#259765 - 05/07/2005 19:34
Speaker and Amp power ratings
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carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
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I'm confused about speaker ratings and amplifier ratings and how they interact. Some pages say your speakers should be rated higher than your amp. Other pages say that your amp should be rated higher than your speakers. Both of these cannot be true. Let's start with why we're concerned about this at all. I think we all understand that a higher rated amp is going to be able to produce a louder sound than a lower rated one (assuming their ratings are equivalently determined). And a higher-rated speaker probably performs the same way. So in the best of all worlds, we'd all get amps and speakers with massively high ratings and be done with it. But economics kicks in. I know Doug will pipe up and say that higher power ratings means more headroom, which is likely to mean a cleaner output, which I'm all happy to agree with, but that doesn't help me if I'm trying to reduce cost, and therefore reducing power rating. And what we're interested in mostly with this line of questioning is preventing damage to this equipment. Once we determine how to mix numbers we can approach quality. So, what causes damage? The obvious one is clipped waveforms, which have much more power than unclipped waveforms. What causes clipping? Assuming I don't go over 0dB on the empeg, the source isn't clipping, so it must happen somewhere in the amp or speakers. But it's unlikely that your amp (unless it's really cheap) is causing clipping on its own, I think, so it must be some interaction of the speakers and amp (since the speaker itself is obviously not able to cause it). Some would argue that an underpowered amp causes this, as the high-powered speakers try to draw more power than the amp could handle, like hooking up a bunch of space heaters to one power outlet in your home. This could be a bad analogy because the amp varies voltage while your house does not (not to mention the whole AC/DC thing). Others would argue that an overpowered amp causes it, like a power surge hitting your delicate computers. Maybe both of those are true. One page argues that if your speakers are rated way higher than your amp, then even if the signal is clipped that it won't be able to produce enough power to actually damage them. I suppose now is where we get into quality, as that begs the question that even if the speakers won't be damaged, they won't sound good, and is it the high power rating of the speaker contributing to the clipping? What other causes are there for speaker damage? Overdriving, causing mechanical damage to the coil, surround or cones? What causes this? It would seem that that would be caused by the speaker trying to generate sound louder than it is able to. That would seem to be caused by an overpowered amp. (Obviously the amp would have to be "told" to produce that much volume by turning up the volume on the source.) Here's another question: what causes a change in volume? Is it voltage? Variation in voltage is what describes the waveform, right? And speakers are designated to be of specific impedances. Is there a set voltage maximum for audio systems or is it that 4V specifies the max deflection of the speaker cone in one speaker, but only halfway in another? Or is current a variable, too? But the waveform voltage doesn't specify volume directly. It's the degree of variation in the waveform that's volume. That is a sinus waveform that travels between 3V and 4V wouldn't be very loud, but one that travels between -4V and 4V would be, despite that its additive value would be zero. Of course, that -4V to 4V sinus wave at 200Hz isn't going to seem as loud as a -4V to 4V sinus wave at 5000Hz. I see now that audio signals are actually AC, aren't they? And you get into power factors with all of this, and not even linear ones, which makes all of this numbering even more complicated than I thought. Okay, now I'm in too deep, and I just want someone to tell me if I need speakers more powerful than my amp, or speakers less powerful, or that they should be the same, or that I should just go stick my head in a Gramophone just to keep my brain from turning to goo with all this confusing information. And please show your work. There's more than enough conjecture without any basis. Hell, there's a lot of inconclusiveness pretending to be an answer. To be honest, I don't really care that much about the math, but there are obviously a lot of people out there just repeating what they've heard, so I need some basis for a conclusion now. (That is, if everyone said "your speakers need to be rated at 1.414 times your amps rating", I wouldn't really care about any basis, but as it is, that 1.414 can be replaced by anything from one-tenth to ten and it seems that someone will agree with it.)
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Bitt Faulk
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#259766 - 05/07/2005 20:30
Re: Speaker and Amp power ratings
[Re: wfaulk]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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All very good questions.
Some of them are answered here, and I suspect at least some of the others are answered elsewhere at that site, but you might have to sift through a lot of pages to find them all.
Edit: Yeah, some other pages here and here...
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#259767 - 05/07/2005 20:41
Re: Speaker and Amp power ratings
[Re: tfabris]
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carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
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That site in particular is in opposition to most of the other sites, and, in fact, was one of the sites linked in my post.
