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post #211 of 824 Old 02-14-2012, 03:26 PM - Thread Starter
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Ha, is it merely coincidence that we have a lot of mention of quality since someone asked about Cerwin-Vega speakers?

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Originally Posted by saldog78 View Post

I applaud the effort in this thread, i just don't think it's overly useful, and in fact could be quite misleading to someone new to the forum.

Thanks. Well, let me provide some context, and maybe you can help make it less misleading.

Maybe my earliest statements of "Why this list?" are incomplete?

I've read thousands of speaker reviews, marketing pages, test reports, and anecdotes about speakers, and I've listened to a smattering of consumer "hi-fi" speakers. This information contained talk about fluffy meaningless stuff that were just positive adjectives thrown together. Or they tested the smoothness of on and off-axis response. Or how much distortion at 90dB there was. And how beautiful the cabinetry was.

What they usually failed to mention was how the speaker performs at higher volumes, like at 10dB below reference level and above.

So I don't think the world needs more information about the qualitative attributes that present themselves when you're not taxing the speaker at all. You can read the manufacturer's fluff about the speaker. You can find the owners' threads (where most people feel they're happy, because they bought the product). You can read honest reviews. You can listen to the speakers yourself. And you can sometimes find test data.

I think the world needs more info about the stuff that's usually left out. I found a few threads here and there talking about how speakers do and don't perform on dynamic peaks. And how a surprising number of people are stressing their speakers / amps out and getting a LOW QUALITY performance. But the info was few and far between.

I never claimed that "This list presents all the universally-acclaimed speakers of high quality on all attributes and goals."

Another purpose of the list is educational. Many people don't realize how their speakers are compressing their dynamic peaks and distorting.

Quote:
Originally Posted by saldog78 View Post

Your spreadsheet is completely ignoring sound QUALITY. What good is playing loud if it sounds terrible?

Note that above when I decided to cut the list off on the bottom at 105dB using peak watts @ 12 feet, I added that many of the speakers I was dropping had many fine qualities. They aren't bad speakers. They're not good enough for this particular application. That's true about everything in life. People, cars, guns, houses, etc.

One of the qualities of a speaker is how it performs how people are using it. If you give me a speaker with a perfect frequency response, and I want to listen at -15dBfs (which is less than half as loud as in a movie theater), and the dynamics of the music are all squashed, or my amp clips a bit making the sound harsh, or that perfect frequency response changes due to compression, than this speaker is now performing poorly, and exhibits low quality for how I'm trying to use it.

Imagine a world with reviews of automobiles, without any max performance info... They extol the virtues of these fine cars: their beautiful paint jobs, how quiet they are to drive, how they felt to drive, how well the brakes worked......ALL UNDER 60 MPH! I'd feel like something was missing if I didn't find out what the limits of the vehicles were. Fine, you told me how they accelerate in town when I'm going to the grocery store. But how will it accelerate if I tromp on the accelerator pedal? Is the handling responsive at higher speeds? Is the top speed only 60? 70? Will I get creamed trying to pass a truck on the interstate?

Such a review with missing info might rate a 1930s car the same as a modern BMW, because you never put the vehicles into a situation that stressed them.

Can you imagine someone wanting to know what the quality of the car's performance limits are? And if you replied, "Well, who cares about if the car can do 100mph if the quality of the car sucks?"

Many of the speakers on the list have a poorer frequency response than certain models by Revel and Paradigm and Magnepan. But many other speakers do, too. Someone's making these speakers for a reason, because they think they can sell them to some niche. They have their strong and weak points. I'm pointing out that the Revel has some weak qualities. It's up to you to decide if that matters to you. If you turn the dial on your receiver no higher than -10 and you sit 12 feet away, then I imagine it shouldn't matter.

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Originally Posted by saldog78 View Post

For example, Revel Ultima Salon 2s, some of the most highly regarded speakers in the world, only have an 86 db/W/m sensitivity. You're going to dock them because they're tough to drive?

Well, they're in the upper-80s, which seems to be middlin' in the consumer speaker world. And to be clear, I'm only using the manufacturers' own specs in the chart, except where it's known/assumed those specs are incorrect. I've only compiled them here to look at in one place.

When I "scored," it's only as a way to aggregate several of their attributes together, with different weightings. But how the chart is ranked by default is by a combination of their power handling, sensitivity, and output. Really, I could just rank on output, since that's a combination of power handling and sensitivity.

If the Revel Ultima Salon 2 can handle 800 watt peaks, then it'll be ranked higher on the list...higher even than some higher sensitivity speakers.

Have your read RMK's review of his JTR speakers? Here are more comments on AVS. He's someone who says he upgraded going from the Revel to JTR.

Product Disclosures on Quality
I also noticed how much more information about the speakers' quality was given on many pro audio websites. They're willing to tell me how the speaker will experience thermal compression. How much distortion there is at what level. What the frequency response looks like. And off-axis, too. What the polar response is. What the impedance curve is. When companies do this, they're responding to their customers' demand for more information about the speaker's quality. We see this less in the consumer world...why? Are we a sucker for prettier cabinetry and fluffy marketing?

Quote:
Originally Posted by saldog78 View Post

If "ease of driving" is your only criteria, why not just everybody buy PA speakers and call it a day? They're cheap, handle lots of power, and produce tons of db. Oh wait, they sound terrible, because of the non-linear response, etc.

No, ease-of-driving isn't the only criteria to make the list. As I've talked about elsewhere, it's: Can this speaker output 105db using its own stated peak power handling. That might be lower ease-of-driving. Or it might be able to handle a lot of power, so one can mate it with a 200-400wpc amp.

Another aspect of a linear response is: as I turn up the volume, is the frequency response the same?

