Emotiva XPR-1 1kwatt Mono Amplifier Review

[Goliath]

It's generally well understood that underpowering speakers burns them out.

You have it backwards - applying to much continuous power can burn speakers out, or burn the voice-coils. Applying too little power will never cause thermal damage. If that was the case then every time you turned the volume down it would burn speakers out.

 

[Irvrobinson]

You have it backwards - applying to much continuous power can burn speakers out, or burn the voice-coils. Applying too little power will never cause thermal damage. If that was the case then every time you turned the volume down it would burn speakers out.

I think he's referring to amplifier clipping, which can indeed harm drivers.

 

[Goliath]

I think he's referring to amplifier clipping, which can indeed harm drivers.

Which is yet another myth. Clipping by itself can't harm drivers. Guitar amps generate lots and lots of gross audible distortion from clipping, but speakers survive it just fine. Clipping can be harmful if the additional power exceeds the thermal rating of the speaker. Since that is what causes speaker damage - not gross distortion. You could theoretically run an amplifier into gross distortion all day long and still never exceed the thermal power handling limits.

 

[haraldo]

some of you guys do not have an upcoming career-path as diplomats

 

[Irvrobinson]

Which is yet another myth. Clipping by itself can't harm drivers. Guitar amps generate lots and lots of gross audible distortion from clipping, but speakers survive it just fine. Clipping can be harmful if the additional power exceeds the thermal rating of the speaker. Since that is what causes speaker damage - not gross distortion. You could theoretically run an amplifier into gross distortion all day long and still never exceed the thermal power handling limits.

I've never seen a guitar amp that wasn't AC-coupled. Clipping a DC-coupled audiophile amp can be more problematic. Not always, but there are many amplifier designs out there, and not all of them are especially good ones.

 

[Goliath]

I've never seen a guitar amp that wasn't AC-coupled. Clipping a DC-coupled audiophile amp can be more problematic. Not always, but there are many amplifier designs out there, and not all of them are especially good ones.

If clipping an amplifier does not result in enough distorted power to damage the speaker then no amount of clipping will damage the speaker. I've clipped a few low-powered amplifiers with my speakers into gross distortion and they survived the onslaught just fine.

If the average power increased sufficiently to exceed the thermal rating of the speaker for long enough then that's a different story. Simply clipping an amplifier is no guarantee of that actually happening. I just wanted to comment on the "clipping damages speakers" point because people often repeat this myth as if it were true. It's not the clipping that does the damage, it's the power. Too much power, to be precise. Since clipping results in more distorted power to the speaker that is no guarantee that it would exceed the thermal limits of that speaker!

The "nice" thing about underpowered amplifiers driven into gross distortion via clipping is that it allows the user necessary time to turn the volume down, since that is what normal people would do if their speakers were distorting. Of course, this is not the case with overpowered amplifiers where the power is so clean the user would not be given the same warning signs, so they just turn the volume up and up until poof! Permanent speaker damage.

 

[PENG]

It's generally well understood that underpowering speakers burns them out.

From what I read on forums (assuming that's where you've got your impression from too), the opposite is true. I would say it is generally well MISunderstood on that count. Problem is someone make a generic statement like this, and then the hearsay process starts and never seem to end.

If you limit the volume to what sounds good, you will not over power your speakers.

That, I can agree to.

I'm runing the XPA-1s wiht my KEF 205/2 which has a recommended power range of 50-300 and I peak at 500W on the meters (which are slow, I believe) and so peaks could be approaching 1000 on very short bursts.

Well that's amazing, or unbelievable I should say. I spent quite some time once listening to the Blades powered by two 1kW monoblock McIntosh amps with gigantic analog meters that can capture fast peaks nicely. Listening to near unbearable SPL, and with various music including some with very heavy bass material and high dynamic range. Most of the time the meter pointed to between 0.1 to 12W, up to around 200W very occasionally. I was only able to capture at the 120W mark a couple of times no matter how hard I tried and until my arms were tied holding the camera and waiting for those moments. If your meter did register 500W, and if the meter is of the analog type, there is no way you were getting 1000W on short burst. It does not make sense that going from 500W to 1000W of power reserve when only a fraction of that are used most of the time except for your so called short burst, will yield another "layer" of sound/details, not even for golden ears.

These short bursts do not represent much "Power" so no worries.