They state that the speakers should have higher ratings than the amp. But, despite all the math throughout the site, they don't seem to actually have much data to back up that assertion. If I'm wrong, please show me what I should be looking at.
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Bitt Faulk
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#259768 - 05/07/2005 21:14
Re: Speaker and Amp power ratings
[Re: wfaulk]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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Sorry, I checked two of your three links....  Here's my opinion on the topic, sort of distilling what the guy at that site said: Power doesn't kill, misuse of power does. So. If your amp is underpowered, and you want it louder, so you crank the volume so hard that the amp's input signal is overdriven, then you cause clipping, which is Bad. If your amp is overpowered, and you inadvertently turn things up loud enough so that it causes too much energy to go through the speaker's voice coils, thus causing the speaker to clip or the voice coils to overheat, then that is also bad. I'm not sure which is worse or which is more likely to blow a speaker.
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#259769 - 05/07/2005 23:50
Re: Speaker and Amp power ratings
[Re: tfabris]
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carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
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I suppose that's a good point. Too much power can overdrive the speakers and too little power makes you want to crank it.
So the answer may be to get a (slightly) underpowered amp and make sure to set your speakers to not clip at the maximum volume on the empeg.
I think traditional thought would tell you to basically do that anyway, substituting "clip" with "burst your eardrums" at some point.
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Bitt Faulk
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#259770 - 06/07/2005 08:44
Re: Speaker and Amp power ratings
[Re: wfaulk]
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pooh-bah
Registered: 02/06/2000
Posts: 1996
Loc: Gothenburg, Sweden
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Quote:
I'm confused about speaker ratings and amplifier ratings and how they interact.
Some pages say your speakers should be rated higher than your amp. Other pages say that your amp should be rated higher than your speakers. Both of these cannot be true.
When in doubt I'd with the Basic car audio electronics site. Haven't seen anything there that goes against my education and experiences while here's a lot of BS and voodoo spouted out there.
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Let's start with why we're concerned about this at all. I think we all understand that a higher rated amp is going to be able to produce a louder sound than a lower rated one (assuming their ratings are equivalently determined).
Yes
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And a higher-rated speaker probably performs the same way. So in the best of all worlds, we'd all get amps and speakers with massively high ratings and be done with it. But economics kicks in.
Not the power ratings - they just state how much power the speaker can handle. How loud it'll be depends on the sensitivity of the speaker, expressed as a dB rating per watt and meter (dB measured at 1 meter distance with 1 watt power applied).
That and how much power the speaker he how handle will give how loud it can be. THeoretically every doubling of power will give you +3dB. For a perceived doubling in volume, a factor 10 in power is required.
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So, what causes damage?
The obvious one is clipped waveforms, which have much more power than unclipped waveforms. What causes clipping? Assuming I don't go over 0dB on the empeg, the source isn't clipping, so it must happen somewhere in the amp or speakers. But it's unlikely that your amp (unless it's really cheap) is causing clipping on its own, I think, so it must be some interaction of the speakers and amp (since the speaker itself is obviously not able to cause it).
Background: The amp has an internal power supply that pumps up the voltage above 12V in order to be able to give more power. Power is proportional to voltage squared and inverse proportional to resitance/impedance P=U^2/R.
I see clipping happening from 2 causes:
: Asking the amp to deliver a voltage on the output higher than the supply voltage. This happens from the combination of input signal voltage and gain setting. While normally labelled in sensitivity (ie how much input voltage is required for max on the output) it really sets the multiplication factor between input and output voltage.
When input*gain > max possiblevoutput, the utput will simply remain at the max possible...
Second is asking the amp to deliver more current han the supply can give. Typically running a too low impedance load. Tooo much current drawn will likely cause the voltage from the suppply to also drop - then see above.
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Some would argue that an underpowered amp causes this, as the high-powered speakers try to draw more power than the amp could handle, like hooking up a bunch of space heaters to one power outlet in your home. This could be a bad analogy because the amp varies voltage while your house does not (not to mention the whole AC/DC thing).
No, a higher powered speaker, of the same impedance (typical 4 Ohm), will NOT draw any more current than a lower power rated one. urrent is solely determined by amp output voltage and the speaker impedance I=U/R. Voltage times current gives power P=U*I. Combine those and yuo see that P=U^2 / R (or P=I^2 * R) A higher rated speaker can just withstand/dissipate more power. It's just like resistors - despite being the same Ohm value, depending on construction and size they can handle different amounts of power.