There are a lot of pro speakers: concert live sound speakers of various qualities, nearfield monitoring, midfield monitoring, farfield monitors. Stage monitors. Some of those are the speakers used by the people that MADE the records and movies you're listening to!

Distortion
Also note that distortion rises as you stress the speaker. If you're not stressing the speaker, then there shouldn't be a whole lot of distortion. Distortion sounds bad...it's another qualitative attribute. Pushing an amp into clipping on dynamic peaks causes distortion. There's thermal compression and distortion when your average levels are too high. Distortion due to magnetic flux changes under peak duress, or mechanical limits of the speaker, make the sound bad!

People have well-regarded speakers here all the time that when they turn it up so it's 10db lower than movie theater reference level, the sound is harsh. They wince. They complain it sounds "too loud." With better speakers for those levels, they no longer say it's too loud. It's louder, and impactful. They get scared by the movies. They can feel the music's bass. It sounds more dynamic like listening to the orchestra live. They have a higher quality performance than what they had before.

Quote:
Originally Posted by saldog78 View Post

I'm just trying to figure out the usefulness of this thread, because i came into it with high expectations (and i definitely appreciate all the work you've put in!), but i just want people to keep it in perspective that the sound actually has to sound GOOD, not just loud.

Well, I imagine you came into the thread expecting to find a list of speakers that have higher sensitivity, and also more SPL, and lower distortion, with regards to reference level output.

Depending on your application, louder is gooder. Light background music: 1 w of power and a low sensitivity speaker is fine. Critical listening at 10 feet with an extremely quiet room (so the noise floor is low), again, a few watts and less sensitivity is fine. But if you want it to sound like the concert, or the movie theater, or you're at a greater listening distance, then we're making greater demands on the speakers.

And there are other qualitative attributes that may not apply for other people. Off-axis performance? Not needed for those with heavily treated reflection points. Wide sweet spot? Not needed for those sitting in a single listening point alone. Furniture grade cabinetry? Who cares, if the speaker is hidden? Higher distortion? If they're outdoor on a noisy lake, I probably won't notice.

Here's how you can help:
  • Find some more speakers that don't crumble when pushed harder, that you feel exhibit a high degree of quality in many other aspects as well. An 85db sensitive (anechoic) speaker that has 600 watt peak power handling (or probably 150w RMS power handling) will make the list. As will a 91db speaker and 300 watts peak.
  • Tell me if you think that near-reference-level, like 5dB under, is worth keeping on this list?
  • Find forum sentiment about how people feel about certain speakers, so it can be noted here. Find enough positive or negative reviews that we can agree on how people feel about the speaker.
  • Tell me what other qualitative measurements you'd like to see. I do want to learn more about directivity index / factor, and how it should be presented. For instance, for subwoofers, this has been THD at different frequencies; the -3db point; Max SPL < some distortion threshold for 10-20hz, 10-40hz, 20-60hz, 20-120hz; group delay, etc.

I appreciate your feedback and letting me explain more about the context of the list, why it's made, what it's trying to help with, and what it doesn't do. And I thank you in advance for help in making the info more clear, presentable, realistic, and complete!
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post #212 of 824 Old 02-14-2012, 06:17 PM
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Thanks for the responses. I see your perspective, i just wanted to make sure it was understood that a speaker may look great on paper but still sound like crap in reality (or vice versa).

I do see the value in such a list, as long as it's qualified with a statement about making sure to listen to speakers before you buy them, as sound quality can vary, and may depend significantly on personal preference.

Again, thanks for your effort. And if you want to add to the active speaker list, i may suggest the Mackie HR824mkII

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post #213 of 824 Old 02-16-2012, 06:37 PM - Thread Starter
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Added the MK S-150 and the MK LCR-750.

Added Crystal Acoustic TX-T2 and TX-T3 (what's the price on this speaker?)
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post #214 of 824 Old 02-16-2012, 07:03 PM
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Quote:
Originally Posted by saldog78 View Post

I applaud the effort in this thread, i just don't think it's overly useful, and in fact could be quite misleading to someone new to the forum. Your spreadsheet is completely ignoring sound QUALITY. What good is playing loud if it sounds terrible? For example, Revel Ultima Salon 2s, some of the most highly regarded speakers in the world, only have an 86 db/W/m sensitivity. You're going to dock them because they're tough to drive? If "ease of driving" is your only criteria, why not just everybody buy PA speakers and call it a day? They're cheap, handle lots of power, and produce tons of db. Oh wait, they sound terrible, because of the non-linear response, etc.

I'm just trying to figure out the usefulness of this thread, because i came into it with high expectations (and i definitely appreciate all the work you've put in!), but i just want people to keep it in perspective that the sound actually has to sound GOOD, not just loud.

Revel Salon 2s may sound nice to you but at that price they're not ever going to be seriously considered by very many. At that price they should give you a blowjob...every frikkin' day.

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post #215 of 824 Old 02-16-2012, 07:10 PM
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Quote:
Originally Posted by Eyleron View Post

Added the MK S-150 and the MK LCR-750.

Added Crystal Acoustic TX-T2 and TX-T3 (what's the price on this speaker?)

The T2's are 859 delivered (I bought them) and I think the 3's are 1059 but would have to confirm. A hell of a bargain if you ask me which I know you didn't.
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post #216 of 824 Old 02-17-2012, 05:51 AM
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this thread is extremely useful!!!...and wish I had it when I was searching for speakers!!!...this is the perfect start for someone looking to get into high sensitive speakers for ht or even music listening...after looking at the spreadsheet...you then check all different forums for reviews to narrow down your choice or even get a chance to listen to one before purchasing.

