Underpowering

[AcidDrag0n]

Is it possible to hurt an amp by underpowering it?

[camaro_speedemon]

Under powering as in not getting enough voltage to it? YES!! This is very bad! Most amps must have ATLEAST 12V. Some even require 13.9 (with the car running)to operate properly. Most newer amps, and high priced amps have a protection circuit that will shut the amp off if it doesn't have enough voltage.
If you mean by underpowering the sub by not having enough watts to push it. YES! This will make the amp peak and put constant voltage to the voice coils causing them to get too hot and burn the coils up.
So all around under powering is bad, and will destroy your equipment.

[RSFireDog]

<blockquote>quote:</font><hr>Originally posted by camaro_speedemon:
Under powering as in not getting enough voltage to it? YES!! This is very bad! Most amps must have ATLEAST 12V. Some even require 13.9 (with the car running)to operate properly. Most newer amps, and high priced amps have a protection circuit that will shut the amp off if it doesn't have enough voltage.
If you mean by underpowering the sub by not having enough watts to push it. YES! This will make the amp peak and put constant voltage to the voice coils causing them to get too hot and burn the coils up.
So all around under powering is bad, and will destroy your equipment.<hr></blockquote>

Thats a big 'ol negative. Unless the amp has a regulating power supply, you will not harm the amp. Even with a regulating power supply, if you are only talking about a volt or two, you will still be good. Worst case scenario is that it will get hot, when it has to compensate for a large voltage loss (Assuming its set for 12V). Most amps do however have thermal protection where they will shut off power if they get too hot, so you should be alright.

If it doesnt have a regulating power supply, then all it means is that you will get an output proporional to your voltage, i.e. 12V = 500watts, 11V = 460watts, etc...

As far as burning up the coils, the amp runs off the voltage, not the distance the speaker moves. If the speaker is only getting 50 watts and is supposed to see 100, the amp is not going to compensate by putting a huge load on the coil and buring it up, rather decreasing the output power to the speaker.

No amps require 13.9V, you are reading the specs and most manufacturers give those because thats what the voltage off your alternator would be if you had a strong alternator. No amps have a protection circuit for 'not enough voltage' All that does, like I said, was decrease output power.

[grndlvl]

<blockquote>quote:</font><hr>Originally posted by RSFireDog:


Thats a big 'ol negative. Unless the amp has a regulating power supply, you will not harm the amp. Even with a regulating power supply, if you are only talking about a volt or two, you will still be good. Worst case scenario is that it will get hot, when it has to compensate for a large voltage loss (Assuming its set for 12V). Most amps do however have thermal protection where they will shut off power if they get too hot, so you should be alright.

If it doesnt have a regulating power supply, then all it means is that you will get an output proporional to your voltage, i.e. 12V = 500watts, 11V = 460watts, etc...

As far as burning up the coils, the amp runs off the voltage, not the distance the speaker moves. If the speaker is only getting 50 watts and is supposed to see 100, the amp is not going to compensate by putting a huge load on the coil and buring it up, rather decreasing the output power to the speaker.

No amps require 13.9V, you are reading the specs and most manufacturers give those because thats what the voltage off your alternator would be if you had a strong alternator. No amps have a protection circuit for 'not enough voltage' All that does, like I said, was decrease output power.<hr></blockquote>

that's correct you wont hurt the amp buy not running to low voltage

[AcidDrag0n]

Damn, i'm a retard guys. I meant will it hurt a subwoofer by underpowering it. Geez :cool:

[RSFireDog]

No it will not all it will do is reduce output power. Read my previous post and you will understand.

[camaro_speedemon]

<blockquote>quote:</font><hr>Originally posted by RSFireDog:


Thats a big 'ol negative. Unless the amp has a regulating power supply, you will not harm the amp. Even with a regulating power supply, if you are only talking about a volt or two, you will still be good. Worst case scenario is that it will get hot, when it has to compensate for a large voltage loss (Assuming its set for 12V). Most amps do however have thermal protection where they will shut off power if they get too hot, so you should be alright.