Hooking up to many/too large heaters in your house will result in a a current draw larger than your fuses (because the total resistance of the heater(s) is too low) and/or house wiring can handle. Hooking up a higher power rated speaker (with the same impedance) will make no difference at all. Hooking up multiple in parallell will lower the total impedance the amp 'sees' and the current will increase, posibly above what the internal power supply can handle (clipping) or what the output transistors can handle (going up in smoke)
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Others would argue that an overpowered amp causes it, like a power surge hitting your delicate computers.
An underpowered amp is likelier to run into the limitations above, if you ask too much from the amp, in a desire for more volume...
ncw
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Maybe both of those are true. One page argues that if your speakers are rated way higher than your amp, then even if the signal is clipped that it won't be able to produce enough power to actually damage them.
I'd agree. The difference in power between a sine wave and a square vawe of the same amplitude (top output voltage) is a factor 2 (Calculate the areas (integrate) of a halfperiod and you'll see a factor of sqrt(2), and since power is a function of voltage squared, we get sqrt(2)^2=2)
If the speaker can handle way more than that, I see no cause for alarm - except for it sounding like crap due to the speaker playing a square vawe signal..
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I suppose now is where we get into quality, as that begs the question that even if the speakers won't be damaged, they won't sound good, and is it the high power rating of the speaker contributing to the clipping?
And the fuzzy marketing factor in ratings of car audio stuff, either for the imponator effect "Look at my 1600W amp" (a right bargain at only 89.95 on eBay...) or brand reputation - Acme speakers can handle more than rated / Acme amps delivers more than rated - must be good stuff...
But the power rating does NOT contribute to clipping. A too low impedance could.
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What other causes are there for speaker damage? Overdriving, causing mechanical damage to the coil, surround or cones? What causes this? It would seem that that would be caused by the speaker trying to generate sound louder than it is able to. That would seem to be caused by an overpowered amp. (Obviously the amp would have to be "told" to produce that much volume by turning up the volume on the source.)
Yes, to high a voltage will mean the speakers tries to move further than the designer anticipated. Too much and something will break. Keping within the outright breaking things limit, stuff can get too hot over a period of time, typically causing glue to fail, plastics to weaken/deform/melt, insulating laquer on the coil wire to burn off, causing shorts between turns of the coil -> lower impedance -> more current -> more heat...
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Here's another question: what causes a change in volume? Is it voltage? Variation in voltage is what describes the waveform, right?
Yes. and variation in voltage is what eventually (by causing a current to flow, causing a magnetic field in the coil) causes the coil/membrane to move. More chaange in voltage gives larger movement of the coil/embrane, meaning more air moved, meaning your eardrum moves more, ie louder.
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And speakers are designated to be of specific impedances.
Yes. Car speakers typically 4 Ohm, though subs vary more, for higher power ability and flexibility in wiring multiple subs.
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Is there a set voltage maximum for audio systems or is it that 4V specifies the max deflection of the speaker cone in one speaker, but only halfway in another?
A given voltage will cause different deflection in different speakers. Somewhat described by the sensitivity rating of the speaker (a dB number measured at 1 meter with 1 watt power to the speaker. Power and voltage relates according to P=U^2 / R.
Then again different speakers have differing max deflections.
The space in a HU is rather limited, giving litle/no room for a power supply to crank up tthe internal voltage, limiting most HUs to bout the same real power, despite various claims.
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Or is current a variable, too?
For a given speaker, current varies according to amp output voltage and speaker impedance.
Power is ultimately given by voltage times current, but given voltage and impedance we need not explicitly calculate/measure current as it's a given from voltage and impedance.
A lower impedance speaker will tickle more power from an amp (within limits). An amp might be rated at 75W @ 4 Ohm and 150W @ 2 Ohm. Theoretically running a 1 Ohm load would give 300W, but we're likely to run into limits of the power supply and/or the output transistors.
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But the waveform voltage doesn't specify volume directly. It's the degree of variation in the waveform that's volume. That is a sinus waveform that travels between 3V and 4V wouldn't be very loud, but one that travels between -4V and 4V would be, despite that its additive value would be zero.