I had aperion speakers and they sounded like garbage playing at high volumes...fine for lower volumes but I like reference sound...I like to be in the front row of a music concert...I like to be in the middle of a train wreck, like in Super 8. You play stuff like that, and many, not all, low sensitive speakers at high volume may sound like crap...my aperions did.

In fact, I even prefer the high sensitive speakers for music...I find myself listening to music more then I ever did....and some of the very high dollar speakers seemed to be just that from what I have read on many comparisons between less expensive, high sensitive speakers to the stylish line of speakers.
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post #217 of 824 Old 02-17-2012, 07:55 AM
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Quote:
Originally Posted by lovinthehd View Post

Revel Salon 2s may sound nice to you but at that price they're not ever going to be seriously considered by very many. At that price they should give you a blowjob...every frikkin' day.

You may want to mosey on up to Music Lovers in SF and get a demo of the Salon2's. When properly setup, they are amazing speakers for music (probably the best I have heard). Listening to well recorded Jazz with a smokey voiced singer is a very nice experience. My Studio2/Voice2 LCR's were great loudspeakers and the cabinets were furniture grade so they look good in just about any shared space environment.

What these audiophile speakers lack is the ability to play movies and concerts at realistic levels. The train wreck scene in Super 8 is a good example as is Metalica playing Sandman or Iron Man (with Ozzie) at the the Rock&Roll Hall of Fame Concert Bluray. I was disappointed that my beautiful Revels could not give me that spine tingling sensation of a concert level audio system. They were kind of like a beautiful high maintenance woman, pretty to look at and fun to be out with but lacking authenticity. OK, maybe not the best analogy () but for me it came down to function over form. Not everyone wants this and it certainly can be damaging to your hearing if you're not careful, but I found what I was looking for in a HT sound system and can never go back to polite and pretty.

HToM

"Well, la di fricken da."!
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post #218 of 824 Old 02-17-2012, 08:50 AM
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Quote:
Originally Posted by Eyleron View Post

Ha, is it merely coincidence that we have a lot of mention of quality since someone asked about Cerwin-Vega speakers?


Thanks. Well, let me provide some context, and maybe you can help make it less misleading.

Maybe my earliest statements of "Why this list?" are incomplete?

I've read thousands of speaker reviews, marketing pages, test reports, and anecdotes about speakers, and I've listened to a smattering of consumer "hi-fi" speakers. This information contained talk about fluffy meaningless stuff that were just positive adjectives thrown together. Or they tested the smoothness of on and off-axis response. Or how much distortion at 90dB there was. And how beautiful the cabinetry was.

What they usually failed to mention was how the speaker performs at higher volumes, like at 10dB below reference level and above.

So I don't think the world needs more information about the qualitative attributes that present themselves when you're not taxing the speaker at all. You can read the manufacturer's fluff about the speaker. You can find the owners' threads (where most people feel they're happy, because they bought the product). You can read honest reviews. You can listen to the speakers yourself. And you can sometimes find test data.

I think the world needs more info about the stuff that's usually left out. I found a few threads here and there talking about how speakers do and don't perform on dynamic peaks. And how a surprising number of people are stressing their speakers / amps out and getting a LOW QUALITY performance. But the info was few and far between.

I never claimed that "This list presents all the universally-acclaimed speakers of high quality on all attributes and goals."

Another purpose of the list is educational. Many people don't realize how their speakers are compressing their dynamic peaks and distorting.


Note that above when I decided to cut the list off on the bottom at 105dB using peak watts @ 12 feet, I added that many of the speakers I was dropping had many fine qualities. They aren't bad speakers. They're not good enough for this particular application. That's true about everything in life. People, cars, guns, houses, etc.

One of the qualities of a speaker is how it performs how people are using it. If you give me a speaker with a perfect frequency response, and I want to listen at -15dBfs (which is less than half as loud as in a movie theater), and the dynamics of the music are all squashed, or my amp clips a bit making the sound harsh, or that perfect frequency response changes due to compression, than this speaker is now performing poorly, and exhibits low quality for how I'm trying to use it.

Imagine a world with reviews of automobiles, without any max performance info... They extol the virtues of these fine cars: their beautiful paint jobs, how quiet they are to drive, how they felt to drive, how well the brakes worked......ALL UNDER 60 MPH! I'd feel like something was missing if I didn't find out what the limits of the vehicles were. Fine, you told me how they accelerate in town when I'm going to the grocery store. But how will it accelerate if I tromp on the accelerator pedal? Is the handling responsive at higher speeds? Is the top speed only 60? 70? Will I get creamed trying to pass a truck on the interstate?

Such a review with missing info might rate a 1930s car the same as a modern BMW, because you never put the vehicles into a situation that stressed them.

Can you imagine someone wanting to know what the quality of the car's performance limits are? And if you replied, "Well, who cares about if the car can do 100mph if the quality of the car sucks?"

Many of the speakers on the list have a poorer frequency response than certain models by Revel and Paradigm and Magnepan. But many other speakers do, too. Someone's making these speakers for a reason, because they think they can sell them to some niche. They have their strong and weak points. I'm pointing out that the Revel has some weak qualities. It's up to you to decide if that matters to you. If you turn the dial on your receiver no higher than -10 and you sit 12 feet away, then I imagine it shouldn't matter.


Well, they're in the upper-80s, which seems to be middlin' in the consumer speaker world. And to be clear, I'm only using the manufacturers' own specs in the chart, except where it's known/assumed those specs are incorrect. I've only compiled them here to look at in one place.

When I "scored," it's only as a way to aggregate several of their attributes together, with different weightings. But how the chart is ranked by default is by a combination of their power handling, sensitivity, and output. Really, I could just rank on output, since that's a combination of power handling and sensitivity.

