or Connect
AVS › AVS Forum › Audio › Receivers, Amps, and Processors › EMOTIVA Thread Q&A [TECHNICAL TALK ONLY]
New Posts  All Forums:Forum Nav:

EMOTIVA Thread Q&A [TECHNICAL TALK ONLY] - Page 560

post #16771 of 17192
Quote:
Originally Posted by RichB View Post

Quote:
Originally Posted by arnyk View Post

The apparent suggestiion that I've never done such a thing is overlooked. ;-)

OK, lets do that::



This is a speaker that has been pointed out as being potentially problematical, but it fails to support the claim.



This is another speaker that has been pointed out as being potentially problematical, but it fails to support the claim.

A comment about the physics of the situation. When a speaker's impedance curve is minimum, the minimum impedance value is usually set by the DC resistance of the voice coil. But the DC resistance being a DC resistance is low on reactance so the phase angle is rapidly decreasing around this point.

Here is the Stereophile review of Thiel 3.7 speakers with a 90 DB efficiency specification.

http://www.stereophile.com/content/thiel-cs37-loudspeaker-measurements


Thank you for providing more counter-evidence for your as yet unsubstantiated claim about 4 ohm load and 45 degree phase angles. Note that the speaker is more of a resisitve load than most, and it is also highly atypical. Of course there are always a few outlyers, but basing general recommendations on them seems unwise.
Quote:
AVR's for example, do have difficulties delivering high currents.

That would be yet another undocumented assertion. It only would create an audible situation if it occurred while playing music or drama, which excludes any evidence based on testing with pure sine waves.
Quote:
External amps like many of those sold by Emotiva, have high current capability.

Evidence?

BTW the following would be an example of proper evidence for the above claim, but totsa luck finding a power cube for any Emotiva product.

http://www.audiograph.se/Downloads/PowerCube_12p_brochure_complete.pdf



Here is a power cube for a low cost stereo power amplifier - probably not that different from many AVRs:

http://theaudiocritic.com/plog/index.php?op=ViewArticle&articleId=22 There is really no current limiting fo loads with phase angles of up to 60 degrees.



Thanks again for helping me substantiate my claims.

Congratulations upon piling up such a large stack of unsubstantiated and exceptional claims with so few posts! ;-)
post #16772 of 17192
Quote:
Originally Posted by cavchameleon View Post

So, here is my situation. I also have very low sensitivity speakers (86db), NHT Classic Fours, 6 ohm nominal impedance. My AVR puts out 140W/channel (Denon AVRA100/4311). At reference the 140 is not enough power for these speakers. Room is not large, but heavily treated with broadband traps (the whole wall behind the speakers is treated as is the wall behind the seating area), plus tri-corners. So I calculated speakers as being 'away' from the walls due to the traps. Also, my seating position is just between 9 and 10 feet, I used 9. Putting my specs in the calculation, using an outboard amp - yes, I needed it anyway since running 11.1 and the AVR only provides 9 channels of amplification). Calculation taken from:

http://myhometheater.homestead.com/splcalculator.html



Notice that even with 300 watts of power I can only get 105 db (which is fine as that fits the THX recommendation of 85db for normal listening with 105db peaks). The Subs do hit louder (they are 94db efficient). Using the same calculator, my subs can hit 113db.

Bottom line is that in my room I do need more amplification if I want to hit reference levels. If I only used the AVR's power (and that's if it can actually provide the 140 watts since I'm using all the amps), I would only hit 101.7db, which falls short of THX requirements.

I guess that's what I get for having inefficient speakers, but I like their sound and it works well in my room/setup. I am using an outboard Emotiva amp (was great bang for the buck, especially on sale).

Do you really put your speakers in the middle of a large room?
post #16773 of 17192
Quote:
Originally Posted by ambesolman View Post


Yeah, that guy loooves to argue. Just picks apart posts trying to stir **** up. He had an exhaustive back and forth a while back with another obnoxious member in the paradigm owner's thread. Think they were both asked to leave, but know the other guy was. All that was needed was for them to agree to disagree, but that dude loves a dead horse😒

Talking about someone as if they won't see it is a classic example of the passive aggressive behavior that was complained about above. It is obviously not about the words but rather about whose ox is getting gored.

Fact is I only involved myself with the Paradigm speakers thread because I was begged to in a PM.