Yes, the variation in voltage drives the motion of the coil/membrane. The variation is called amplitude, in your example 1V and 8V (peak to peak) the average from 0 is the DC offset, 3.5V and 0.
DC offset moves the 'resting point' of the coil/membrane but and causes heat to be developed in the coil but, doesn't contribute to volume.
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Of course, that -4V to 4V ssinus wave at 200Hz isn't going to seem as loud as a -4V to 4V sinus wave at 5000Hz.
Because the ear is less sensitive to lower frequencies. The coil/membrane still moves just as much (possibly ignoring any limiting effects from mass/inertia).
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I see now that audio signals are actually AC, aren't they?
Yes
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And you get into power factors with all of this, and not even linear ones, which makes all of this numbering even more complicated than I thought.
For most calculations power factor /phase angle can be ignored...
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Okay, now I'm in too deep, and I just want someone to tell me if I need speakers more powerful than my amp, or speakers less powerful, or that they should be the same, or that I should just go stick my head in a Gramophone just to keep my brain from turning to goo with all this confusing information.
I'd say go with roughly the same ratings and be sensible with the gain setting, trust your ears.
'm using a 6x75W amp; front system is rated to 50W, rear speakers to 80W and the sub 250W (runs of 2 channels bridged, which should give 300W)
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And please show your work. There's more than enough conjecture without any basis. Hell, there's a lot of inconclusiveness pretending to be an answer. To be honest, I don't really care that much about the math, but there are obviously a lot of people out there just repeating what they've heard, so I need some basis for a conclusion now. (That is, if everyone said "your speakers need to be rated at 1.414 times your amps rating", I wouldn't really care about any basis, but as it is, that 1.414 can be replaced by anything from one-tenth to ten and it seems that someone will agree with it.)
I'd be happy to go deeper, but it's a lot easier in person/on paper than using a keyboard.
If there's anything specific to something I've said, ask and I'll try try to expand.
_________________________
/Michael
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#259771 - 06/07/2005 13:44
Re: Speaker and Amp power ratings
[Re: mtempsch]
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carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
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Wow. Thanks for the very complete response. A couple of questions and points: Quote:
A higher rated speaker can just withstand/dissipate more power. It's just like resistors - despite being the same Ohm value, depending on construction and size they can handle different amounts of power.
That's a great point. I'd never thought of it like that, but it makes a hell of a lot of sense. Pretty much tosses out the notion that higher-power-rated speakers demand more power than lower-rated ones.
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The amp has an internal power supply that pumps up the voltage above 12V ... I see clipping happening from 2 causes:
: Asking the amp to deliver a voltage on the output higher than the supply voltage.
Well, if the amp is intentionally delivering more voltage than 12V, which is what the car is supplying, doesn't that mean that you always run that risk? Or do you mean more voltage than the power supply is able to generate?
And assuming that the speakers are 4Ohms, that means that the power rating of an amp directly tells you how much voltage it can produce by taking the square root of four times the power rating. So a 75W amp can produce up to 17.3V and a 300W amp can produce up to 34.6V. Of course, nothing's rated in voltages, but that at least helps me get my mind around it.
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Second is asking the amp to deliver more current han the supply can give. Typically running a too low impedance load.
But virtually all car speakers are 4Ohm, right? So that's a non-issue unless you get a non-standard speaker or the speaker becomes damaged some other way first.
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If the speaker can handle way more than that, I see no cause for alarm - except for it sounding like crap due to the speaker playing a square vawe signal..
So that means that, since a high-rated speaker doesn't put any more strain on an amp than a low-rated one, and since a more-than-double-rated speaker should be able to handle the worst case from the amp, then the safest thing to do is get speakers that are rated more than two times the amps rating, yes? Ignoring playing sane volumes and economics.
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I'd say go with roughly the same ratings and be sensible with the gain setting, trust your ears.
'm using a 6x75W amp; front system is rated to 50W, rear speakers to 80W and the sub 250W (runs of 2 channels bridged, which should give 300W)
So even with all this stuff that tells you that speakers can get damaged when they can't handle the power that the amp sends to them, you still run your fronts and subs with under-rated speakers. That tells me that setup and sanity are probably bigger factors than most of this anyway.
