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Post by urwi on Dec 13, 2016 14:58:52 GMT -5
I'm aware of this. The problem is that 99.9% of all consumers aren't aware of the fact. They don't understand phase. It is pretty easy to remove that 180° shift for them in the digital realm when they select 12dB slopes. Or at least you should add that information to the manual. urwi Bass management filters create a 180° phase shift when a 12dB filter slope is selected How is this a problem? You do realize that what is done in the digital realm has the same artifacts as if it was done in the analog realm. That is to say for every 6db of crossover slope, you get a 90 degree phase shift. So a 12db slope will always give you 180 degree phase shift, whether it is done in the digital or analog realm. BTW, this is true of all DSPs.  Just thought I would clarify that for you. Lonnie |
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Lonnie
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Post by Lonnie on Dec 13, 2016 15:12:25 GMT -5
I guess I'm missing your point.
it really doesn't matter what the phase is on the output because once you plug it into a Subwoofer all bets are off. What the electronics within the sub do as well as the placement in the room pretty much make what comes out of the processor irrelevant. Please also consider that you have to match the sub to the other speakers in the room which have crossovers that are shifting the phase as well and are not located on equal planes as the sub. Which is why they put phase controls on the subs and time delays in the processors.
But maybe i'm missing something here.
Lonnie
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Post by urwi on Dec 13, 2016 15:18:28 GMT -5
It's true that there's more energy in a square wave than in a sine wave. But the solution isn't "mo Watts" as the speaker will get fried anyway, either by the square wave of the small clipping amp or by the "clean" power delivered by the bigger amp. The solution is to get the right amount of Watts for a given speaker and SPL level. Back to MC-700. With the same speaker, in the same spot, in the same room, doubling the power will give you 3 dB more output, so 5 dB for three times the power sounds about right. (That's assuming that nothing clips, and nothing compresses or limits for any reason.) Your second paragraph is both right and wrong at the same time. Yes, tweeters usually get destroyed by overheated voice coils. HOWEVER, when you drive an amp into heavy clipping, because square waves have a very large proportion of higher-order harmonics, an abnormally high percentage of the amplifier's total power output ends up being sent to the tweeters, which makes it more likely that you will burn them out. So, if you have a powerful amplifier, and you simply turn it up too loud, you'll probably over-drive or overheat the woofers. And, if you have a somewhat smaller amp, and you drive it into excessive clipping in an attempt to make it player louder than it should, there's a very good chance that the excessive clipping will send too much power to your tweeters and cause them to overheat, and eventually burn them out. However, as urwi noticed.... this has a lot to do with speakers and nothing at all to do with the MC-700  Gary, I do NOT find it "unbelievable that 275 WPC could deliver 5 db more volume than 90 WPC". I just find it unbelievable that you and others make it sound like this will ALWAYS be the case - "mo is mo better", stated as a fact. That's simply not true and other factors are as important as having the RIGHT amount of power otherwise you're paying for Watts you don't need. My point was that manufacturers don't give you the necessary information to make an informed decision. The data Emotiva or even Monoprice provides is just a single part of the puzzle. You would also need to know distortion data and compression limits of your speakers besides required sound pressure level. This data isn't available to the customer. Not from Emotiva not from any other manufacturer. You can get such data sometimes in the pro market though. Speakers getting destroyed by weak amps clipping is a myth. Speakers either get destroyed by overexcursion (woofers) or by burned up voice coils (tweeters). Both the result of too much power when trying to drive a speaker beyond its mechanical or electrical limits. If there's interest in continuing this discussion I would like to ask you and others to open a new thread as this one is about the MC-700. |
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Post by urwi on Dec 13, 2016 15:30:21 GMT -5
Now I might be missing something here. Of course you have to set delay and level before optimizing the crossover region to the sub. What we hear at low frequencies is largely the room response. But there's still a fixed phase relationship between the subwoofer signal and the signal from the mains. So in no way is "what comes out of the processor irrelevant". Your experience with Dirac Live calibrated configurations should have shown you that at the crossover frequency there's a near perfect cancellation when applying a 180 degree out of phase 12dB filter via bass management. I guess I'm missing your point. it really doesn't matter what the phase is on the output because once you plug it into a Subwoofer all bets are off. What the electronics within the sub do as well as the placement in the room pretty much make what comes out of the processor irrelevant. Please also consider that you have to match the sub to the other speakers in the room which have crossovers that are shifting the phase as well and are not located on equal planes as the sub. Which is why they put phase controls on the subs and time delays in the processors. But maybe i'm missing something here. Lonnie |
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cawgijoe
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Post by cawgijoe on Dec 13, 2016 15:47:25 GMT -5
In thirty five years or so of amps and receivers, I have never had a problem with blown speakers. I never listen at ear splitting levels.
