EMOTIVA Amps - Power Rating Discussion - AVS Forum
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post #1 of 421 Old 02-16-2011, 08:19 AM - Thread Starter
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This THREAD is to discuss everyones knowledge of the Power Rating of the EMOTIVA Amplifiers, and comparisons to other Amplifiers as well.

There are a lot of factors that contribute to how one Mfg. rates output power vs. another Mfg. -- and it seems NO ONE uses the same tests exactly.

Therefore, it makes it almost impossible to compare one amp. to another, making it difficult at best for us the Buyers to make an intelligent decision regarding what amp to purchase.
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post #2 of 421 Old 02-16-2011, 08:34 AM - Thread Starter
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How can the XPA-5 produce 200W RMS / Channel with all five channels driven, when it is a Class A/B amp design?

Was their tests done w/ a Variac to hold up the 120Vac input to the amp?

Was it a Continuous Test and if so, for how long?

What type of input signal to amp, like Sinusoidal Waveform at 1KHz. or a full frequency Sweep Test, or ?

There is a great article by Gene DellaSala at URL:

http://www.audioholics.com/education...amplifier-test

Does anyone have ANY REAL TRUE LIFE BENCH TESTING data of the EMO amps and the specifics of how the tests were performed?
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post #3 of 421 Old 02-16-2011, 08:52 AM
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Have you searched around at all? Pretty easy to find some stuff. Here is one third party review with bench tests.

http://www.audioholics.com/reviews/a.../emotiva-xpa-2

Or you could call Emotiva directly and talk to them.
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post #4 of 421 Old 02-16-2011, 09:08 AM
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^^
I completely believe the power ratings for the XPA2 & XPA1. However, I'm skeptical the XPA5 can output the same power all CH driven using the SAME identical power supply.

I also would like to see a real bench test on the XPA5. Other than the usual subjective BS, all I can find is bench tests on XPA1 and XPA2. Believe me, I've been looking for the past yr or more

I even asked an Emotiva representative at Sept's CEDIA booth and couldn't get a straight answer. I find it hard to believe their XPA5 can deliver the same power output all channels driven across the full freq band as Parasound's A51 with a power supply about half the size as the A51, even considering that the A51 is initially biased to class A. Or even the Anthem A5 for that matter. Physics is physics.

Please, I'm sincerely looking for proof, some objective review with test measurements, because if the XPA5 can do this, it would definitely be on my list for an ext amp.

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post #5 of 421 Old 02-16-2011, 09:18 AM
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I understand your concern, but every one of there amps that has been bench tested has at least very easily met the advertised specs. I find no real reason that any of the XPA amps would not meet there specs. They have a money back guarantee, why not give them a shot? BTW, I have an XPA-3 and love it. Good luck. Even the UPA amps very easily meet there specs.

http://www.audioholics.com/reviews/a...7-measurements
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post #6 of 421 Old 02-16-2011, 09:39 AM
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Too bad their UPA-7 is being discontinued. Crazy thing is it is getting all these great reviews. According to their podcast, it doesn't sell well enough to justify it taking up space in their warehouse. Whereas HT installers buy the 7 channel amps, enthusiasts tend to go for the XPA-5/2 combo to meet their 7 channel needs.
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post #7 of 421 Old 02-16-2011, 10:37 AM
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This is what I think...

Their measurement was not for a long duration. The FTC used to call for 5 mins for the RMS measurement. To the best of my knowledge, Emotiva ignored this when talking about all channels driven (but they easily meet the two channel test I am sure, which is all that is really required to meet FTC rules.)

Based on what I have read, Emotiva tested their amps with a sweep. In other words, they ran the power from 0 to the stated THD with all channels driven over a short time. Also, they may have used a 1 khz test tone only (I believe they even stated this directly in some thread.)

Note that the power transformer rating is not a max rating, it's a power handling rating as far as I know. Which means the transformer may be able to do better than it's VA rating.

Also, it has reservoir caps in the power supply, quite a bit of capacitance. This helps it hold voltage to the output transistors as long as the charge is sufficient. In fact the power supply voltage is almost certainly quite a bit higher than is needed to do 200 watts RMS (40 volts RMS according to my calcs, is all that would be needed, or 57 V peak.) With my limited knowledge of electronics, it sure seems like they could provide very good dynamic headroom. I think it would come down to their limiter circuits and thermal circuits - if those were not in place, who knows what sort of power it could output before it blew up.