It appears with some that no good deed goes unpunished. ;-)
post #16774 of 17192
Quote:
Originally Posted by arnyk View Post

Thank you for providing more counter-evidence for your as yet unsubstantiated claim about 4 ohm load and 45 degree phase angles. Note that the speaker is more of a resisitve load than most, and it is also highly atypical. Of course there are always a few outlyers, but basing general recommendations on them seems unwise.
That would be yet another undocumented assertion. It only would create an audible situation if it occurred while playing music or drama, which excludes any evidence based on testing with pure sine waves.
Evidence?

BTW the following would be an example of proper evidence for the above claim, but totsa luck finding a power cube for any Emotiva product.

The upper level Emotiva amps have sufficient hardware to produce current and have been measured well.
I like Power Cube measurements (and my A51 does very well) but the fact the this particular test has been applied to their amps proves nothing. If they had been tested and failed, that would be some evidence.

Are you trying to bomb throw and have a bone to pick with Emotiva amps?
The insinuation is: Emotiva amps are inferior but of course, your 50 watt AVR has ample power.
You have proven everything with your Power calculator tongue.gif

Show me the power curve of a 100 watt AVR tongue.gif

http://www.audiograph.se/Downloads/PowerCube_12p_brochure_complete.pdf



Here is a power cube for a low cost stereo power amplifier - probably not that different from many AVRs:

http://theaudiocritic.com/plog/index.php?op=ViewArticle&articleId=22 There is really no current limiting fo loads with phase angles of up to 60 degrees.



Thanks again for helping me substantiate my claims.
[/Quote]

If you think your the Thiel 3.7 substantiate your claim and post insisting that your power calculator proves something, I think you are deluding yourself.

Quote:
Originally Posted by arnyk View Post

Congratulations upon piling up such a large stack of unsubstantiated and exceptional claims with so few posts! ;-)

I am comfortable in claiming that the a persons particular speaker, their impedance curve, phase angles, listen room should be examined for users who wish to avoid clipping and compression when listening to music and movies. I have presented links to credible and well writtness articles.

You position is unintelligible.
It seems like you are here to snipe. Personal attacks are not elevating your arguments nor your reputation.
I recommend you go over to Audioholics, there are some very knowledgeable folks over there.
You might learn something.

- Rich
post #16775 of 17192
Quote:
Originally Posted by RichB View Post


The upper level Emotiva amps have sufficient hardware to produce current and have been measured well.

No evidence,, again.

Hey I can make up stories about my favorite hardware, too. ;-)
post #16776 of 17192
Quote:
Originally Posted by arnyk View Post

No evidence,, again.

Hey I can make up stories about my favorite hardware, too. ;-)

I do not own an Emotiva amp, but many have good experiences with them.
I would not come onto an Emotiva thread and bad mouth them without a shred of evidence.

Here are two excellent reviews of the XPR-1:

HomeTheaterHifi driving Carver Ribbom speakers:

http://www.hometheaterhifi.com/power-amplifiers/power-amplifiers-reviews/emotiva-xpr-1-monoblock-power-amplifier/page-4-on-the-bench.html

Audioholics:

http://www.audioholics.com/amplifier-reviews/emotiva-xpr1-amplifier/emotiva-xpr1-amplifier-measurements

Just because there has not been a power curve measurement does not mean that these are not going to perform well. It just means that measurement has not been performed.

The design is completely laid out so that I believe the burnden of proof is that they are not fully capable of performing exceptionally well.

That insinuation from a guy claiming all amps sound the same is at best illogical.

- Rich
Edited by RichB - 1/4/14 at 1:11pm
post #16777 of 17192
Quote:
Originally Posted by RichB View Post

Quote:
Originally Posted by arnyk View Post

No evidence,, again.

Hey I can make up stories about my favorite hardware, too. ;-)

I do not own an Emotiva amp, but many have good experiences with them.
I would not come onto an Emotiva thread and bad mouth them without a shred of evidence.

I have not bad mouthed anything without reliable facts from some source other than my little imagination to back me up. The worst thing I have said about Emotiva amps was based on their own spec sheets.

You seem to see reports of reactive load performance measurements on amps that are not actually present. The Carver speaker impedance curve shows once again that your claims of 4 ohm speakers with 45 degree phase angles remain unsubstantiated. You are working hard to receive an "Emperor's Clothes" award on that count. ;-)
Quote:
Just because there has not been a power curve measurement does not mean that these are not going to perform well. It just means that measurement has not been performed.