If it doesnt have a regulating power supply, then all it means is that you will get an output proporional to your voltage, i.e. 12V = 500watts, 11V = 460watts, etc...

As far as burning up the coils, the amp runs off the voltage, not the distance the speaker moves. If the speaker is only getting 50 watts and is supposed to see 100, the amp is not going to compensate by putting a huge load on the coil and buring it up, rather decreasing the output power to the speaker.

No amps require 13.9V, you are reading the specs and most manufacturers give those because thats what the voltage off your alternator would be if you had a strong alternator. No amps have a protection circuit for 'not enough voltage' All that does, like I said, was decrease output power.<hr></blockquote>

I hate to say , but your wrong. My amp has "Protection" with a red LED. What could cause it to go into protection can be a number of things, like not enough voltage, too hot, ect. Trust me, I speak from experience, if you have less than 11V you're amp is toast. I also had an amp that wouldn't turn on if it detected less than 12V.
Your close by saying it will get a little hot....But not quite, it will heat up so quick that even with thermal protection, it would cause damage before it would shut everything down, I have done it before. If you don't know, heat is bad for electronics. They are designed at a certain temperature, if you exceed that temperature, then you are looking at damage to the equipment. What you think a little bit of heat, could actually be death to the amp.

As for under-powering a sub, I got that backwards, I was tired when I posted. Underpowering your subs isn't bad. What I was describing is when you peak or over-power your amp.

And ALL cars run on 13.9V. You must be thinking of amps. Most stock alternaters put out somewhere between 70-120amps normally. All alternaters put out 13.9V when running. It is what your car is designed to run off of.

[RSFireDog]

<blockquote>quote:</font><hr>Originally posted by camaro_speedemon:


I hate to say , but your wrong. My amp has "Protection" with a red LED. What could cause it to go into protection can be a number of things, like not enough voltage, too hot, ect. Trust me, I speak from experience, if you have less than 11V you're amp is toast. I also had an amp that wouldn't turn on if it detected less than 12V.
Your close by saying it will get a little hot....But not quite, it will heat up so quick that even with thermal protection, it would cause damage before it would shut everything down, I have done it before. If you don't know, heat is bad for electronics. They are designed at a certain temperature, if you exceed that temperature, then you are looking at damage to the equipment. What you think a little bit of heat, could actually be death to the amp.

As for under-powering a sub, I got that backwards, I was tired when I posted. Underpowering your subs isn't bad. What I was describing is when you peak or over-power your amp.

And ALL cars run on 13.9V. You must be thinking of amps. Most stock alternaters put out somewhere between 70-120amps normally. All alternaters put out 13.9V when running. It is what your car is designed to run off of.<hr></blockquote>

Amps will NOT go bad if they are underpowered. The voltage on your car is a 12V system, the charging voltage of your alternator is 13.9V. You might know from 'experience' but I know from schooling. Unless you have a voltage regulator, that would make the amp run hot in an overtemp. condition, you will not harm the amp. You say you had an amp that wouldnt turn on if it had less than 11V? Well that's probably true, but are you harming the amp if it isn't on? All that's there for, is if you are running 11V from your battery, you are already pulling close to max current from the alternator. That is a safety to protect your car, not the amp.

As far as you saying that I said 'a little bit of heat'. Read back I did not say that, I said it would get hot and thermal protection would kick in, exactly what you wrote right after I did.

As far as your alternator statement goes, your car is not designed to run off of 13.9V, that is the charging voltage of your alternator. Your car a 12V DC electrical system and everything is designed to run off of 12V DC. The charging voltage of the alternator is 13.9V, meaning if the voltage gets below 13.9V, the alternator turns on. If we had a 13.9V electrical system, don't you think we would have 13.9V batteries and an alternator set to charge at 15+V DC?

Also, alternators don't put out 70-120amps, that is the full capacity of them. Much like your car audio amps don't put out 70amps, even though thats what your fuses or manual say, that is its peak, which 99% of the time you wont hit. If you did, you would be blowing fuses left and right. Alterators work the same way. Also, don't forget that with a current has a positive temperature coeffiecient, meaning as current goes up, temperature goes up. If you were producing a constant 70-120amps, for an hour with an average engine temperature of 180degrees, think about what would happen to the stator windings of the alternator?