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Bitt Faulk
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#259772 - 06/07/2005 14:46
Re: Speaker and Amp power ratings
[Re: wfaulk]
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veteran
Registered: 01/10/2001
Posts: 1307
Loc: Amsterdam, The Netherlands
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Quote:
But virtually all car speakers are 4Ohm, right?
Only on paper. They are not resistors, but complex (mostly inductive) loads - the impedance ("complex resistance") varies with frequency. Some speakers have a fairly flat curve, others have a curve that resembles the Swiss Alps. Thus some speakers are "harder to drive" than others.
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#259773 - 07/07/2005 00:06
Re: Speaker and Amp power ratings
[Re: wfaulk]
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old hand
Registered: 01/10/2002
Posts: 1039
Loc: Fullerton, Calif.
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But virtually all car speakers are 4Ohm, right? So that's a non-issue unless you get a non-standard speaker or the speaker becomes damaged some other way first.
Funny, I thought they were all 8 ohms, but Boston Acoustics web page lists some as 3 ohms. I'm sure the 8 used to be the standard years ago.
Also, some folks will parallel (or even series) speakers together, which changes impedance.
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#259774 - 07/07/2005 00:59
Re: Speaker and Amp power ratings
[Re: larry818]
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veteran
Registered: 01/10/2001
Posts: 1307
Loc: Amsterdam, The Netherlands
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Funny, I thought they were all 8 ohms, but Boston Acoustics web page lists some as 3 ohms. I'm sure the 8 used to be the standard years ago.
Well, there were at least 3 "standard" impedances, 4, 8 and 16 ohm. Old valve gear, with high voltages but low current drive capability, prefers high impedance - that's why the classic BBC 3/5A was 16 ohm. For car systems that work off 12V, lower impedances are better - but if you go too low, your cable resistance starts to influence things too much - the reason old whole-building PA/muzak systems used hundreds of ohms (and volts!).
Most modern hifi speakers are (nominally) between 4 and 8 ohm.
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#259775 - 12/07/2005 09:42
Re: Speaker and Amp power ratings
[Re: wfaulk]
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pooh-bah
Registered: 02/06/2000
Posts: 1996
Loc: Gothenburg, Sweden
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Just back from Amersfoort and only around 300 messages to catch up on, ya'll disappoint me  Quote:
That's a great point. I'd never thought of it like that, but it makes a hell of a lot of sense. Pretty much tosses outt the notion that only higher-power-rated speakers demand more power than lower-rated ones.
Just to play both sides  : a higher rated speaker might be mechanically stiffer and/or less efficient, therefore requiring a bit more power to get as loud as a more efficient, 'easier to drive', speaker. Looking at the efficiency numbers can be interesting. 3dB less sensitive and you need 2x the power for the same volume... But the higher rated speaker still wouldn't "suck" more out of the amp. It just does as well it can with the power delivered.
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If the amp is intentionally delivering more voltage than 12V, which is what the car is supplying, doesn't that mean that you always run that risk? Or do you mean more voltage than the power supply is able to generate?
Sorry, should have been clerarer - More than power /higher voltage than the power supply can generate.
The internal supply goes to two power rails. Imagine them as roof and floor. The output transistors are connected to these and can make the output any voltage inbetween, but the roof and floor [minus losses in the transistors] are the limit for the voltage on the speaker outputs. Ask the peak voltage of the output, due to input signal level and gain setting, to swing into the sattic and basement and it just won't happen; for the 'tallest' parts of the signal it will just peg to roof or floor.
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And assuming that the speakers are 4Ohms, that means that the power rating of an amp directly tells you how much voltage it can produce by taking the square root of four times the power rating. So a 75W amp can produce up to 17.3V and a 300W amp can produce up to 34.6V. Of course, nothing's rated in voltages, but that at least helps me get my mind around it.
Internally it is likely to be a touch higher in order to give a bit of margin and for some internal losses, such as the saturation voltage (voltage that will still be across the transistor even while we tell it to be fully "on") of the output transistors.
But yes, playing a 0dB (and beware of any filters) 50/60 Hz sinewave and measuring the voltage on the speaker terminals is a way of checking how much power it really makes.
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But virtually all car speakers are 4Ohm, right? So that's a non-issue unless you get a non-standard speaker or the speaker becomes damaged some other way first.
As others have said, most normal car speakers today are 4 Ohm. There are exceptions - for instance some 'premium' OEM packages run lower ohm speakers (with amps designed for it).
