How much Power is to much Power

[Jeffdachef 5,000+ posts]

Understood, but in the above example, what happens at 1 ohm resistance when the amplifier is dumping 1000 watts of energy into a voice coil rated at 500 watts root mean square? Curious.
Am I misunderstanding something? Kindly advise.

you never ever see 1 ohm unnless you have a resistive load on a test bench like the Amplifier dyno. The RMS rating of the subwoofer is on an actual 500 watts after impedance rise Like for example the sundown woofer rated for 500 watts thats 500 watts after impedance rise a true clamped 500 watts for hours on end without failure. Most normal people dont understand rise because you guys never competed in power restricted classes where they clamp test for true real world power to make sure you are in your class. You are NEVER getting the power you think you are getting. Its always WAAAAAAAAy less.

So would it be acceptable to run 825 watts at 4 ohms ( Zapco Reference 1100M) to a 500 watt rms (Audiofrog GB12 4 ohm subwoofer) The peak dynamic power of the Zapco 1100.1 is 1625 watts, not sure of the Audiofrog GB12.

You dont look at peak dynamic power, only RMS and certified numbers on the amp dyno. That audiofrog would be slightly underpowered because the lowest impedance you'll see is around 8 ohms and higher on music at best you'll see 300ish actual real world power if you arent soft clipping it.
You also need to look at it this way. An amp operating at 80% capacity vs one being redlined at 100 to 110% which amp will run cooler, more efficient vehicle voltage wise with cleaner power, lower distortion and longer life span?

 

[JTF Vegas]

you never ever see 1 ohm unnless you have a resistive load on a test bench like the Amplifier dyno. The RMS rating of the subwoofer is on an actual 500 watts after impedance rise Like for example the sundown woofer rated for 500 watts thats 500 watts after impedance rise a true clamped 500 watts for hours on end without failure. Most normal people dont understand rise because you guys never competed in power restricted classes where they clamp test for true real world power to make sure you are in your class. You are NEVER getting the power you think you are getting. Its always WAAAAAAAAy less.


You dont look at peak dynamic power, only RMS and certified numbers on the amp dyno. That audiofrog would be slightly underpowered because the lowest impedance you'll see is around 8 ohms and higher on music at best you'll see 300ish actual real world power if you arent soft clipping it.
You also need to look at it this way. An amp operating at 80% capacity vs one being redlined at 100 to 110% which amp will run cooler, more efficient vehicle voltage wise with cleaner power, lower distortion and longer life span?

Even with the above Zapco?

 

[JTF Vegas]

you never ever see 1 ohm unnless you have a resistive load on a test bench like the Amplifier dyno. The RMS rating of the subwoofer is on an actual 500 watts after impedance rise Like for example the sundown woofer rated for 500 watts thats 500 watts after impedance rise a true clamped 500 watts for hours on end without failure. Most normal people dont understand rise because you guys never competed in power restricted classes where they clamp test for true real world power to make sure you are in your class. You are NEVER getting the power you think you are getting. Its always WAAAAAAAAy less.


You dont look at peak dynamic power, only RMS and certified numbers on the amp dyno. That audiofrog would be slightly underpowered because the lowest impedance you'll see is around 8 ohms and higher on music at best you'll see 300ish actual real world power if you arent soft clipping it.
You also need to look at it this way. An amp operating at 80% capacity vs one being redlined at 100 to 110% which amp will run cooler, more efficient vehicle voltage wise with cleaner power, lower distortion and longer life span?

My understanding was that old school Zapco amplifiers were underated. I was told it could run 1200 all day long with no issues. Curious.

 

[stephgirl]

you never ever see 1 ohm unnless you have a resistive load on a test bench like the Amplifier dyno. The RMS rating of the subwoofer is on an actual 500 watts after impedance rise Like for example the sundown woofer rated for 500 watts thats 500 watts after impedance rise a true clamped 500 watts for hours on end without failure. Most normal people dont understand rise because you guys never competed in power restricted classes where they clamp test for true real world power to make sure you are in your class. You are NEVER getting the power you think you are getting. Its always WAAAAAAAAy less.


You dont look at peak dynamic power, only RMS and certified numbers on the amp dyno. That audiofrog would be slightly underpowered because the lowest impedance you'll see is around 8 ohms and higher on music at best you'll see 300ish actual real world power if you arent soft clipping it.
You also need to look at it this way. An amp operating at 80% capacity vs one being redlined at 100 to 110% which amp will run cooler, more efficient vehicle voltage wise with cleaner power, lower distortion and longer life span?

