XPRs not doubling power at 4 Ohms.

[jackfish]

When the XPR amps were in their formative stage the discussions were about them doubling their 8 Ohm power rating into 4 Ohms. Early releases of specs had the amps achieving this, while subsequent iterations of the power ratings incrementally moved away from it. I'm wondering if this is just a matter of how they wanted to state the final power ratings in regards to watts, frequency response and THD.

[DYohn]

It likely means the power supply is regulated (or the output is) to keep the line load low enough to plug it into a wall outlet.

[Dan Laufman]

Hi,
The amplifiers will easily double their rated 8 ohm power. However in order to meet our stringent THD requirements, we have backed off the rated power level slightly in order to show you very conservative, low distortion four ohm specifications.

Believe me, they can easily exceed their published spec. We want to make sure that we do not overstate our specs. or push the measurement envelope in any manner.

As a side note, just read a glowing review of a $2,200.00 "super receiver" in a well known magazine. The reviewer praised the unit which is rated at 7x150 watts into 8 ohms for being able to deliver a blistering 7x63 watts at 8 ohms with all channels driven!! Wow!! Hold me, I think I'm going to faint!! Geez.

Can you imagine what power levels we could state if we measured them like a receiver?? Ha!!

We welcome comparison with any other product out there.

Cheers,
Big Dan

[SticknStones]

Dec 28, 2012 19:05:48 GMT -5 Dan Laufman said:

Hi,
The amplifiers will easily double their rated 8 ohm power. However in order to meet our stringent THD requirements, we have backed off the rated power level slightly in order to show you very conservative, low distortion four ohm specifications.

Believe me, they can easily exceed their published spec. We want to make sure that we do not overstate our specs. or push the measurement envelope in any manner.

As a side note, just read a glowing review of a $2,200.00 "super receiver" in a well known magazine. The reviewer praised the unit which is rated at 7x150 watts into 8 ohms for being able to deliver a blistering 7x63 watts at 8 ohms with all channels driven!! Wow!! Hold me, I think I'm going to faint!! Geez.

Can you imagine what power levels we could state if we measured them like a receiver?? Ha!!

We welcome comparison with any other product out there.

Cheers,
Big Dan

Ain't it Cool!

[audiofile]

That reviewer must be paid, in part or otherwise compensated, by the receiver manufacturer. They are all aglow when they are enriched by singing the praises of whomever pays the bills.

[jevans64]

Not a problem for me as I really only look at the 8 Ohm load specs anyway. Anything beyond that is just gravy for me.

The receiver manufacturers are getting to be down-right deceitful these days. I've even seen power ratings from some of them with a 10% THD. LOL Most rate theirs at 0.1 to 1% THD with one or two channels driven. The drop is usually 50% for 5 channels and 60% for 7 channels. The most important thing on an AVR for me would be processing power and features... and pre-outs so I can add external amplification.

My 5-year-old Denon AVR is actually pretty close to its 2-channel rated power driving 7 channels. Only an 8 watt difference between 2 channels and 7 channels.

[ÈlTwo]

That's why I always loved my old HK 7200, it actually exceeded its rated specs with all 5 channels driven. I believe Sound&Vision had it rated at 142 watts per channel at clipping, all 5 channels driven.

[knucklehead]

I bought an HK AVR 525 10 or 12 years ago that was rated at 65wpc all 5 channels driven. I remember the first time I plugged my pair of Infinity IL40s into it with no other speakers connected. I think it was as much stereo power I'd had up to that point. It probably put out 100 or more wpc in stereo. Now that I don't listen so loudly I have more power than ever before and not nearly as much use for it.

Some amp manufacturers use an old trick to double the power from 8 down to 4 ohms. They just under rate the 8 ohm spec. Actual power output might be 225/400wpc but they spec it to 200/400wpc.

[LCSeminole]

Whether or not my XPR-5 will actually double it's power at 4ohms has never been an issue with me as I've always known Dan and Lonnie to take the conservative ratings approach. Besides, I moved away from receivers a while ago so I would never have to be concerned about any clipping issues.