I don't think they are all that misleading. They say all channels driven, and I think their published data is legit as long as you understand that it's probably not 20hz to 20khz over a 5 minute time period. It's a ton of power in any case, IMO.

One more thing - some say they are conservative. I have to call BS on that. Look at their graphs. They are clearly limiting/clipping at the point where they measure power. Not that I am saying you can hear .01%THD. But look at the graphs and then come back and try to convince me it's a conservative measurement.

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post #8 of 421 Old 02-16-2011, 10:45 AM - Thread Starter
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Quote:
Originally Posted by nixonrsx View Post

Have you searched around at all? Pretty easy to find some stuff. Here is one third party review with bench tests.

http://www.audioholics.com/reviews/a.../emotiva-xpa-2

Or you could call Emotiva directly and talk to them.

I have called Vincent Chen at Emotiva, and spoke with him. Vincent stated that he is not an Engr. so send your technical questions to Lonnie via Email, of which I have done. But no reply in a few days yet.

The XPA-5 is showing a Xformer Size = 1200 VA and many are questioning how EMO could get 200W RMS per Ch. with All Channels Driven (ACD) or 200 x 5 = 1000W, since this amp is a Class A/B design, and in practical design Modern Class AB amplifiers are commonly between 35–55% efficient with a theoretical maximum of 78.5%. (per WikiPedia).

I have yet to see or read a Bench Test on the XPA-5, excluding EMO's test data, using the Audio Precision Test Equipment, which I hear is some of the best in Audio for testing, but there are so many specifics that I do not see, such as:

1.) How long was this test performed for in Sec./Min./Hrs./Days or what?
2.) Was a Variac used to hold the input line voltage up to 120Vac to eliminate Line Sag during the test?
3.) Was the 8 Ohm test load a full Resitive or Reactive Load (R/L/C) more like a real speaker?
4.) At 120Vac RMS off of the wall, what magnitude of source current was measured at full power rating? Remembering that most ccts. in residences are 15 Amps max.

Now take our 1800 watt (120V x 15A) max power from the wall, and that would be assuming a PF - Power Factor = 1, which it is most definately is not, and multiply it by our amp efficiency (let's choose 45%) and we get: 1800 x .45 = 810 watts. This is the max power a typical linear A/B amp can deliver on a continuous basis from a 120V, 15A household line - assuming, of course, the amplifier's power supply can consume the entire 1800 watts of power from the line without causing the power transformer to overheat or go into thermal meltdown and likely trip the breaker.

So, maybe the EMO XPA-5 can produce 1000W, or approx. 24% more than 810W for a very short period of time, BUT NOT CONTINUOUSLY ... so it seems to me.

Also, looking at the XPA-1 (500W - 8 Ohms) and XPA-2 (2 x 300W - 8 Ohms), that I believe BOTH of these Amps WOULD BE ABLE to meet their spec. since 500W and 600W is a lot lower than the 810Watts as stated above, and that would allow for the Power Factor worse case even to drop down to 0.74 for the XPA-2, of which we know the PF will be alot higher in most cases (generally between 0.70 - 0.95), so we are on the lower end of the dimensionless value for PF.
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post #9 of 421 Old 02-16-2011, 10:53 AM
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Den, you are still assuming some stuff? (For example, that the VA rating of the transformer is the ultimate limit of power output, which I think is not quite right.) Please read my post, and then respond to that.

I have spent hours thinking about this and reading every post on it. I could be wrong, but I think I made some good points?

If you read all the threads on this topic everyone on the net, especially over at Emotiva lounge, and read between the lines, at no point is Emotiva making any claims about the duration (it was beaten to death over there.)

As long as they meet FTC rules for two channel power, they are not in violation of the FTC amp rule either, IMO.

I honestly think their numbers are legit, as long as the test conditions are understood (which admittedly, I don't think they have ever fully revealed.)

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post #10 of 421 Old 02-16-2011, 10:58 AM
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One more point...

If their dynamic power is as good as I think it is, it's hard to imagine not having enough power with their 200 watt / channel amps.

You would need inefficient speakers in a larger room running at reference level.

In my own system, I could NEVER get the clipping light of my Crown XLS 1000 to come on when playing at reference level. Admittedly it's running the rear surround speakers, which is arguably a less demanding application than the front speakers.

I could be wrong (as usual but I have long suspected people need less power than they think they need. Even when running at reference level, because those 105 dB peaks (115 dB LFE) are short term events.