But the other question was about the mid and tweeter. What about that rise and how must on those speakers. Do they have the same as a sub would or less? And thats true that most would not understand rise because most don't compete in power class shows, but it is good to reserch and learn and understand this stuff so when you go out to purchase that sound system say for you daily driver you can buy speakers and amps that work good and get the best bang for your bucks.

 

[Louisiana_CRX 5,000+ posts]

WOW n2audio that name Richart Clark sound familiar. I can remember back in 90's when i worked at the GM car dealership here in So Cal and a few of us service technicians that were into car audio used to read Car Audio Magazine. What i remember was this guy who was a expert car audio person and sound tech guy and had articles or where written about him articles on system setups from amps specs to speakers and speaker placement and so on. I think he was affiliated with or worked out of a shop called Speaker Works in Orange California. To this day the one thing that stands out in my mind was this guy said in an article that, if you had to install an equalizer unit in your car to adjust the sound for sound shaping or volume your system was not set up correct and the amp power and speaker placement was not right. On the amps I think he was refering to amps also not having enough power to the speakers. That now i understand what he means and what we have been disusing. At the time i think it was a Buick Regal car he was showing. We all remember the EQ units many used to install in the cars back then for more volume and sound. This guy had no equalization in the car and it rocked. I wonder if this is the same guy? wow dating myself.

Speaker Works turned out a lot of nice vehicles in which many were featured in car audio magazines and they took top honors at many of the car stereo events from the late 80's to early 90's a couple of brothers and their dad ran the he place ...one of their brands were USD back in the day .

 

[Jeffdachef 5,000+ posts]

My understanding was that old school Zapco amplifiers were underated. I was told it could run 1200 all day long with no issues. Curious.

we dont know its true ratings unless you do a clamp test or amp dyno.

But the other question was about the mid and tweeter. What about that rise and how must on those speakers. Do they have the same as a sub would or less?

They have less since the coils travel a lot less. Impedance rise happens when a coil travels through a motor and in a sub you have a lot of movement depending on the Xmax. Mids and tweets, not even a fraction of that kind of movement means a lot less rise.

I wouldnt worry too much about overpowering mids and tweeters, They have a tendency to have a sharp spike in the frequency response when the speaker is stressed and has clear signs to back down the gain. Plus you only need enough to get proper output for your listening needs. You dont need to max out the output of the amp just so you can max out the amp which leads to much higher THD vs an amp with headroom which leaves you in the clear almost non existent THD levels if you are only using 80% of the amp or less. Your noise floor, efficiency and everything will be better.

 

[JTF Vegas]

we dont know its true ratings unless you do a clamp test or amp dyno.

They have less since the coils travel a lot less. Impedance rise happens when a coil travels through a motor and in a sub you have a lot of movement depending on the Xmax. Mids and tweets, not even a fraction of that kind of movement means a lot less rise.

I wouldnt worry too much about overpowering mids and tweeters, They have a tendency to have a sharp spike in the frequency response when the speaker is stressed and has clear signs to back down the gain. Plus you only need enough to get proper output for your listening needs. You dont need to max out the output of the amp just so you can max out the amp which leads to much higher THD vs an amp with headroom which leaves you in the clear almost non existent THD levels if you are only using 80% of the amp or less. Your noise floor, efficiency and everything will be better.

So can it be said that Impedance Rise is synonomous with Back Voltage, aka Counter EMF? I understand the very fundamentals of Electromagnetic Induction.

 

[stephgirl]

we dont know its true ratings unless you do a clamp test or amp dyno.

They have less since the coils travel a lot less. Impedance rise happens when a coil travels through a motor and in a sub you have a lot of movement depending on the Xmax. Mids and tweets, not even a fraction of that kind of movement means a lot less rise.

I wouldn't worry too much about overpowering mids and tweeters, They have a tendency to have a sharp spike in the frequency response when the speaker is stressed and has clear signs to back down the gain. Plus you only need enough to get proper output for your listening needs. You dont need to max out the output of the amp just so you can max out the amp which leads to much higher THD vs an amp with headroom which leaves you in the clear almost non existent THD levels if you are only using 80% of the amp or less. Your noise floor, efficiency and everything will be better.