[edoggrc51]

Dec 29, 2012 9:26:34 GMT -5 LCSeminole said:

I would never have to be concerned about any clipping issues.

Then you're not listening loud enough! ;D

I managed to clip the XPR once while watching a scene from The Dark Knight Rises.

[kt10r]

What did the clipping sound like?

[audiofile]

Dec 29, 2012 9:26:34 GMT -5 LCSeminole said:

Whether or not my XPR-5 will actually double it's power at 4ohms has never been an issue with me as I've always known Dan and Lonnie to take the conservative ratings approach. Besides, I moved away from receivers a while ago so I would never have to be concerned about any clipping issues.

I made the same move when I realized how futile it was to try and drive the Vienna's with my Denon AVR! I have never second guessed their performance and the ability of my XPA-1's to power those speakers.

[RightinLA]

Does one really need more than 300 watts of power for a home speaker in even a modestly large home room anyways?
To me the question is moot.
I see this more as bragging rights than real practicality.

[monkumonku]

Dec 29, 2012 13:34:06 GMT -5 RightinLA said:

Does one really need more than 300 watts of power for a home speaker in even a modestly large home room anyways?
To me the question is moot.
I see this more as bragging rights than real practicality.

Oh you're just sour grapes. ;D

That said, yeah, I know I don't use anywhere near the capacity of my amps but I just like having them. Many of the power LED's will never know what it is like to be lit up.

[sharkman]

Dec 29, 2012 9:26:34 GMT -5 LCSeminole said:

Whether or not my XPR-5 will actually double it's power at 4ohms has never been an issue with me as I've always known Dan and Lonnie to take the conservative ratings approach. Besides, I moved away from receivers a while ago so I would never have to be concerned about any clipping issues.

Several days ago I bemoaned the fact that the XPR amps are not 2 ohm stable. In short order Lonnie himself came on the thread to insist that these amps are indeed 2 ohm stable, they just didn't want to make it common knowledge since people would perhaps overdo it in some way. Then the very next post was asking if the XPR-2 could do 2 ohms while bridged, proving Lonnie's point.

Now I see someone bemoaning that the amps can't double their power at 4 ohms, and Dan himself comes on the thread to insist that these amps can indeed double their power at 4 ohms, but they wanted to give very conservative numbers only.

I really do not understand this marketing approach. If the amps are 2 ohm stable and can double their power at 4 ohms, then it should be stated in the specs, let the chips fall where they may. So what if they outperform other brands?

[audiofile]

Dec 29, 2012 13:34:06 GMT -5 RightinLA said:

Does one really need more than 300 watts of power for a home speaker in even a modestly large home room anyways?
To me the question is moot.
I see this more as bragging rights than real practicality.

Heresy!!!

I know I have more power than I need for normal listening and even for those higher decibel listening sessions. However, I also never have to worry about a overworked amplifier nor a clipped speaker when I enter the wall flexing listening mode my wife hates some much. ;D

Who knows...I may need that power in the future should I go totally around the bend and replace the Vienna speakers with something a bit more power hungry.

[Jim]

Dec 29, 2012 13:45:47 GMT -5 sharkman said:

Dec 29, 2012 9:26:34 GMT -5 LCSeminole said:

Whether or not my XPR-5 will actually double it's power at 4ohms has never been an issue with me as I've always known Dan and Lonnie to take the conservative ratings approach. Besides, I moved away from receivers a while ago so I would never have to be concerned about any clipping issues.

Several days ago I bemoaned the fact that the XPR amps are not 2 ohm stable. In short order Lonnie himself came on the thread to insist that these amps are indeed 2 ohm stable, they just didn't want to make it common knowledge since people would perhaps overdo it in some way. Then the very next post was asking if the XPR-2 could do 2 ohms while bridged, proving Lonnie's point.

Now I see someone bemoaning that the amps can't double their power at 4 ohms, and Dan himself comes on the thread to insist that these amps can indeed double their power at 4 ohms, but they wanted to give very conservative numbers only.