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post #11 of 421 Old 02-16-2011, 11:07 AM
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Quote:
Originally Posted by MichaelJHuman View Post

One more point...

If their dynamic power is as good as I think it is, it's hard to imagine not having enough power with their 200 watt / channel amps.

You would need inefficient speakers in a larger room running at reference level.

In my own system, I could NEVER get the clipping light of my Crown XLS 1000 to come on when playing at reference level. Admittedly it's running the rear surround speakers, which is arguably a less demanding application than the front speakers.

I could be wrong (as usual but I have long suspected people need less power than they think they need. Even when running at reference level, because those 105 dB peaks (115 dB LFE) are short term events.

Great point (as usual ) MJHuman. I think a lot of people have way more power than they actually need. Reference levels are beyond what the majority of people listen to. I am all for overkill power in amplifiers as long as someone doesn't go broke in the process. I cannot imagine many people being able to actually use all 1000W at the same time, for a period the XPA-5 couldn't handle.

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post #12 of 421 Old 02-16-2011, 11:11 AM
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What is really the concern??

"How can the XPA-5 produce 200W RMS / Channel with all five channels driven?"

So what if it only does 175Watts?? how about 150Watts?

This is splitting hairs stuff which amounts to about 1dB of difference in SPL..

If you are concerned about 15Amp circuits, put a 20 amp in!! I never really understood why people do not have dedicated 20Amp circuits for audio anyways. Those standard 15A outlets in most rooms are 15Amps for all outlets which most people have a whole bunch of devices plugged into. Some rooms even run the lighting off the same 15Amp circuit.

If audio really matters then peope need to start with a dedicated 20amp circuit. Then you can go add another 20 amp circuit and maybe a 30amp circuit. Im adding that one this month for 8000Watts of peak power, my room will have 3 20 amp circuits and 1 30 amp circuit

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post #13 of 421 Old 02-16-2011, 11:12 AM
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Great point (as usual ) MJHuman. I think a lot of people have way more power than they actually need. Reference levels are beyond what the majority of people listen to. I am all for overkill power in amplifiers as long as someone doesn't go broke in the process. I cannot imagine many people being able to actually use all 1000W at the same time, for a period the XPA-5 couldn't handle.

In terms of bass requirements, most designs actually clip their amps for split seconds during the LFE demands that exist in movies. That has been a hot topic for years and people under estimate the power needed for clean dynamics.

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post #14 of 421 Old 02-16-2011, 11:31 AM
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In terms of bass requirements, most designs actually clip their amps for split seconds during the LFE demands that exist in movies. That has been a hot topic for years and people under estimate the power needed for clean dynamics.

Would this really matter if someone was running subwoofers either off of a pro amp or a self powered sub? I was just thinking that the XPA-5 would be used to drive 5 speakers down to 80Hz and the sub(s) picking up the low end. Appreciate you clearing this up for me!

I plan on building a reference level HT in a few years. It will be designed from the beginning to do that without too much strain. High Efficiency speakers and pro amps with way more power than I need. As much as I like the XPA series, I wouldn't consider it for this application. I would most likely go the route of MKtheater with pro JBLs (not his monster ones though ).

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post #15 of 421 Old 02-16-2011, 11:39 AM - Thread Starter
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Quote:
Originally Posted by MichaelJHuman View Post

This is what I think...

Their measurement was not for a long duration. The FTC used to call for 5 mins for the RMS measurement. To the best of my knowledge, Emotiva ignored this when talking about all channels driven (but they easily meet the two channel test I am sure, which is all that is really required to meet FTC rules.)

Based on what I have read, Emotiva tested their amps with a sweep. In other words, they ran the power from 0 to the stated THD with all channels driven over a short time. Also, they may have used a 1 khz test tone only (I believe they even stated this directly in some thread.)

Note that the power transformer rating is not a max rating, it's a power handling rating as far as I know. Which means the transformer may be able to do better than it's VA rating.

Also, it has reservoir caps in the power supply, quite a bit of capacitance. This helps it hold voltage to the output transistors as long as the charge is sufficient. In fact the power supply voltage is almost certainly quite a bit higher than is needed to do 200 watts RMS (40 volts RMS according to my calcs, is all that would be needed, or 57 V peak.) With my limited knowledge of electronics, it sure seems like they could provide very good dynamic headroom. I think it would come down to their limiter circuits and thermal circuits - if those were not in place, who knows what sort of power it could output before it blew up.