The Ohm rating is nominal.
If you measure the DC resistance with a meter, you'd probably be around 3.5 Ohmfor a "4" Ohm speaker.
As you feed it an AC signal, a mainly reactive component (due to the coil) gets added and the total impedance is around 4 Ohm, but may vary some with frequency.
Subwoofers, specially in the upper power ranges, are less standard, I know there are [nominal] 1, 2, 3, 4, 6 and 8 Ohm [per coil] subs - look hard enough and you can probably find other values as well. Mainly as a way to get the number of subs you want and a final load suiting the amp. For 3 subs and a 1 ohm stable monoblock amp take 3 dual coil 6 Ohm subs and wire all six coils in parallell...
But one shouldn't wire stuff up just any wayimaginable - asymmetries in wiring scheme and or coil impedances will give diffent subs differing amounts of power.
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So that means that, since a high-rated speaker doesn't put any more strain on an amp than a low-rated one, and since a more-than-double-rated speaker should be able to handle the worst case from the amp, then the safest thing to do is get speakers that are rated more than two times the amps rating, yes? Ignoring playing sane volumes and economics.
Pretty much...There is a faction that claims the speaker (mainly subs) are cooled less well on a square wave than the same frequency sinewave because of the membrane 'standing still' for parts of the cycle, whiich woulld point to more than 2x. But as it [the mebane] still moves back and forth x times per second I'm sceptical, but have no proof either way.
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I'd say go with roughly the same ratings and be sensible with the gain setting, trust your ears.
So even with all this stuff that tells you that speakers can get damaged when they can't handle the power that the amp sends to them, you still run your fronts and subs with under-rated speakers. That tells me that setup and sanity are probably bigger factors than most of this anyway.
Not forgetting that the "marketing factor"  in both speaker and amp ratings can upset any calculated setup anyway...
As long as the gain setting is lower than the required setting for the rated power [given the input signal level from the HU], the max power delivered from the amp will be less than the rated power. If you set things up with 0dB on the empeg and adjust the gains to the lowest of a) no higher than it still all sounds clean or b) your ears cant take more.
I'd use an 'energetic' piece of music for this. Do one speaker set at a time. Then listen to them all together: a set to loud compared to the rest? Turn than gain knob down, don't turn the others up - just like with the equalizer, cut, don't boost... And if you after that never go over 0dB on the empeg your speakers should be quite safe.
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/Michael
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#259776 - 26/07/2005 00:38
Re: Speaker and Amp power ratings
[Re: wfaulk]
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carpal tunnel
Registered: 08/07/1999
Posts: 5549
Loc: Ajijic, Mexico
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So, what causes damage?
I was all set to jump in here with elaborate explanations... but Michael (mtempsch) did SO much better a job of it than I could ever do that I'll restrict myself to just one point that nobody brought up: one of the best ways to damage speakers is to feed them frequencies that they are not designed to handle. Hook your tweeters up to your subwoofer amplifier, cross it over at 80 Hz, and you'll see the smoke leak out of them in a hurry.
Other than that, just choose speakers that can handle the power required to play them at a listenable level -- and don't play them louder than that! -- and you'll be OK.
You could have a single 4" speaker connected to a 1,000 watt amplifier, and as long as you had the gain on that amplifier set to a level that wasn't too loud for the speaker, you would have no problems.
My system is nominally 1400 watts (five 2x100 class T amplifiers, with two of them running bridged mono) but I doubt if I have ever actually pulled more than 300 watts total out of it. None of the gains on the amplifiers are at more than half maximum, I'm running the input signals through potentiometers so I can tweak each amplifier individually and those pots are by default at half maximum volume, and I generally have the empeg running at -20 dB, with only three of the EQ channels at zero, the rest anywhere from two to 6 dB down. As Bitt suggested, that's head room.
With those settings my speakers are safe. But if I were to maximize the gains at every step along the way, I'm pretty sure I could catch all of them except for the subwoofers on fire.
tanstaafl.
tanstaafl.
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"There Ain't No Such Thing As A Free Lunch"
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#259777 - 02/11/2005 14:24
Re: Speaker and Amp power ratings
[Re: wfaulk]
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addict
Registered: 18/08/2002
Posts: 544
Loc: New Jersey
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more speakers are blown by overdriving an under-powered amp...i think Houdini said this
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...One man gathers what another man spills
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