That's speculation on your part, not adequate documentation. But do continue to entertain with made-up technical facts. ;-)
Quote:
The design is completely laid out so that I believe the burden of proof is that they are not fully capable of performing exceptionally well.

Yeah, yeah, yeah, your truth has thus far been based on just your intuitive feelings. Fact is that errors have been made and corners have been cut, even when it seemed improbable or unlikely. Thats why there are independent tests.

However, the real problem is the apparent belief that AVRs aren't also laid out so that they can't deliver adequte current to real world reactive loads. Your proof of that claim appears to be equally speculative.
Quote:
That insinuation from a guy claiming all amps sound the same is at best illogical.

Yet another made up fact - the very idea that I claim that all amps sound the same! You find that claim, fella... You just try!

I now see a new strategy, gross me out based on my love of reliable information and documented facts. :-(
Edited by arnyk - 1/4/14 at 5:56pm
post #16778 of 17192
Quote:
Originally Posted by arnyk View Post

I have not bad mouthed anything without independent facts to back me up. The worst thing I have said about Emotiva amps was based on their own spec sheets.
You seem to see reports of reactive load performance measurements on amps that are not actually present. The Carver speaker impedance curve shows once again that your claims of 4 ohm speakers with 45 degree phase angles remain unsubstantiated. You are working hard to receive an "Emperor's Clothes" award on that count. ;-)
That's speculation on your part, not adequate documentation. But do continue to entertain with made-up technical facts. ;-)
Yeah, yeah, yeah, your truth has thus far been based on just your intuitive feelings. Fact is that errors have been made and corners have been cut, even when it seemed improbable or unlikely. Thats why there are independent tests.

However, the real problem is the apparent belief that AVRs aren't also laid out so that they can't deliver adequate current to real world reactive loads. Your proof of that claim appears to be equally speculative.
Yet another made up fact - the very idea that I claim that all amps sound the same! You find that claim, fella... You just try!

I now see a new strategy, gross me out based on my love of reliable information and documented facts. :-(

You stated that Emotiva did not have any power curve measurements insinuating that they would no do well.
You are the man without facts and made over-reaching statements about power as if it could be throughly calculated using an INTERNET app without any regard to the speaker or room size.

When I present that to you, your style is to attempt to marginalize me so know one realizing what that this is merely internet off-gassing.

I have shown you reviews and measurements of difficult speakers proving that the speaker should not be ignored.
Then, you attack me assuming I own Emotiva in an attempt to paint me as a fan-boy.

This conversation is non compos mentis.
Therefore, I will assume the role as the adult in the room and end it.
Never again, shall I directly quote or address you.

To the others out there, I do believe that a seperrate amp can have value, especialy with capable speakers for 2 channel listening.
If you can find a review of your speakers, examine the impedance and phase characteristics.
There have been many AVR users who have benefited by imrpoved power because AVR;s can clip more often than you think and that can reduce dynamics before you detect audible distortion.

- Rich
Edited by RichB - 1/4/14 at 10:35pm
post #16779 of 17192
^
Is there any real world data out there that actually shows how much of a problem amp clipping and/or speaker compression is or is not? How can the average consumer make sure that his combination of amp, speaker and listening level is adequate?
post #16780 of 17192
Quote:
Originally Posted by markus767 View Post

^
Is there any real world data out there that actually shows how much of a problem amp clipping and/or speaker compression is or is not? How can the average consumer make sure that his combination of amp, speaker and listening level is adequate?

It's not a problem for most.
It depends on your listening habits, speakers characteristics, and room.

- Rich
post #16781 of 17192
^
Not what I was asking. The question was, "How can the average consumer make sure that his combination of amp, speaker and listening level is adequate?"
post #16782 of 17192
Quote:
Originally Posted by markus767 View Post

^
Not what I was asking. The question was, "How can the average consumer make sure that his combination of amp, speaker and listening level is adequate?"

By listening for distortion at loud levels and feeling for overheating of the amplifiers. If these things aren't a problem (they usually are not) then all is well. Amplifier is one of the least important things in a home audio system and yet seems to be the one that causes the most consternation. Curious.
post #16783 of 17192
^
It has been show that our hearing can tolerate a tremendous amount of distortion hence it can't be used as a replacement for measuring instruments. And, how is the amount of dissipated energy related to the performance of an amplifier?