Please don't trust 'LED's' on your amp to compare knowledge with. I dont want to sound like an a**, but I know more than you about car audio, so do some more research before you call me out on something.

[camaro_speedemon]

OK, let me explain something, textbook knowlege is like bench racing. You may know more about the equations and formulas but everything I know from car audio is from experience. I haven't looked at a textbook for anything. And I KNOW for a fact that most amps will be damaged under 12V. Why don't you try pounding a few notes wide open gain on an amp with lets say 10V and then tell me how the amp is. The amp will overheat and be damadged before themal protection will kick in. I have seen it happen.
I just did a little research. Most of the amplifires I looked at required atleast 10.5-12V to operate. Most being close to 12V.

As for alternators only turning on when you batter is lower than 12V? Then can you explain why it says on my volt meter on my dash I'm running at 13.9 V? Or how about when I take a volt meter and connect it to the batter when the car is operating? Whenever your engine is running, it is charging. I know that alternaters rating is MAX output amps. And I know that as current increases, so does heat as well as resistance. I am not trying to flame here, but I know that amps require a certain voltage to operate properly.

[RSFireDog]

<blockquote>quote:</font><hr>Originally posted by camaro_speedemon:
OK, let me explain something, textbook knowlege is like bench racing. You may know more about the equations and formulas but everything I know from car audio is from experience. I haven't looked at a textbook for anything. And I KNOW for a fact that most amps will be damaged under 12V. Why don't you try pounding a few notes wide open gain on an amp with lets say 10V and then tell me how the amp is. The amp will overheat and be damadged before themal protection will kick in. I have seen it happen.
I just did a little research. Most of the amplifires I looked at required atleast 10.5-12V to operate. Most being close to 12V.

As for alternators only turning on when you batter is lower than 12V? Then can you explain why it says on my volt meter on my dash I'm running at 13.9 V? Or how about when I take a volt meter and connect it to the batter when the car is operating? Whenever your engine is running, it is charging. I know that alternaters rating is MAX output amps. And I know that as current increases, so does heat as well as resistance. I am not trying to flame here, but I know that amps require a certain voltage to operate properly.<hr></blockquote>

Textbook knowledge is not like bench racing, textbook knowledge is the end all and be all when it comes to electronics. If you just sit there and think that something works because you saw it do something, you are wrong. If you knew anything about electronics you would know that amps WITHOUT regulating power supplies will not be harmed if the voltage goes below 13.9V or 12V. If your theory was correct, you would not be able to run anything while the car was off.

You also said that the amp would heat up before thermal protection would kick in?? I don't even know where you got that from, thermal protection is exactly as it states, THERMAL PROTECTION, if a temperature below the operating range is detected, the thermalresistor senses the high temperature and changes the resistance, and it to make a long story short, it shuts off power.

You also totally contradicted yourself when you said that amps wont operate at lower than 13.9V and 12V, but you researched it and you found that most operate between 10.5V and 12V?

I didnt say that alternators turn on at 12V I said that they keep the charge at 13.9V, and that your cars electrical system is meant to run off of 12V DC. The meter in your car says 13.9V because thats what it is, if you turn off your car and measure voltage you will notice that it is lower.

Also, for you to say that amps wont run off of anything lower than 13.9V, do this: Turn off your car and run your stereo, then tell me what happens first, the battery goes dead, or 'death to the amp' as you put it. Granted you might have a voltage device in your amp, one that has the amp shut off if it doesn't recieve 12V or 11V, but it still wont harm the amp.
Look at older amps that didn't have that device, they wouldn't shut down, they would just have a reduction in power. Voltage is proportional to Power.

For your last statement, about amps require a certain voltage to operate correctly, well you are absolutly correct, if you want to see maximum power gains, you will supply the voltage suggested by the manufacturer. But you will not harm the amp by feeding it a lower voltage.