Having said that, I have noticed a much cleaner, fuller, with less effort sound from using more powerful amps. Pairing my Thiel CS1.6 (min. 4ohm) with a Denon receiver worked, but the sound was thin and the receiver
got quite warm. My XPA-5 works great with the speakers and remains cool.
Ok....back to the MC-700.
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Lonnie
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Post by Lonnie on Dec 13, 2016 16:27:13 GMT -5
Now I might be missing something here. Of course you have to set delay and level before optimizing the crossover region to the sub. What we hear at low frequencies is largely the room response. But there's still a fixed phase relationship between the subwoofer signal and the signal from the mains. So in no way is "what comes out of the processor irrelevant". Your experience with Dirac Live calibrated configurations should have shown you that at the crossover frequency there's a near perfect cancellation when applying a 180 degree out of phase 12dB filter via bass management. I guess I'm missing your point. it really doesn't matter what the phase is on the output because once you plug it into a Subwoofer all bets are off. What the electronics within the sub do as well as the placement in the room pretty much make what comes out of the processor irrelevant. Please also consider that you have to match the sub to the other speakers in the room which have crossovers that are shifting the phase as well and are not located on equal planes as the sub. Which is why they put phase controls on the subs and time delays in the processors. But maybe i'm missing something here. Lonnie With all due respect, I disagree on pretty much ever level here. So rather than get into an argument, I guess the best thing here is simply to agree to dis-agree. Best regards, Lonnie |
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Post by yves on Dec 13, 2016 17:55:41 GMT -5
Speakers getting destroyed by weak amps clipping is a myth.  |
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Post by brutiarti on Dec 13, 2016 18:11:26 GMT -5
Speakers getting destroyed by weak amps clipping is a myth. A very irresponsible statement |
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Post by Jim on Dec 13, 2016 19:11:18 GMT -5
Urwi probably also thinks that water isn't wet....so.....
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Lonnie
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Post by Lonnie on Dec 13, 2016 19:12:45 GMT -5
Speakers getting destroyed by weak amps clipping is a myth. Speakers either get destroyed by overexcursion (woofers) or by burned up voice coils (tweeters). Both the result of too much power when trying to drive a speaker beyond its mechanical or electrical limits. I agree with the above statement, but I would like to add the following just for clarification. A distorted (or clipped) signal in and of itself will not harm a speaker as long as the over all output power from the amplifier is within the thermal limits of the driver. As far as the driver is concerned its just a signal. Now having said that, the reason people think clipping can burn up a speaker is because of the following. When an amplifier clips, the output signal will become some form of a square wave depending on how much the amplifier is being over driven. When this occurs, there are two things that happen. First, there are harmonics generated at 1 octave intervals from the fundamental clipped frequency. These harmonics equate to additional power output. So there is an over increase in the output power that the voice coil has to deal with. Add to that the other issue which is the square wave itself. A normal unclipped sine wave gives a voice col plenty of time to cool down and only at peak power for a very short amount of time. A square wave on the other hand holds the voice coil at peak level for a much longer length of time. So the bottom line is this. The distortion itself means nothing. It is the increased output power from the amp coupled with the reduced cooling time will cause the thermal rise time of the voice coil to go up exponentially and this is what will burn up your speakers. Bottom line, clipping is not what kills a speaker, but it is the carrier of what kills a speaker. Always better to have more power then less in my humble opinion. Lonnie |
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Post by mgbpuff on Dec 13, 2016 19:26:25 GMT -5
It is usually the tweeter that will fail when the amplifier goes into clipping. This is because the squared off wave form of a clipped signal has a spectrum of high frequency components, even if the fundamental waveform is a low frequency, that may overwhelm the thermal capacity of the tiny and more vulnerable tweeter. Also there is no way a clipped wave form delivers more power than the unclipped waveform. The area under the clipped waveform is less than the unclipped, therefore the V square / Z or the I square x Z integrated power will also be less. it's just more energy is directed toward the tweeter via the speakers crossover filter under clipping.