The question remains: "How can the average consumer make sure that his combination of amp, speaker and listening level is adequate?"
post #16784 of 17192
Quote:
Originally Posted by markus767 View Post

^
It has been show that our hearing can tolerate a tremendous amount of distortion hence it can't be used as a replacement for measuring instruments. And, how is the amount of dissipated energy related to the performance of an amplifier?

The question remains: "How can the average consumer make sure that his combination of amp, speaker and listening level is adequate?"

It is a great question with no good answer.

My friend had a two channel system with a Pioneer SC-07, B&W CM7 speakers, and Martin Logan Grotto I sub.
Occasionally, he listens to loud music.Very loud.

The SC-07 was the original ICE amp with soft clipping.
There was a point (-10) where it got louder but did not sound very dynamic

He upgraded to a BDP-105 used as a preamp and two Outlaw 2200 (200 WPC) mono blocks.
The difference was striking. The dynamics were much improved and the system is not turned up more than 3/4.

From Sound and Vision the CM series impedance: minimum/nominal) front left/right: 3.1 / 7 ohms

This was a real eye-opener to me.
To be fair, AH measured this receiver and found issues handling low impedance loads which appears to have been corrected in the newer models.

A room size calculator can be a good starting point, but If I wanted to be more certian, I would try to find impedance/phase measurements.
My personal opinion, is that if you like listiening to music, play it loud, have good speakers, like high-dynamic range music, look into getting an external amp.


- Rich
post #16785 of 17192
Quote:
Originally Posted by FMW View Post

By listening for distortion at loud levels and feeling for overheating of the amplifiers. If these things aren't a problem (they usually are not) then all is well. Amplifier is one of the least important things in a home audio system and yet seems to be the one that causes the most consternation. Curious.

A dealer once told me that amplifier seem to be primarily a male obsession. wink.gifbiggrin.gif

- Rich
post #16786 of 17192
Quote:
Originally Posted by RichB View Post
 
My personal opinion, is that if you like listiening to music, play it loud, have good speakers, like high-dynamic range music, look into getting an external amp.

 

My personal opinion, is that if you like listening to music, play it loud, have good speakers, like high-dynamic range music, look into getting an external amp if the amp you already have cannot power your system to the SPLs you require without clipping. 

post #16787 of 17192
Quote:
Originally Posted by RichB View Post

It is a great question with no good answer.

Why would there be no good answer? Is speaker compression and amp clipping something that can't be measured?
post #16788 of 17192
Quote:
Originally Posted by kbarnes701 View Post

My personal opinion, is that if you like listening to music, play it loud, have good speakers, like high-dynamic range music, look into getting an external amp if the amp you already have cannot power your system to the SPLs you require without clipping. 

It is the determination of without clipping that is the trick.
I beleive that most folks likely do not push their systems so there is no issue.

But when an amplifier runs out of gas for a peak, you will not hear clipping. You will likely not notice any problem at all.
Most well designed amps will simply limit that peak and continue right along sounding very good.
Not many turn up their system into gross distortion.
It seems reasonable that before gross distortion sets in, the sound may flatten out.

If you do not want any amplifier induced compression, they you have to analyze your system.

In terms of tempurature, I ran some bass heavy content and measured the tempurature of the A51 heat sinks.
It hit 129 at -10 and 150+ F at -3. The volume level was beyond anything I require or recommended by OSHA. tongue.gif



Still, It would be fun to put try some insanely powerful monoblocks.

- Rich
post #16789 of 17192
Quote:
Originally Posted by markus767 View Post

Why would there be no good answer? Is speaker compression and amp clipping something that can't be measured?

I do not know a simple way to do it.

If you love music uncompressed source and nice speakers, then you should try to analyze your needs.

- Rich
post #16790 of 17192
Quote:
Originally Posted by RichB View Post

Most well designed amps will simply limit that peak
Which is the definition of clipping...
post #16791 of 17192
Quote:
Originally Posted by Tom Grooms View Post

Which is the definition of clipping...

Absolutely, but I wonder if folks can hear sound that is no produced.

Many people think they will hear clipping and you could argue it is distortion as well.
But most discussion centers around distortion becoming audible are thinking about the sound becoming nasty.

Some folks, might like the compressed sound better. Think tubes tongue.gif

- Rich
post #16792 of 17192
Quote:
Originally Posted by RichB View Post

I do not know a simple way to do it.