If the Revel Ultima Salon 2 can handle 800 watt peaks, then it'll be ranked higher on the list...higher even than some higher sensitivity speakers.

Have your read RMK's review of his JTR speakers? Here are more comments on AVS. He's someone who says he upgraded going from the Revel to JTR.

Product Disclosures on Quality
I also noticed how much more information about the speakers' quality was given on many pro audio websites. They're willing to tell me how the speaker will experience thermal compression. How much distortion there is at what level. What the frequency response looks like. And off-axis, too. What the polar response is. What the impedance curve is. When companies do this, they're responding to their customers' demand for more information about the speaker's quality. We see this less in the consumer world...why? Are we a sucker for prettier cabinetry and fluffy marketing?


No, ease-of-driving isn't the only criteria to make the list. As I've talked about elsewhere, it's: Can this speaker output 105db using its own stated peak power handling. That might be lower ease-of-driving. Or it might be able to handle a lot of power, so one can mate it with a 200-400wpc amp.

Another aspect of a linear response is: as I turn up the volume, is the frequency response the same?

There are a lot of pro speakers: concert live sound speakers of various qualities, nearfield monitoring, midfield monitoring, farfield monitors. Stage monitors. Some of those are the speakers used by the people that MADE the records and movies you're listening to!

Distortion
Also note that distortion rises as you stress the speaker. If you're not stressing the speaker, then there shouldn't be a whole lot of distortion. Distortion sounds bad...it's another qualitative attribute. Pushing an amp into clipping on dynamic peaks causes distortion. There's thermal compression and distortion when your average levels are too high. Distortion due to magnetic flux changes under peak duress, or mechanical limits of the speaker, make the sound bad!

People have well-regarded speakers here all the time that when they turn it up so it's 10db lower than movie theater reference level, the sound is harsh. They wince. They complain it sounds "too loud." With better speakers for those levels, they no longer say it's too loud. It's louder, and impactful. They get scared by the movies. They can feel the music's bass. It sounds more dynamic like listening to the orchestra live. They have a higher quality performance than what they had before.



Well, I imagine you came into the thread expecting to find a list of speakers that have higher sensitivity, and also more SPL, and lower distortion, with regards to reference level output.

Depending on your application, louder is gooder. Light background music: 1 w of power and a low sensitivity speaker is fine. Critical listening at 10 feet with an extremely quiet room (so the noise floor is low), again, a few watts and less sensitivity is fine. But if you want it to sound like the concert, or the movie theater, or you're at a greater listening distance, then we're making greater demands on the speakers.

And there are other qualitative attributes that may not apply for other people. Off-axis performance? Not needed for those with heavily treated reflection points. Wide sweet spot? Not needed for those sitting in a single listening point alone. Furniture grade cabinetry? Who cares, if the speaker is hidden? Higher distortion? If they're outdoor on a noisy lake, I probably won't notice.

Here's how you can help:
  • Find some more speakers that don't crumble when pushed harder, that you feel exhibit a high degree of quality in many other aspects as well. An 85db sensitive (anechoic) speaker that has 600 watt peak power handling (or probably 150w RMS power handling) will make the list. As will a 91db speaker and 300 watts peak.
  • Tell me if you think that near-reference-level, like 5dB under, is worth keeping on this list?
  • Find forum sentiment about how people feel about certain speakers, so it can be noted here. Find enough positive or negative reviews that we can agree on how people feel about the speaker.
  • Tell me what other qualitative measurements you'd like to see. I do want to learn more about directivity index / factor, and how it should be presented. For instance, for subwoofers, this has been THD at different frequencies; the -3db point; Max SPL < some distortion threshold for 10-20hz, 10-40hz, 20-60hz, 20-120hz; group delay, etc.

I appreciate your feedback and letting me explain more about the context of the list, why it's made, what it's trying to help with, and what it doesn't do. And I thank you in advance for help in making the info more clear, presentable, realistic, and complete!

Really nice posts and I couldn't agree more. Fact is that while I have the highest respect for those that say a good speaker is a good speaker, I think there is a difference between speakers that sound great at lower levels but worse as they are taxed and those that sound just fine when taxed.
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post #219 of 824 Old 02-17-2012, 09:56 AM
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This thread is a great idea, but the current spreadsheet has a couple significant miscalculations. As background, I have 15+ years experience with pro gear - sound reinforcement, live PA, high-current power amps, etc. So this is not some audiophile post about "which sounds better".

First, there is a well-known loophole in sensitivity ratings that is causing this spreadsheet to make it appear that Pro-series speakers have higher sensitivity than home speakers. They don't. Pro speakers run at 4 ohms, whereas home speakers typically run at 8 ohms. Manufacturers exploit this in measuring sensitivity:

http://www.diyaudio.com/wiki/Loudnes...er_Sensitivity

Quote:


Also, for an 8 ohm speaker, 1 watt input is 2.83 volts. Do you measure a 4 ohm speaker at 1 watt (1.42 volts) or at 2.83 volts (2 watts)? The latter method gives a result 3 dB higher, and is therefore popular with marketers.

Second, the spreadsheet weighs higher watts as being better, and lower as being worse. But the watts are directly related to the impedance! 500w @ 4 ohm is the same as 250w @ 8 ohm is the same as 1000w @ 2 ohm. There is no advantage to running at 4 ohm and using 500w vs 8 ohm and using 250w; this is merely a design choice by the speaker designer. In fact, the power supply requirements to pump 500w could be seen as a DISadvantage:

http://www.gcaudio.com/resources/howtos/spkramp.html

Bottom line, if you subtracted 3db from the 4 ohm speakers' sensitivity ratings, and re-weighted the wattage column as watts/ohms, you would see very different (and more realistic) results.
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post #220 of 824 Old 02-17-2012, 10:21 AM
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Quote:
Originally Posted by nizl View Post

This thread is a great idea, but the current spreadsheet has a couple significant miscalculations. As background, I have 15+ years experience with pro gear - sound reinforcement, live PA, high-current power amps, etc. So this is not some audiophile post about "which sounds better".