Ok makes sense. So then like a 100rms speaker and say a 150 rms amp will power that speaker just fine. And do to less rise that 150 rms amp most likely would be putting out something like 100w anyway do to less rise. That 150 amp would not see a drop in power to much if it is say powering mids or tweeters only. There would not be as much drop in power do to rise as a sub amp would see. Like the example in the above post, That 1000w amp powering that 500w sub, that amp would only be seeing like 400w do to bigger rise and that bigger motor movement. So like n2audio said in his post, 150-200% is the sweet spot. 100w speaker = 150 - 200w amp or a 500w sub =1000 w amp that would be a good general rule then ?

 

[Bobbytwonames 5,000+ posts]

They led me right when I joined the site. My sub is rated at 1,500 rms. The people here told me, repeatedly, Taramps MD3K. I finally gave in and bought the Taramps. Gain is a round 40% on the amp. My electrical is very limited also. 95 amp alternator, big three, and one extra battery. 2-1 power to rms seems to be nice and safe.

 

[stephgirl]

 

[Jeffdachef 5,000+ posts]

Ok makes sense. So then like a 100rms speaker and say a 150 rms amp will power that speaker just fine. And do to less rise that 150 rms amp most likely would be putting out something like 100w anyway do to less rise. That 150 amp would not see a drop in power to much if it is say powering mids or tweeters only. There would not be as much drop in power do to rise as a sub amp would see. Like the example in the above post, That 1000w amp powering that 500w sub, that amp would only be seeing like 400w do to bigger rise and that bigger motor movement. So like n2audio said in his post, 150-200% is the sweet spot. 100w speaker = 150 - 200w amp or a 500w sub =1000 w amp that would be a good general rule then ?

yup pretty much. Because you want enough power to power your speakers fully without clipping but ALSO to keep your amp as FAR away from any form of THD levels as possible. It actually makes a pretty big difference. Your overall sound is a lot smoother at higher volumes. Vs a weaker amp being redlined, your speakers will start to sound like complete **** way sooner.

 

[wew lad 5,000+ posts]

Considering how cheap amps like the ds1200x4 are it's a no brainer to get something that outputs more power than you need.

For whatever reason the first one I got was problematic with a blown channel and they **** to repair due to how small the IC's are but for the price it's worth the risk. A single channel on it is enough to drive two exodus anarchy's to their limit lol they can only handle about 150w each but still, 300w-400w per channel is absurd.

 

[stephgirl]

So I now have a better understanding of what rise is in speakers and how it effects everything, and a better understanding how to match an amp to a speaker. I think the old misconception to a lot of people was to match a amps watt rms to the speakers watt rms rating but that not the case. Think a lot of us including me have a pretty good knowledge of most of car audio basics but it is the deeper stuff that like engineers and electronic that most don't understand and it's good to know that stuff. When i found this web site and joined back in 2014 i had not dealt in car audio in about 10 years, lot had changed. I had learned that this was a great web site to learn stuff and find out good info on equipment. I was introduced to car audio back in the 90's at the Chevy, Cadillac dealer i worked at as a tech. I was asked to manage the Tire & Accessories dept they had there. Also some of my friends started having sound systems installed in there vehicles. At the Chevy dealer we did the lowered 4-6 dropped trucks with Boyd and Centerline wheels back then. We only did basic sound system stuff back then do to the warranty issues and all. Then i went on to work on my own vehicle and helped a few friends off and on over the years.

So thanks to all who have posted here on this thread and added to the discussion, very informative. Please don't let this thread end. If someone has more to add please do. I hope this could be a thread that newbies should read and understand what impedance rise is when they join here.

I have to say that I really appreciate most of you on here and how you genuine want to inform and help others with car audio info or questions. I know that some of the newbies on here can be hard headed and don't appreciate the help but i think most do. The beauty of this web site is that everyone with there own level of car audio knowledge or even experience can comment and maybe help someone with a question or some experience with a brand or equipment they have. As all know car audio is subjective. I have always tried to look at the positive and see how a post or thread can benefit me. Then i have to be honest and say that there are some on here that are just jerks and just attack and call people all kinds of stuff and put downs, but i get it. Even me, yes me, has even been attacked for even being here on this website. I don't know if i am the only female on here but, i like car audio.

p.s i have a few more question so watch for them

 

[JTF Vegas]

"I think the old misconception to a lot of people was to match a amps watt rms to the speakers watt rms rating but that not the case"

As long as its clear though, that like all things in life, there are limits. Furthermore, if those limits are exceeded, then the system,(whatever that system may be, electronics, nature etc..) will either partially or completely fail.