I don't think they are all that misleading. They say all channels driven, and I think their published data is legit as long as you understand that it's probably not 20hz to 20khz over a 5 minute time period. It's a ton of power in any case, IMO.

One more thing - some say they are conservative. I have to call BS on that. Look at their graphs. They are clearly limiting/clipping at the point where they measure power. Not that I am saying you can hear .01%THD. But look at the graphs and then come back and try to convince me it's a conservative measurement.

Nick at EMO stated that he ran a sweep test, and he measured up to 18 Amps at 120 Vac RMS sourced to the EMO XPA-5 off of the wall at Full Power rating with ALL FIVE CHANNELS DRIVEN!!

Most equipment that is on a 15Amp CCT. will be derated by 20%, so you will notice on most devices 12Amps Max. -- like your Hoover vacuum (120V, 60Hz, 12A). In fact, when the wifey runs the vac. line sag occurs and my lights dim, since lights are on the same cct., and thank goodness she did not plug in two vacs at once - back to the breaker box.

Also, notice the THD Power Output Rating (ACD) is 0.1%, of which is excellent at full power. You would play H__ hearing that distortion.
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post #16 of 421 Old 02-16-2011, 11:50 AM
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Quote:
Originally Posted by penngray View Post

In terms of bass requirements, most designs actually clip their amps for split seconds during the LFE demands that exist in movies. That has been a hot topic for years and people under estimate the power needed for clean dynamics.

Bass/LFE is another problem, I think.

I presume many people forget that their powered sub has to handle LFE along with crossed over bass.

Your $500 subwoofers likely just don't have enough power to produce peaks with no clipping. It's a bit hard to know what's going on, as so few sub's publish a peak SPL level and the THD that SPL level was achieved at.

I am a bit surprised at how many people's AV budget does not provide for a decent sub, as I figured that was a pretty important piece of gear. Admittedly I am getting by with an Emo Ultra-10, but I think it's pretty good for my needs, and I did just buy another one

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post #17 of 421 Old 02-16-2011, 11:52 AM
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Already numerous threads on this issue. Here's one: http://www.avsforum.com/avs-vb/showt...425&highlight=

I laughed pretty hard at the post where Chu tells MJH that he doesn't want to hear that he might've bought an 80wpc amp.
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post #18 of 421 Old 02-16-2011, 11:55 AM
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Quote:
Originally Posted by DenPureSound View Post

Nick at EMO stated that he ran a sweep test, and he measured up to 18 Amps at 120 Vac RMS sourced to the EMO XPA-5 off of the wall at Full Power rating with ALL FIVE CHANNELS DRIVEN!!

Most equipment that is on a 15Amp CCT. will be derated by 20%, so you will notice on most devices 12Amps Max. -- like your Hoover vacuum (120V, 60Hz, 12A). In fact, when the wifey runs the vac. line sag occurs and my lights dim, since lights are on the same cct., and thank goodness she did not plug in two vacs at once - back to the breaker box.

Also, notice the THD Power Output Rating (ACD) is 0.1%, of which is excellent at full power. You would play H__ hearing that distortion.

Don't forget that the current draw does not dicate output power, with a set of fully charged reservoir caps backing the output transistors. As long as the caps can hold supply voltage high enough for the duration of the test, the amp can put out more power than draw from the wall would indicate.

Also note that he's likely not giving you peak current draw. With AC voltage, you have a separate voltage/current cycle, with most of the charging occuring over a short time, and the amount of current should be dicated by the charge currently held by the caps. (This is explained pretty well somewhere in an article, but I forget where I read up on all this.)

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post #19 of 421 Old 02-16-2011, 11:57 AM - Thread Starter
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Quote:
Originally Posted by penngray View Post

What is really the concern??

"How can the XPA-5 produce 200W RMS / Channel with all five channels driven?"

So what if it only does 175Watts?? how about 150Watts?

This is splitting hairs stuff which amounts to about 1dB of difference in SPL..

If you are concerned about 15Amp circuits, put a 20 amp in!! I never really understood why people do not have dedicated 20Amp circuits for audio anyways. Those standard 15A outlets in most rooms are 15Amps for all outlets which most people have a whole bunch of devices plugged into. Some rooms even run the lighting off the same 15Amp circuit.