First, there is a well-known loophole in sensitivity ratings that is causing this spreadsheet to make it appear that Pro-series speakers have higher sensitivity than home speakers. They don't. Pro speakers run at 4 ohms, whereas home speakers typically run at 8 ohms. Manufacturers exploit this in measuring sensitivity:

http://www.diyaudio.com/wiki/Loudnes...er_Sensitivity



Second, the spreadsheet weighs higher watts as being better, and lower as being worse. But the watts are directly related to the impedance! 500w @ 4 ohm is the same as 250w @ 8 ohm is the same as 1000w @ 2 ohm. There is no advantage to running at 4 ohm and using 500w vs 8 ohm and using 250w; this is merely a design choice by the speaker designer. In fact, the power supply requirements to pump 500w could be seen as a DISadvantage:

http://www.gcaudio.com/resources/howtos/spkramp.html

Bottom line, if you subtracted 3db from the 4 ohm speakers' sensitivity ratings, and re-weighted the wattage column as watts/ohms, you would see very different (and more realistic) results.

thanks for an enlightening posts and I hope the adjustments are made.
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post #221 of 824 Old 02-17-2012, 10:40 AM
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Quote:
Originally Posted by RMK! View Post

You may want to mosey on up to Music Lovers in SF and get a demo of the Salon2's. When properly setup, they are amazing speakers for music (probably the best I have heard). Listening to well recorded Jazz with a smokey voiced singer is a very nice experience. My Studio2/Voice2 LCR's were great loudspeakers and the cabinets were furniture grade so they look good in just about any shared space environment.

What these audiophile speakers lack is the ability to play movies and concerts at realistic levels. The train wreck scene in Super 8 is a good example as is Metalica playing Sandman or Iron Man (with Ozzie) at the the Rock&Roll Hall of Fame Concert Bluray. I was disappointed that my beautiful Revels could not give me that spine tingling sensation of a concert level audio system. They were kind of like a beautiful high maintenance woman, pretty to look at and fun to be out with but lacking authenticity. OK, maybe not the best analogy () but for me it came down to function over form. Not everyone wants this and it certainly can be damaging to your hearing if you're not careful, but I found what I was looking for in a HT sound system and can never go back to polite and pretty.


Great post. my one major problem with the speaker forum, and speaker reviews in general, is it assumes all of us listen to Diana Krall while sitting in a chair, sipping a martini. A good deal of us prefer Metallica or Nirvana, and as such simply aren't happy with 88DB sensitive speakers.

I can appreciate a great sounding Jazz recording as much as anyone, but that is not typically what I listen too. Typically, I throw on some Soundgarden and crank it to 11.
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post #222 of 824 Old 02-17-2012, 10:42 AM
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Originally Posted by RMK! View Post

You may want to mosey on up to Music Lovers in SF and get a demo of the Salon2's. When properly setup, they are amazing speakers for music (probably the best I have heard). Listening to well recorded Jazz with a smokey voiced singer is a very nice experience. My Studio2/Voice2 LCR's were great loudspeakers and the cabinets were furniture grade so they look good in just about any shared space environment.

What these audiophile speakers lack is the ability to play movies and concerts at realistic levels. The train wreck scene in Super 8 is a good example as is Metalica playing Sandman or Iron Man (with Ozzie) at the the Rock&Roll Hall of Fame Concert Bluray. I was disappointed that my beautiful Revels could not give me that spine tingling sensation of a concert level audio system. They were kind of like a beautiful high maintenance woman, pretty to look at and fun to be out with but lacking authenticity. OK, maybe not the best analogy () but for me it came down to function over form. Not everyone wants this and it certainly can be damaging to your hearing if you're not careful, but I found what I was looking for in a HT sound system and can never go back to polite and pretty.

Doubt if those Revels go low enough to do movie LFEs any justice without some help, a good sub is needed. Some speakers that do okay with classical or jazz just don't have what it takes for a good rock show either.

I haven't been by Music Lovers, tho have read about them, might just do that to see what 20k/pr plus buys (altho when I first googled these speakers I got an article indicating 35k...what does a pair actually sell for?).

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post #223 of 824 Old 02-17-2012, 11:02 AM
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Originally Posted by lovinthehd View Post

Doubt if those Revels go low enough to do movie LFEs any justice without some help, a good sub is needed. Some speakers that do okay with classical or jazz just don't have what it takes for a good rock show either.

I haven't been by Music Lovers, tho have read about them, might just do that to see what 20k/pr plus buys (altho when I first googled these speakers I got an article indicating 35k...what does a pair actually sell for?).

They are pricey (like $22K pair list) but you don't have to look very hard to find them for much less. As to are they worth the price? well, that is dependent on your priorities and discretionary funds. I will say they sound fantastic and give incredible detail to well recorded music.

These are not HT speakers although some use them for this purpose. Of course a sub(s) is necessary for good to great Home Theater sound.

The demo is interesting but be prepared for a bit of "attitude" from the sales staff...

To the OP, sorry for the OT ... Interesting Thread

HToM

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Originally Posted by mrcoop View Post

...this is the perfect start for someone looking to get into high sensitive speakers for ht or even music listening...

Thanks!

To be fair, many of the the active speakers will do a great job, or an even better job, due to their active crossover and perfect marrying to amps.