So what's the NOT simple way to do it?
post #16793 of 17192
Quote:
Originally Posted by markus767 View Post

So what's the NOT simple way to do it?

Use an oscilloscope. It is still pretty easy if you have that equipment.
post #16794 of 17192
Quote:
Originally Posted by RichB View Post

A dealer once told me that amplifier seem to be primarily a male obsession. wink.gifbiggrin.gif

- Rich

I believe that. Bigger, stronger, faster, more powerful, able to leap tall buildings with a single bound. All male motivations.
post #16795 of 17192
If you can, establish a baseline efficiency.
I have not yet done this, but you can measure the voltage at the speaker for 1 watt based on the impedance of your speakers and measure the SPL.

I used the Stereophile measurments which are stated at 87 DB but since the Salons are 4 ohms for most of the range, the estimate was 2 watts.
So, I used 84 DB as a baseline.

There are tons of calculators out there but with room gain, I get the following results:

Speaker Sensitivity: 84 dB SPL (1 W/1 M)
Amplifier Power: 400 Watts (A51 into 4 0hms)
Distance: 10 feet
No. of Speakers: 2
Near a wall (within 2 to 4 feet)

Resutls
26 DB Gain from Amplifier
-9.7 DB Loss from distance
3 DB gain from sound reinforcement
3 DB gain from speaker placement
106.7 DB at listening position.

The trouble is at the high end power goes up at an alarming rate.
I go with the THX specification of 85 DB and 20 DB headroom as a target.
Here is a decent article about real amplifier power:

http://www.acousticfrontiers.com/home-theater-blog/2013/3/22/spl-calculator

What you can take away from this is there is a lot of slop in these numbers but one thing is clear:

For a two channel system, the power required is beyond anything anything I can find in an AVR.

- Rich
post #16796 of 17192
Quote:
Originally Posted by FMW View Post

By listening for distortion at loud levels and feeling for overheating of the amplifiers. If these things aren't a problem (they usually are not) then all is well. Amplifier is one of the least important things in a home audio system and yet seems to be the one that causes the most consternation. Curious.



OK,
I'm not here to bash. But the statement is complete incorrect. In my personal experience I have heard a difference in the quality of music reproduced using different amps given that everything else remain the same. The biggest difference in the amps I could hear is the reproduction of the bass frequencies. The fact is if an amplifier does not have sufficient current capability and an low damping factor is just going to sound bad.
As for reproduction of high frequencies, the design of the amp will directly influence the clarity of the music. The amount of negative feedback used within an amp can slow down the speed of amplification thus reducing the clarity of the reproduce So any amplifier used for music / sound reproduction must have: High Current capability, High speed amplification, High damping factor, Low negative feedback, prefer none, flat frequency response, and vary low distortion.
post #16797 of 17192
Quote:
Originally Posted by FMW View Post

Use an oscilloscope. It is still pretty easy if you have that equipment.

I haven't done this yet, but I plan to adjust the volume to 2.83 volts.
Since my speakers are 4 0hms, that should be 2 watts.
Measure the SPL using the OmniMic at my listening position.

Use these numbers to compute the Power and SPL table.

A friend of mine has Oscium for his iPad, I would I use that to measure actual power?

- Rich
post #16798 of 17192
Quote:
Originally Posted by FMW View Post

Use an oscilloscope. It is still pretty easy if you have that equipment.

This is your answer to the question "How can the average consumer make sure that his combination of amp, speaker and listening level is adequate?"?
post #16799 of 17192
Quote:
Originally Posted by markus767 View Post

This is your answer to the question "How can the average consumer make sure that his combination of amp, speaker and listening level is adequate?"?

It appears there is nothing wrong with your reading skills other than taking the statement out of context. I was answering the question of how one knows when an amplifier is clipping. That is how it is done. The alternative would be to use a pro audio amp that has a clipping indicator.
post #16800 of 17192
Quote:
Originally Posted by FMW View Post

It appears there is nothing wrong with your reading skills other than taking the statement out of context. I was answering the question of how one knows when an amplifier is clipping. That is how it is done. The alternative would be to use a pro audio amp that has a clipping indicator.

And how exactly do you do it? Does a clipping indicator on a "pro audio amp" reliably show clipping?
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Receivers, Amps, and Processors
AVS › AVS Forum › Audio › Receivers, Amps, and Processors › EMOTIVA Thread Q&A [TECHNICAL TALK ONLY]