If audio really matters then peope need to start with a dedicated 20amp circuit. Then you can go add another 20 amp circuit and maybe a 30amp circuit. Im adding that one this month for 8000Watts of peak power, my room will have 3 20 amp circuits and 1 30 amp circuit

Yes, exactly as I have a 20Amp cct. -- Heck, 8K Watts of Peak Power to drive what? Isn't that more POWER than IMAX Theaters? My ears are draining some fluids now... ouch.
Power being only one parameter does matter when your paying for it with hard earned dollars, how else could one analyze anything, which you can't do anyways since it seems to me all the mfg's. use different specs. to test their amps, and if you were to print out spec sheets from a few mfgs. and feed those into your spreadsheet, it would look like an inverted IRS form with no algorithms.
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post #20 of 421 Old 02-16-2011, 11:59 AM
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Quote:
Originally Posted by Easyaspie View Post

Already numerous threads on this issue. Here's one: http://www.avsforum.com/avs-vb/showt...425&highlight=

I laughed pretty hard at the post where Chu tells MJH that he doesn't want to hear that he might've bought an 80wpc amp.

He's a funny guy...

He's quite a regular on various audio forums all over the internet. I run into his posts via different google searches from time to time. He's always been pretty funny

I seem to recall something about him getting a temp ban for one of his infamous "graphics"

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post #21 of 421 Old 02-16-2011, 12:00 PM
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Quote:
Originally Posted by MichaelJHuman View Post

Bass/LFE is another problem, I think.

I presume many people forget that their powered sub has to handle LFE along with crossed over bass.

Your $500 subwoofers likely just don't have enough power to produce peaks with no clipping. It's a bit hard to know what's going on, as so few sub's publish a peak SPL level and the THD that SPL level was achieved at.

I am a bit surprised at how many people's AV budget does not provide for a decent sub, as I figured that was a pretty important piece of gear. Admittedly I am getting by with an Emo Ultra-10, but I think it's pretty good for my needs, and I did just buy another one

The problem with subs is that I don't know of a lot of people who have actually heard a REALLY good sub. Most of the subs I run across in peoples houses are boom machines that sound terrible. The owners always think they that is how they are supposed to sound! Ignorance is Bliss!!! I usually keep my mouth shut as I don't want to offend anyone.

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post #22 of 421 Old 02-16-2011, 12:04 PM - Thread Starter
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Quote:
Originally Posted by MichaelJHuman View Post

Don't forget that the current draw does not dicate output power, with a set of fully charged reservoir caps backing the output transistors. As long as the caps can hold supply voltage high enough for the duration of the test, the amp can put out more power than draw from the wall would indicate.

Also note that he's likely not giving you peak current draw. With AC voltage, you have a separate voltage/current cycle, with most of the charging occuring over a short time, and the amount of current should be dicated by the charge currently held by the caps. (This is explained pretty well somewhere in an article, but I forget where I read up on all this.)

Yeppers, those fully charged Secondary Caps of 60,000uF will only hold the voltage up for a short period of time, especially at my Volume Levels here Just kidding ya MJH.
You know why he is not stating Peak Current Draw he does not want to tell you that you will be heading to the breaker box more often, instead of the beer frig.
MJH --> V=Vo sin (wt)
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post #23 of 421 Old 02-16-2011, 12:11 PM
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An interesting point, I always thought, about power, was that some people have amps hooked up who's peak power exceeds their wall power rating by a lot.

But fuses never blow.

Could be because amps are limiting power and clipping. Could it also be an indication people are not using as much power as they think they are?

I have thought about how to test how close to clipping we are getting in our systems. I had a thought. If I built a very simple circuit to drop speaker level voltage down to something a sound card input could handle, and sampled at a high rate to a WAV file, I should be able to produce a program to analyze the WAV file for any sign of clipping.

It's not as simple as just sending a test signal in, because I want to see what's happening with a real movie played at about the limit I listen at (say 6 dB down from reference.)

"But this one goes up to 11"
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post #24 of 421 Old 02-16-2011, 12:29 PM - Thread Starter
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Originally Posted by MichaelJHuman View Post

An interesting point, I always thought, about power, was that some people have amps hooked up who's peak power exceeds their wall power rating by a lot.

But fuses never blow.

Could be because amps are limiting power and clipping. Could it also be an indication people are not using as much power as they think they are?

I have thought about how to test how close to clipping we are getting in our systems. I had a thought. If I built a very simple circuit to drop speaker level voltage down to something a sound card input could handle, and sampled at a high rate to a WAV file, I should be able to produce a program to analyze the WAV file for any sign of clipping.

It's not as simple as just sending a test signal in, because I want to see what's happening with a real movie played at about the limit I listen at (say 6 dB down from reference.)