Also, passive speakers with enough power handling will work well too.

You do even have to investigate the high-sensitivity speakers a bunch, too. Be suspicious of a 5" or 6" driver that can supposedly hit 115db. That's why you see the 8" - 15" woofers even on speakers intended to play with a sub.

I probably should change the thread title to not say "high sensitivity," as I'm including active speakers, and those with high power handling.
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Originally Posted by nizl View Post

First, there is a well-known loophole in sensitivity ratings that is causing this spreadsheet to make it appear that Pro-series speakers have higher sensitivity than home speakers. They don't. Pro speakers run at 4 ohms, whereas home speakers typically run at 8 ohms. Manufacturers exploit this in measuring sensitivity:

http://www.diyaudio.com/wiki/Loudnes...er_Sensitivity

I appreciate this. I think I stated somewhere above that I was unsure about the sensitivity at 4ohm. Sometimes I felt like the manufacturer was compensating for that, and sometimes not. I'll read up more about this, and in the meantime, I dropped all the passive 4ohm speakers' sensitivity down by 3dB.

I'll have to check each of those speakers specs again to examine how sensitivity is qualified at what ohms. For instance, I think some of the speakers may have the sensitivity compensated for 8ohms.

But it sounds like if they just give sensitivity as XXdB anechoic 1m 2.83v for a 4ohm speaker, I should just drop its sensitivity by 3dB? How about if it's given for a 4ohm speaker but with 1 watt? (I haven't read your links yet, but I will).

This also would knock these speakers off the list:
SVSound MTS-02
PMC IB2S
Triad InRoom LCR Gold
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Originally Posted by Eyleron View Post

But it sounds like if they just give sensitivity as XXdB anechoic 1m 2.83v for a 4ohm speaker, I should just drop its sensitivity by 3dB? How about if it's given for a 4ohm speaker but with 1 watt? (I haven't read your links yet, but I will).

That would be the most accurate thing to do. You can see an example from JBL's docs that they have the false bump, and should be adjusted -3db:

http://www.jblpro.com/catalog/genera...x?PId=83&MId=1

Nominal Impedance: 4 Ohms
Sensitivity: 104dB, 2.83V @ 1m (3.3ft)

So that's more equivalent to 101 dB in reality.

Also, as to the other point I mentioned about wattage, you can adjust it easily and still get value from it in the spreadsheet. Simply calculate the metric as watts * ohms. For example:

Klipsch KLF-30: 400w * 8 ohms = 3200
JBL 4722N: 800w * 4 ohms = 3200

So those speakers would be very close in terms of current draw in real-world performance. If you want 3200 to mean something, take the square root and you get volts, so 56.56 V.

Normalizing for impedance is important, or else it's an apples-to-oranges comparison as it stands.
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Originally Posted by nizl View Post

Also, as to the other point I mentioned about wattage, you can adjust it easily and still get value from it in the spreadsheet. Simply calculate the metric as watts * ohms. For example:

Klipsch KLF-30: 400w * 8 ohms = 3200
JBL 4722N: 800w * 4 ohms = 3200

So those speakers would be very close in terms of current draw in real-world performance. If you want 3200 to mean something, take the square root and you get volts, so 56.56 V.

Normalizing for impedance is important, or else it's an apples-to-oranges comparison as it stands.

I'm confused. I can see how the voltage draw would be different between two speakers where you drive with the same wattage but have different impedances.
But, using the SPL calculations, shouldn't we get 3dB more SPL output from the JBL if we feed it twice the watts? I haven't seen those calculations use voltage, just watts.
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Originally Posted by Eyleron View Post

I'm confused. I can see how the voltage draw would be different between two speakers where you drive with the same wattage but have different impedances.
But, using the SPL calculations, shouldn't we get 3dB more SPL output from the JBL if we feed it twice the watts? I haven't seen those calculations use voltage, just watts.

Ohm's law calculator
http://www.ohmslawcalculator.com/ohm...calculator.php

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Originally Posted by lovinthehd View Post

Ohm's law calculator
http://www.ohmslawcalculator.com/ohm...calculator.php

Right, but how do ohms come into play here: http://myhometheater.homestead.com/splcalculator.html ?
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Originally Posted by Eyleron View Post

Right, but how do ohms come into play here: http://myhometheater.homestead.com/splcalculator.html ?

Use the ohm calculator to adjust between 8 and 4 ohm...you'll see the adjustment you need to make for power in your calculator for the equivalent situation...

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I owned a few high sensitive speakers and I can say this, the specs are a starting point. I owned Klipsch THX ultra 2 KL-650's, sensitivity 97 dB's, JTR triple 8's, sensitivity 97 dB's, MK S-5000's, sensitivity 92 dB's, JBL pro 104 sensitivity, eD cinema 12 sensitivity of 100 dB's, BFM DR-200's sensitivity of 104 dB's etc... In real life the Klipsch and MK's were about the same, the triple 8's were about 5 dB's more than them, the JBL's were 5 more than the JTR's(originals). The eD cinema's were 7-8 dB's more than the MK and the DR's were 5 more than the eD's. In sensitivity, that makes the list
1. Dr-200's at 105 dB's
2. JBL pro at 102 dB's
3. eD Cinema 12 upgraded 100 dB's
4. JTR 888's 97 dB's newer ones 99dB's
5. It does not matter anymore!
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Originally Posted by lovinthehd View Post

Use the ohm calculator to adjust between 8 and 4 ohm...you'll see the adjustment you need to make for power in your calculator for the equivalent situation...

Yes, I see the current is 7 amps or 14 amps. That tells me how the amp will behave.

My question still stands. "How does this relate to SPL output calculations?" I'm new at this. Please help me to understand.