That is incorrect, power is power, regardless of how short the burst it is. You would be correct if meant such short "power" burst do not represent much "Energy", because energy proportional to power and time (duration).

 

[PENG]

I've never seen a guitar amp that wasn't AC-coupled. Clipping a DC-coupled audiophile amp can be more problematic. Not always, but there are many amplifier designs out there, and not all of them are especially good ones.

Those millions of Ghetto blasters in workshops, garage and canteens are another example, people often leave them on full blast to the point anyone can tell they were clipping, yet their built in speakers last forever, at least seem that way. Of course, they don't have tweeters in them that could be much more prone to damage by the badly clipped signal. Overall I do agree this underpower is what caused speakers or even tweeters are blown way out of proportion via repeated hearsays, though I probably wouldn't call it a myth as such.

 

[Irvrobinson]

If clipping an amplifier does not result in enough distorted power to damage the speaker then no amount of clipping will damage the speaker. I've clipped a few low-powered amplifiers with my speakers into gross distortion and they survived the onslaught just fine.

If the average power increased sufficiently to exceed the thermal rating of the speaker for long enough then that's a different story. Simply clipping an amplifier is no guarantee of that actually happening. I just wanted to comment on the "clipping damages speakers" point because people often repeat this myth as if it were true. It's not the clipping that does the damage, it's the power. Too much power, to be precise. Since clipping results in more distorted power to the speaker that is no guarantee that it would exceed the thermal limits of that speaker!

The "nice" thing about underpowered amplifiers driven into gross distortion via clipping is that it allows the user necessary time to turn the volume down, since that is what normal people would do if their speakers were distorting. Of course, this is not the case with overpowered amplifiers where the power is so clean the user would not be given the same warning signs, so they just turn the volume up and up until poof! Permanent speaker damage.

I see. I thought I recognized some of your answers, and now I remembered where I've seen your arguments before, on a car audio web site. Especially that comment about how if low-power amps hurts speakers, then you'd blow a speaker every time you turned down the volume control. That's nearly a direct quote, and it's a non-sequitur. Are you the original author, or just a copycat?

 

[Irvrobinson]

Those millions of Ghetto blasters in workshops, garage and canteens are another example, people often leave them on full blast to the point anyone can tell they were clipping, yet their built in speakers last forever, at least seem that way. Of course, they don't have tweeters in them that could be much more prone to damage by the dc components in the badly clipped signal. Overall I do agree this underpower is what caused speakers or even tweeters are blown way out of proportion via repeated hearsays, though I probably wouldn't call it a myth as such.

Some tweeters are rather intolerant of abuse, and some solid state amps aren't very linear when clipped. Guitar amp/speaker combos and boom boxes are almost certainly tested during development to tolerate clipping, but a lot of home speakers aren't, and I've seen more than one with some pretty weak-looking crossover components. My friend with B&W 802Ds tells me that blowing tweeters is the bane of the B&W user base, and that dealers tell them it is due to clipping amps. I'm less convinced, but a quick Google search some time ago did point to several discussions about it. Whatever. To be honest, I'm probably guilty of arguing a difficult to defend position just to be difficult. (No surprise, eh?)

 

[Grador]

Some tweeters are rather intolerant of abuse, and some solid state amps aren't very linear when clipped. Guitar amp/speaker combos and boom boxes are almost certainly tested during development to tolerate clipping, but a lot of home speakers aren't, and I've seen more than one with some pretty weak-looking crossover components. My friend with B&W 802Ds tells me that blowing tweeters is the bane of the B&W user bass, and that dealers tell them it is due to clipping amps. I'm less convinced, but a quick Google search some time ago did point to several discussions about it. Whatever. To be honest, I'm probably guilty of arguing a difficult to defend position just to be difficult. (No surprise, eh?)

Those systems are tolerant to clipping because they're designed to handle the amount of power that is provided by the amp under clipping conditions.

I really don't understand your disagreement with his point. What's the alternative method of damage by clipping you're proposing other than power?

 

[PENG]

(No surprise, eh?)

Nope, right on. Seriously, I did hear about the 802D (the original diamond) tweeter being intolerant, from at least one dealer. Apparently they fixed that on the 802 Diamond (or D2 I guess). So I won't argue with you on this one, and I am sure the 802D won't be alone on this.

