preout voltage from your hu is capable stimulating the amp to produce a larger amount of wattage. However, if the amount of power that is being asked of an amp is lower than that of what a given amp CAN give cleanly, then all amps should be adequate in this case.

 

[monkeyboy 10+ year member]

I thought the damping (sp) factor was the ability of an amp to control a load.

If you run a 250W amp with a damping factor of 100 to 250W, and a 1000W amp with the same damping factor to 250W, the distortion is the same, since the damping is the same.

Am I wrong?