Real quick, going back to what you said about heat being bad for electronics. Well I don't know about you, but my amps run better when they are warm ;)

[camaro_speedemon]

I'm not going to argue with you anymore, because we aren't really getting anywhere. I know I am right, and you think you are right. I stated I did a little research and found out that required power ranges from 10-12V. I was pulling 12V from the top of my head. I called Maxxsonics, the maker of Crunch, Hifonics, and Maxxsonics. Straight from the mouth of techincal service. I asked him if you needed a constant 12V to the amp and if it was damadging to the amp to run lower his reply "Yes, You need atleast 12V, or it will harm the amp" and I'm pretty sure he knows what he is talking about. I asked my friend who works with electronics, and builds and troubleshoots LED signs, he said the same thing. If you want I can ask the broacast engineers I work with, and I'm sure they will say the same thing as well.

When you turn your car off, you are still running at 12V. If you are trying to say that you can run certain amps at lower voltage than its rated at(if they don't turn off lower than 12V like mine did), you are right, I never said they wouldn't, BUT you will damage the amp if you do. I know thermal sensors turn the amp off, but it's possible to damage something before it reacts. Just think about it, if something is heating up increadabley fast it will still be heating from the time the sensor detects it's too hot, to the time it shuts it off. I don't know exactly how to explain it because I'm not an engineer, I just know its not 100% fool proof.

As for heat being bad for electronics, it is. The reason you amps work better warm is they are probably designed to most efficient at a certain temperature. Most electronics are designed to operate within a temerature range. If you were run it cooler and have it designed to run cooler, it would probably function better. Heat=resistance. Less heat, less resistance, more efficient. More heat, more resistance, less efficient. ;)
When you get down to FL, we should meet up sometime, I'm just 50 miles north of Sarasota, I think we would have some interesting conversations. [img]tongue.gif[/img]

[RSFireDog]

Yo're friend is wrong. That is unless the amps they are talking have regulating power supplies.

I want to spell this out as easily as I can, so bear with me here..

If your amp has a regulating power supply, underpowering it will be harmful.

If your amp does not have a regulating power supply, you could run 1V to it, and it would be fine. You will not damage the amp, if you run a lower voltage than 12V DC.

Your friends that you called might have thought you were talking about an amp with a regulating power supply, but not all have those, so clarify next time. If you did that already, and your friends and techs at hifonics said that, then they are pretty stupid. Amps don't work like that. When I come back to Florida, if you want I'll bench check an amp with a 5V PSU and I'll show you how it doesn't harm the amp.

Also, please stop trying to insinuate that you are smarter than me and that you know more than me about electronics, its starting to irriatate me.

Thanks.

[camaro_speedemon]

I'm not trying to insinuate that I am smarter than you in electronics, because I honestly don't know a lot, I know enough to get myself in trouble. If I came across that way, I didn't mean to. All the amps that I have delt with I know that it was harmful to go under 12V. I have no clue what kind of power supply they had. As you said if they had a regulating power supply then I was correct in saying it would be damaging to the amp. You could have clarified yourself in stating that a regulating PS needs xxV to operate, BUT a non regulating PS doesn't, as you did in your last post. I don't even have a clue what the difference between them is. Probably something to do with regulating power ;) I know the basic concept is to convert 12V DC to xxV AC, at least thats what was explained to me. Thats about as much as I know. So technically I was right and wrong. I don't have a problem admitting I am wrong.

[TransNot]

Wow that was the most fun I've had reading two people argue about something they both are sure they're right on. Anyway, in case there's any question left about if underpowering an amp (as long as it's non-regulated or whatever), it won't hurt it at all. I had my stereo playin with my car off til the battery died once :rolleyes: ... I think i was on crack that day. Anyway, I got a jump and the amp was just as good and loud as ever.

This is also speaking from niether experience nor book-smarts. ;)

[ January 19, 2003: Message edited by: TransNot ]</p>

[MrCoffee]

after reading 2 articles over at howstuffworks.com, I have come to the conclusion that it wont hurt an amp to underpower it. Transistors and capacitors are 2 main components of an amp. Basically, you can an input signal and the amp amplifies it by a percentage, directly based on the incoming power...

but none of this matter since the post was about subwoofers!