 

[Irvrobinson]

I really don't understand your disagreement with his point. What's the alternative method of damage by clipping you're proposing other than power?

So-called "soft-clipping" circuits. Basically, these circuits keep the amplifier well-behaved even when they're over-driven.

 

[Grador]

So-called "soft-clipping" circuits. Basically, these circuits keep the amplifier well-behaved even when they're over-driven.

I highly doubt boomboxes have soft clipping circuits, but that doesn't answer the real question. If it's not clipping related excess power draw, what about clipping is causing the damage?

 

[Irvrobinson]

I highly doubt boomboxes have soft clipping circuits, but that doesn't answer the real question. If it's not clipping related excess power draw, what about clipping is causing the damage?

Oh, all right, we'll discuss it. I was trying to scurry away. Boom boxes probably don't have soft-clipping circuits, but they don't have typically have tweeters and crossovers either. The point was that guitar amps and boom boxes are poor examples of why clipping doesn't matter.

Amplifier clipping is not a simple subject to discuss. For example, clipping can be caused by input stage overload, and then the distortion will have a different characteristic than if the output stage is just running out of current. Clipping adds frequencies to the signal, and can add more amplitude, that weren't in the original signal, and what those additions look like vary between designs. For some direct-coupled amps there's additional DC. Certainly there's more output higher up in the frequency spectrum than there would be in an undistorted signal - but it's not correct to make any blanket statements. Some amps don't clip, they can't, because they have limiters that prevent it. Some speakers, crossovers, and drivers, are more sensitive to clipping abuse than others, and since amps vary and speakers vary making any sort of blanket statement strikes me as reaching for generalizations, which may not be the case.

Frankly, I'm sorry I made the statement in the first place. Anyone who wants to clip their amps and see what happens is more than welcome to. It may well be that no damage occurs, but I wouldn't do it.

 

[Grador]

Obviously you're correct clipping is a circumstance that can cause damage.

My point was simply that his point didn't seem to be that "clipping" isn't an issue. The clipping itself isn't what destroys the drivers, it's the power that is derived from the clipping.

Edit:

Which is yet another myth... Clipping can be harmful if the additional power exceeds the thermal rating of the speaker

This really isn't a blanket statement, it's pretty well qualified.

 

[Goliath]

I see. I thought I recognized some of your answers, and now I remembered where I've seen your arguments before, on a car audio web site. Especially that comment about how if low-power amps hurts speakers, then you'd blow a speaker every time you turned down the volume control. That's nearly a direct quote, and it's a non-sequitur. Are you the original author, or just a copycat?

It's a comment I've heard before online and thought it would be relevant to the other posters. It's not a direct quote, I never copied and pasted anything, but I do remember something similar being posted years back.

Your point? Do you have an actual argument here to address my other points, or are you going to grill me over some comment that I heard in a message board several years ago?

Stick to the topic please.

 

[Goliath]

[QUOTE="Irrobinson]Some speakers, crossovers, and drivers, are more sensitive to clipping abuse than others, and since amps vary and speakers vary making any sort of blanket statement strikes me as reaching for generalizations, which may not be the case.[/quote]

What generalisations have been made exactly?

Frankly, I'm sorry I made the statement in the first place. Anyone who wants to clip their amps and see what happens is more than welcome to. It may well be that no damage occurs, but I wouldn't do it.

Been there and done that. Amplifier clipping is not the death sentence that people make it out to be. However it's not something I recommend people go and do for fun.

 

[Goliath]

[QUOTE="Irvrobinson]The point was that guitar amps and boom boxes are poor examples of why clipping doesn't matter.[/QUOTE]

Why are guitar amps bad examples?

 

[Irvrobinson]

Why are guitar amps bad examples?

There are several reasons. The first is that guitar speakers normally use only relatively large drivers with a limited bandpass. These types of drivers are the least likely to get damaged by an amplifier's clipping behavior. Second, distortion is part of the amp-speaker design center for electric guitars, that is to say distortion is a component of the target music, and therefore for the speakers they use. Guitar players often use special effects equipment that specifically includes injected distortion, like a Stompbox, so manufacturers naturally make sure distortion doesn't hurt anything. Finally, and perhaps it is just that I hang around old guitar players, but all of the guitar amps I see use tubes, and tubes don't exhibit the same clipping nonlinearities that solid state amps do.