I really do not understand this marketing approach. If the amps are 2 ohm stable and can double their power at 4 ohms, then it should be stated in the specs, let the chips fall where they may. So what if they outperform other brands?

While the fact that they're 2 ohm stable implies a real technical capability, who owns a 2 ohm speaker? Or should? (A 2 ohm speaker is just silly). Stating it as a real capability does run the risk of it getting abused (and you know people would ) .

If Emotiva published wattaged specs with higher distortion than they have in the past it would throw throw the high standard out the window. If anyone tested it, they'd say "Oh my gosh this amp has higher distortion at wattage XYZ, what were they thinking?!" Sure, all Emotiva amps can put out higher wattages than the spec, but they won't meet the listed distortion specs.

Dan's statement "Believe me, they can easily exceed their published spec. We want to make sure that we do not overstate our specs. or push the measurement envelope in any manner. " embodies why I like Emotiva's philosophy and amps as much as I do! Lonnie and Dan taking the time to comment about the capabilities speaks volumes about the amps as well.

[edoggrc51]

Dec 29, 2012 13:11:15 GMT -5 kt10r said:

What did the clipping sound like?

POP POP POP

The clip indicator also light up on the left main channel.

Dec 29, 2012 13:34:06 GMT -5 RightinLA said:

Does one really need more than 300 watts of power for a home speaker in even a modestly large home room anyways?
To me the question is moot.
I see this more as bragging rights than real practicality.

If you're speakers are demanding enough and your listening levels are high enough (for me its usually between -5db's & -10db's from reference), then sure you do.

Dec 29, 2012 13:41:59 GMT -5 monkumonku said:

Many of the power LED's will never know what it is like to be lit up.

Mine light up all the time! ;D

[RightinLA]

Dec 29, 2012 13:41:59 GMT -5 monkumonku said:

Dec 29, 2012 13:34:06 GMT -5 RightinLA said:

Does one really need more than 300 watts of power for a home speaker in even a modestly large home room anyways?
To me the question is moot.
I see this more as bragging rights than real practicality.

Oh you're just sour grapes. ;D

That said, yeah, I know I don't use anywhere near the capacity of my amps but I just like having them. Many of the power LED's will never know what it is like to be lit up.

How can it be sour grapes when I own a pair of XPA-1's?

If all the power LED's lit up I doubt that I would be close enough to see it.

[sharkman]

Dec 29, 2012 14:07:35 GMT -5 Jim said:

While the fact that they're 2 ohm stable implies a real technical capability, who owns a 2 ohm speaker? Or should? (A 2 ohm speaker is just silly). Stating it as a real capability does run the risk of it getting abused (and you know people would ) .

If Emotiva published wattaged specs with higher distortion than they have in the past it would throw throw the high standard out the window. If anyone tested it, they'd say "Oh my gosh this amp has higher distortion at wattage XYZ, what were they thinking?!" Sure, all Emotiva amps can put out higher wattages than the spec, but they won't meet the listed distortion specs.

Dan's statement "Believe me, they can easily exceed their published spec. We want to make sure that we do not overstate our specs. or push the measurement envelope in any manner. " embodies why I like Emotiva's philosophy and amps as much as I do! Lonnie and Dan taking the time to comment about the capabilities speaks volumes about the amps as well.

Thanks once again Jim, you defend Emotiva so well!

On the 2 ohm speaker though, I am puzzled you would jump to that conclusion, it has nothing to do with a 2 ohm speaker. The XPR amps have a listed recommendation for minimum load on each channel, and it's 4 ohm. Since these amps can do 2 ohm, it seems odd to me that they don't advertise this, even after what you have said on the matter.

As for the wattage specs, the XPA series are published at .1% THD, while other brands publish at under.01, so their numbers do seem high rather than low to begin with. Don't get me wrong here, they have great bang for buck. It does appear here that the XPR amps hit their 4 ohm rated power while at a lower THD which is again better than the XPA series. But if they can double their power at 4 ohms but are maybe up to 1% THD while doing it, I can see Dan's point. Either way, they don't have to apologize, the XPR amps are indeed a new bench mark. I'd never have need of one, but many are reporting they are amazing.