In other words, given two speakers, same sensitivity, one rated at 4 nominal ohms, the other 8 nominal ohms, both rated for 400w, tell me how to use the ohms, volts, or amps in the SPL calculations to come up with a different result for the SPL output?

Otherwise, I'm going to feed 400w into the function and come up with the same dB SPL.
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post #233 of 824 Old 02-18-2012, 07:30 AM - Thread Starter
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Originally Posted by MKtheater View Post

I owned a few high sensitive speakers and I can say this, the specs are a starting point.

Especially since the sensitivities as calculated or tested vary in method.
Some are 50-500hz. Others are one frequency at 1000hz. Others are a much fuller range.

A speaker that was spec'd at 102dB but you feel gives out in the high freqs at high output, could've been spec'd at 1kHz, and if they'd judged sensitivity throughout its full operating range, they'd have had to say it was a 99dB speaker, if their highs roll off.

If we had a chart of consistently-performed lab tests including:
  • RMS power handling (distortion <= 5%)
  • Peak power handling (distortion <=10% 200ms burst of standard waveform, 800ms off)
  • Sensitivity measured over entire handled freq range (adjusted for 8ohm, anechoic, 1m, 1 speaker )
  • A calculation of how smooth the directivity is.
  • Frequency response @ +/- 3dB and +/- 1dB
  • In addition to nominal impedance, minimal impedance @ what Hz

You could then much more accurately sort and judge an apples-to-apples performance.

And certain graphs for better human judgement of performance, it'd be much more useful.

One of the problems is that the lab reviews, even distortion tests, seem to only use continuous input, not burst tests.

Heck, even the less formal listening tests often don't include pushing the speaker at reference level.

We need more standardized testing, like what's being done with subwoofers. I know it's a lot more difficult than with subs, as we're dealing with often passive speakers (subs usually include the amp), with factors like directivity, sensitivity, less tolerance for distortion, much more granular timbre qualities, etc.

Still, I expect a competent reviewer with lab equipment to tell me how this speaker performs with respect to its stated capability limits. I realize they can't always test the speaker to destruction like the manufacturer should be doing (among other things). But give me a few numbers at where distortion rises, at least! Assuming the speaker is said to be able to hit reference levels from some distance, then test that! Not, "The speaker reached 95dB when fed a test signal from one foot away."
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thanks Eyleron
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post #235 of 824 Old 02-18-2012, 08:13 AM
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Quote:
Originally Posted by Eyleron View Post

In other words, given two speakers, same sensitivity, one rated at 4 nominal ohms, the other 8 nominal ohms, both rated for 400w, tell me how to use the ohms, volts, or amps in the SPL calculations to come up with a different result for the SPL output?

Otherwise, I'm going to feed 400w into the function and come up with the same dB SPL.

Well, in this case you definitely would not get the same number, because the impedance is different. The impedance is the critical number in understanding wattage ratings for amps. 400w @ 4ohm is 1/2 the power as 400w @ 8ohm.

The link I previously posted was as straightforward an explanation as I've seen: http://www.gcaudio.com/resources/howtos/spkramp.html

What's confusing is it seems "backwards" at first. How can 400w be less loud than 300w?? The answer is because the wattage is a derived calculation. The voltage is what drives the calculations. The reason why amplifiers are specified in watts is because you DO have to know what impedance (ohms) you're targeting. But it can be confusing to understand when you look at speakers/amplifiers that 800w @ 4ohm will be less loud than 600w @ 8ohm.

Revisiting you sensitivity question:
Quote:


But, using the SPL calculations, shouldn't we get 3dB more SPL output from the JBL if we feed it twice the watts?

I understand your reasoning here, but in reality power supplies become a limiting factor. From http://www.a-vdesignstudio.com/infor...ng-home-stereo

Quote:


Another factor to consider when matching speakers with amplifiers is the load the speaker presents to the amplifier. Part of this is the impedance rating... You do need to be a little wary of the sensitivity rating of a 4 ohm speaker. 2.83V into an 8 ohm load is 1W. Manufacturers of 4 ohm speakers usually rate their speakers by that same 2.83V. However in a 4 ohm speaker there is half the resistance to current flow, meaning that, per Ohm's law, you are actually delivering 2W of power to the speaker. Some high end amplifiers are capable of delivering twice their current into the 4 ohm load but most are not.

As an example, look at Outlaw Audio's specs (they pride themselves on accurate ratings): http://outlawaudio.com/products/7700.html

200 watts RMS x 7 @ 8 ohms
300 watts RMS x 7 @ 4 ohms

So the amp would actually put out quite a bit less power if you were using it to drive the JBL 4722N vs the Klipsch KLF-30. In your theater, the JBL's would be noticeably quieter (or the amp would clip).

Anyway, as MKtheater pointed out, sensitivity is a starting point. And as you noted, it's easy to manipulate sensitivity by choosing what frequency to measure it at. Personally, I would subtract 3dB from the 4ohm speakers, figure a margin of error for all speakers of +/- 2-3dB or so, and call it a day.
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post #236 of 824 Old 02-18-2012, 09:16 AM - Thread Starter
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Originally Posted by nizl View Post

Well, in this case you definitely would not get the same number, because the impedance is different. The impedance is the critical number in understanding wattage ratings for amps. 400w @ 4ohm is 1/2 the power as 400w @ 8ohm.

I don't think we're caring about the wattage ratings for amps, though? I'm trying to determine the needed watts to hit a certain dB level using a speaker's ohms, sensitivity (now normalized for 8ohms, and power handling specs.