Well, I have an idea... let's let "WATSON" figure it all out, Oops he's busy on Jeopardy right now, and kicking some A__. Go get 'em WATSON

MJH -- listening to some Stereo this AM via Napster streaming in, and still NO dedicated amp here yet, I find listening at around -20 to -15db is nice, but when I go to Sat/Cbl and run DD into all five channels I have to move to around -5 to 0 Ref. levels to get as much SPL out of the Klipsch's. This is where the dedicated amp running the Denon AVR on the front end should make all the difference for Sat/Cbl DD or other surround modes, I'm sure of that one.

I think the fuses don't blow because most are not even coming close to using all the avail. power that the amp. can dish out.
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post #25 of 421 Old 02-16-2011, 12:48 PM
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In theory, if you are raising volume for some sources over others, it just means that some sources are hotter than others (higher average signal level.) So I would think a dedicated amp helps for everything, if you calibration is normal (with 0 dB indicating 85 dB SPL / channel with a -20 dBfs signal.)

Watson is amazing. I program software for a living, and am VERY impressed with what IBM has done.

"But this one goes up to 11"
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post #26 of 421 Old 02-16-2011, 01:02 PM
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I couldn't care less about all this mumbo jumbo. All I know is that the XPA-3 does a fine job driving the fronts.

Thank you for your attention.

Evil is Good
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post #27 of 421 Old 02-16-2011, 01:19 PM - Thread Starter
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Originally Posted by MichaelJHuman View Post

In theory, if you are raising volume for some sources over others, it just means that some sources are hotter than others (higher average signal level.) So I would think a dedicated amp helps for everything, if you calibration is normal (with 0 dB indicating 85 dB SPL / channel with a -20 dBfs signal.)

Watson is amazing. I program software for a living, and am VERY impressed with what IBM has done.

I worked on IBM's first Ink Jet printer, but after 100 Million $ into the project they cancelled it. Guess that states what my Engr. grade was. Back then we sprayed Ink using a BathTub, can you believe that?

But don't forget, WATSON didn't even know that Toronto was NOT a US City w/ the biggest Airport, Duh... a little Algorithm problem
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post #28 of 421 Old 02-16-2011, 01:24 PM - Thread Starter
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Originally Posted by Easyaspie View Post

Already numerous threads on this issue. Here's one: http://www.avsforum.com/avs-vb/showt...425&highlight=

I laughed pretty hard at the post where Chu tells MJH that he doesn't want to hear that he might've bought an 80wpc amp.

Ah, heck at 80Watts/Ch. that's Eight Times more than Paul Klipsch said he needed back then, which was quoted that he only needed 10Watts to drive one of his speakers.
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post #29 of 421 Old 02-16-2011, 01:24 PM
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Fuses don't blow because
a. The peak power is rarely if ever (probably "never" for most of us) approached in real life. Especially for multi-channel systems. Even if it is, it would only happen on transient peaks, which are very, very fast to something like a fuse or breaker.
b. Which reminds me, they are usually breakers, not fuses, and very short surges will not trip them. Even a fast blow fuse will sustain very brief transients well over its capacity -- it takes time for the metal to heat up and blow.

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"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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post #30 of 421 Old 02-16-2011, 01:54 PM
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Quote:
Originally Posted by DenPureSound View Post

Well, I have an idea... let's let "WATSON" figure it all out, Oops he's busy on Jeopardy right now, and kicking some A__. Go get 'em WATSON

MJH -- listening to some Stereo this AM via Napster streaming in, and still NO dedicated amp here yet, I find listening at around -20 to -15db is nice, but when I go to Sat/Cbl and run DD into all five channels I have to move to around -5 to 0 Ref. levels to get as much SPL out of the Klipsch's. This is where the dedicated amp running the Denon AVR on the front end should make all the difference for Sat/Cbl DD or other surround modes, I'm sure of that one.

I think the fuses don't blow because most are not even coming close to using all the avail. power that the amp. can dish out.


Just to add to what MJH said, outboard amps won't affect the level issue. Your speakers must receive X amount of power to achieve Y SPL. If you have to turn up the volume control to achieve that SPL, you still are feeding the speakers EXCACTLY X power to achieve Y SPL. It cannot be any different in the physical world we inhabit. So if you add outboard amps, you'll still have to turn up between sources, and if you weren't clipping before, you may not see any real difference in sound at all. ALthough many to most of us might THINK we hear a difference after purchasing and installing new amps . . .
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