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Post by teaman on Dec 13, 2016 19:27:21 GMT -5
A very irresponsible statement I fried my speakers rated for 200 w rms with a 35 wpc receiver. Not a myth |
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Post by teaman on Dec 13, 2016 19:30:02 GMT -5
I am starting to think urwi is only here for entertainment. No matter how minuscule in variation it is when somebody replies, urwi goes in for the attack....hahaha
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klinemj
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Post by klinemj on Dec 13, 2016 19:31:17 GMT -5
Now having said that, the reason people think clipping can burn up a speaker is because of the following. When an amplifier clips, the output signal will become some form of a square wave depending on how much the amplifier is being over driven. When this occurs, there are two things that happen. First, there are harmonics generated at 1 octave intervals from the fundamental clipped frequency. These harmonics equate to additional power output. So there is an over increase in the output power that the voice coil has to deal with. Add to that the other issue which is the square wave itself. A normal unclipped sine wave gives a voice col plenty of time to cool down and only at peak power for a very short amount of time. A square wave on the other hand holds the voice coil at peak level for a much longer length of time. So the bottom line is this. The distortion itself means nothing. It is the increased output power from the amp coupled with the reduced cooling time will cause the thermal rise time of the voice coil to go up exponentially and this is what will burn up your speakers. Sadly, I have direct experience on this from a friend who subjected my gear to this more than once. He seemed to like to experiment with how loud a system could play while using mine while I was not present. At least twice, I came into a room where my system was and he'd been at the helm, and the volume was through the roof. And, a tweeter was no longer playing but he kept thrashing my gear. What's worse? He knew better. Mark |
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Post by brutiarti on Dec 13, 2016 19:35:44 GMT -5
The buyer of my Dali Helicons fried the ribbon tweeters using a low power integrated amp, the damaged? almost $800 to replace them.
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Post by Dan Laufman on Dec 13, 2016 20:13:16 GMT -5
It is usually the tweeter that will fail when the amplifier goes into clipping. This is because the squared off wave form of a clipped signal has a spectrum of high frequency components, even if the fundamental waveform is a low frequency, that may overwhelm the thermal capacity of the tiny and more vulnerable tweeter. Also there is no way a clipped wave form delivers more power than the unclipped waveform. The area under the clipped waveform is less than the unclipped, therefore the V square / Z or the I square x Z integrated power will also be less. it's just more energy is directed toward the tweeter via the speakers crossover filter under clipping. You win the test! This is exactly the mechanism that causes small amplifiers, when driven into clipping to destroy tweeters. Quickly! Urwi knows just enough to be dangerous. As a client Urwi, I respect you and appreciate your involvement. However do not pass yourself off as an expert. Your knowledge has too many holes in it. Many of your claims here are easily refuted. If you care to open your mind you can learn a lot from the people here. Now, back to the game! |
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Post by novisnick on Dec 13, 2016 20:28:42 GMT -5
Now having said that, the reason people think clipping can burn up a speaker is because of the following. When an amplifier clips, the output signal will become some form of a square wave depending on how much the amplifier is being over driven. When this occurs, there are two things that happen. First, there are harmonics generated at 1 octave intervals from the fundamental clipped frequency. These harmonics equate to additional power output. So there is an over increase in the output power that the voice coil has to deal with. Add to that the other issue which is the square wave itself. A normal unclipped sine wave gives a voice col plenty of time to cool down and only at peak power for a very short amount of time. A square wave on the other hand holds the voice coil at peak level for a much longer length of time. So the bottom line is this. The distortion itself means nothing. It is the increased output power from the amp coupled with the reduced cooling time will cause the thermal rise time of the voice coil to go up exponentially and this is what will burn up your speakers. Sadly, I have direct experience on this from a friend who subjected my gear to this more than once. He seemed to like to experiment with how loud a system could play while using mine while I was not present. At least twice, I came into a room where my system was and he'd been at the helm, and the volume was through the roof. And, a tweeter was no longer playing but he kept thrashing my gear. What's worse? He knew better. Mark A "friend" would respect YOU and your gear. Im sorry to inform you, that person is NOT a friend.  |
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Post by audiobill on Dec 13, 2016 20:40:09 GMT -5
What fries speakers in the end is listening too loud, which also fries ears. Then the "listener" turns it up more.
It's a mystery to me how killing your sensitive hearing qualifies one as an audiophile, "THX Standard" be damned.
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Post by monkumonku on Dec 13, 2016 21:04:13 GMT -5
Sadly, I have direct experience on this from a friend who subjected my gear to this more than once. He seemed to like to experiment with how loud a system could play while using mine while I was not present. At least twice, I came into a room where my system was and he'd been at the helm, and the volume was through the roof. And, a tweeter was no longer playing but he kept thrashing my gear. What's worse? He knew better. Mark A "friend" would respect YOU and your gear. Im sorry to inform you, that person is NOT a friend. No lie.. what kind of "friend" is that??? |
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klinemj
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Post by klinemj on Dec 13, 2016 21:05:55 GMT -5
A "friend" would respect YOU and your gear. Im sorry to inform you, that person is NOT a friend. Sadly, I did discover that on many levels. I no longer call him a friend, and it goes far beyond blowing my speakers. Mark |
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urwi