Let me re-phrase or qualify it a bit more:
"In other words, given two speakers, same sensitivity after normalizing for 8ohm, one rated at 4 nominal ohms, the other 8 nominal ohms, both rated for 400w, tell me how to use the ohms, volts, or amps in the SPL calculations to come up with a different result for the SPL output?

Otherwise, I'm going to feed 400w into the function and come up with the same dB SPL."

So, after I took your advice and dropped the sensitivity of the 4ohm speakers by 3dB, and thus the dB output of all those speakers dropped accordingly by 3dB, have I not already taken into account the difference of their stated impedance (8 vs 4)? If this is taken care of, then my output calculations should be fine.

Let's use the SPL calculator here.
12 feet anechoic; 400 watts of power
Speaker A:
  • 100dB @ 2.83v 4ohms; 400w peak handling
  • Normalize for 8ohms to compare apples and apples: 97dB
  • 111.8dB when fed 400w

Speaker B:
  • 97dB @ 2.83v 8ohms; 400w peak handling
  • 111.8dB when fed 400w


Quote:
Originally Posted by nizl View Post

I understand your reasoning here, but in reality power supplies become a limiting factor.

I don't see how that's relevant here, though. I'm not assuming any size amplifier. Or, I'm assuming an infinitely capable amplifier, where the only limiting factor is the speaker, because I'm comparing speakers.
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Quote:
Originally Posted by Eyleron View Post

Yes, I see the current is 7 amps or 14 amps. That tells me how the amp will behave.

My question still stands. "How does this relate to SPL output calculations?" I'm new at this. Please help me to understand.

In other words, given two speakers, same sensitivity, one rated at 4 nominal ohms, the other 8 nominal ohms, both rated for 400w, tell me how to use the ohms, volts, or amps in the SPL calculations to come up with a different result for the SPL output?

Otherwise, I'm going to feed 400w into the function and come up with the same dB SPL.

I just meant to adjust for the impedance in the first calculator so you can see that when you change from 8 ohms to 4 ohms your wattage doubles.

Keep in mind the nominal sensitivity rating is 2.83V at 8 ohms, using the calculator that gives you 1 W; when you change that to 4 ohms, you now get 2 W. Therefore, when you use your SPL calculator for a 4 ohm speaker you need to double the wattage...the SPL calculator should specify the sensitivity is 2.83V at 8ohm at one meter...that help?

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post #238 of 824 Old 02-18-2012, 04:28 PM - Thread Starter
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I got that from nizl's post, and I compensated sensitivity. It was the second part of what he was saying where I didn't see how it relates to spl output.
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post #239 of 824 Old 02-18-2012, 06:20 PM
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Quote:
Originally Posted by Eyleron View Post

Let's use the SPL calculator here.

Several of the calculators on that site are very valuable, but that particular one omits ohms, which renders it useless for your purposes. That calculator assumes 8 ohms, so it's not applicable to 4 ohm, or 2 ohm, or 6 ohm speakers.

It's clear you're still not grasping the fundamentals of watts/amps/ohms, which is ok. I think this will help. Open up this calculator: http://www.onlineconversion.com/ohms_law.htm

Do this:

1) Enter "8" for Resistance (ohms), "400" for Power (watts) and click "Calculate"
2) You should see: 56.56 Volts and 7.07 Amps appear in the other two boxes
3) Delete the values in the Power, Current, and Resistance boxes, leaving only 56.56 Volts.
4) Change the "8" to "4" for the Resistance box and click "Calculate"
5) You should see: 14.14 Amps and 800w appear

I've attached two screenshots of what you should see. See how halving the resistance requires doubling the wattage for the same output?

Bottom line: you need DOUBLE the wattage for a 4 ohm speaker, vs an 8 ohm speaker, to achieve the SAME loudness. So 400w @ 8 ohm = 800w @ 4 ohm. They will sound identical in loudness.

This is why the spreadsheet needs to normalize for ohms. It is a completely separate issue from the sensitivity trick.

More info: http://www.activebass.com/articles/item.asp?i=42

Quote:
Originally Posted by Eyleron View Post

Quote:
Originally Posted by nizl View Post

I understand your reasoning here, but in reality power supplies become a limiting factor.

I don't see how that's relevant here, though. I'm not assuming any size amplifier. Or, I'm assuming an infinitely capable amplifier, where the only limiting factor is the speaker, because I'm comparing speakers.

I understand where you're coming from, and for the purposes of the spreadsheet, you can ignore my comments. But people reading this thread need to realize that getting a 4 ohm speaker has downsides in requiring a significantly more powerful Pro-quality amp to achieve the same loudness they would expect from a "normal" (8 ohm) home speaker.

More reading: http://forums.audioholics.com/forums/828628-post1.html
LL
LL
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post #240 of 824 Old 02-18-2012, 07:56 PM - Thread Starter
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Quote:
Originally Posted by nizl View Post

Several of the calculators on that site are very valuable, but that particular one omits ohms, which renders it useless for your purposes. That calculator assumes 8 ohms, so it's not applicable to 4 ohm, or 2 ohm, or 6 ohm speakers.
...
Bottom line: you need DOUBLE the wattage for a 4 ohm speaker, vs an 8 ohm speaker, to achieve the SAME loudness. So 400w @ 8 ohm = 800w @ 4 ohm. They will sound identical in loudness.

This is why the spreadsheet needs to normalize for ohms. It is a completely separate issue from the sensitivity trick.

More info: http://www.activebass.com/articles/item.asp?i=42

OK, it's another issue. I'll need to read more to understand this.

It sure would help if the articles and calculators actually mentioned decibels, db, or spl. It appears they're talking about ohms law and how those variables relate in the amp, but not how it relates to spl output.

Thanks again for the info, and thanks for your patience!
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