Shall we...? : A new measurement for speaker ratings and efficiency. "USE"

[dcastar]

First off... any mathematicians on the board? This may be your calling...

 

Carried over from another thread on this board...

 

With marketing departments posting impressive numbers that can hardly be believed... and with a lack of understanding of ratings from the consumers in the middle-market, now might be the time for us to develop a new rating to help the average consumer compare speakers on equal playing fields.

 

A perfect example of this: How many powered speakers out there are advertising 1000w amps? Pretty much all of them, right?? Your average consumer sees that and goes.. Wow ONE-THOUSAND WATTS -- OMG!!! While not having the basic knowledge or understanding that if the amp actually put that much power into the driver, it would likely blow. Beyond that, marketing folks are putting out nonsense frequency responses.... the old standard was +/- 3db.... now you see +/- 10db.... or a laughable +/- 6db.

 

What shall we ever do!?!

 

It's come time for a new performance metric to be developed... Think of this moment in-time as being much like the statistical evolution that took place ~10 years ago in sports statistic keeping. IE;"Moneyball" in MLB . Or in the NBA, John Hollinger's NBA metric, is called "PER" rating for rating a specific players efficiency. In fact, John Hollinger developed this metric on a message board, just like this one.... gathering input from others and perfecting it. Let's do this!!!

 

Our new performance metric for measuring powered and unpowered speakers; Brand it : Speaker's "Usable SPL and Efficiency" or simply 'USE'

 

USE should take into account:

"Max Continuous SPL in freespace @

"120v Amperage Draw @ Max Continuous SPL in freespace"

+/- 3db Frequency Response

 

Somehow work out the formula that a max possible score is 100.... and we have Bronze, Silver, Gold and Platinum certifications for ratings above 70,80,90, 95 respectively.

 

 

So... how about it...? What say you, pro audio folks!?

[agedhorse]

The problem is that each of those specs has major relevance to some users and little to others. Things like weight, power draw for example.

 

I know where you are coming from though and agree, it would be helpful if there were some general perfromance oriented metrics that could be incorporated into a single number... but every application is different. that's what makes it tough.

[Zeromus-X]

The biggest problem with this is that marketing sells so many speakers, no manufacturer would agree to adopt it. And unless it was universally adopted, it wouldn't be a meaningful number.

 

In the computer world we ran into this when Intel and AMD decided to deviate from the way they operated things. You have an Intel chip running at 1.4 GHz, and then an AMD chip rated at "1400+", which they took to mean "This chip performs as well or better than a 1.4 GHz chip", whereas it was only rated at 1.13 GHz. And for some applications that was true... but in the end the chip was still slower. Nowadays it's not as much of a concern because CPUs are fast enough that, to be honest, it doesn't make much of a difference anyway... fortunately.

[Bobby1Note]

 

With marketing departments posting impressive numbers that can hardly be believed... and with a lack of understanding of ratings from the consumers in the middle-market, now might be the time for us to develop a new rating to help the average consumer compare speakers on equal playing fields. A perfect example of this: How many powered speakers out there are advertising 1000w amps? Pretty much all of them, right?? Your average consumer sees that and goes.. Wow ONE-THOUSAND WATTS -- OMG!!! While not having the basic knowledge or understanding that if the amp actually put that much power into the driver, it would likely blow. Beyond that, marketing folks are putting out nonsense frequency responses.... the old standard was +/- 3db.... now you see +/- 10db.... or a laughable +/- 6db. What shall we ever do!?! It's come time for a new performance metric to be developed... Think of this moment in-time as being much like the statistical evolution that took place ~10 years ago in sports statistic keeping. IE;"Moneyball" in MLB . Or in the NBA, John Hollinger's NBA metric, is called "PER" rating for rating a specific players efficiency. In fact, John Hollinger developed this metric on a message board, just like this one.... gathering input from others and perfecting it. Let's do this!!! Our new performance metric for measuring powered and unpowered speakers; Brand it : Speaker's "Usable SPL and Efficiency" or simply 'USE' USE should take into account: "Max Continuous SPL in freespace @ "120v Amperage Draw @ Max Continuous SPL in freespace" +/- 3db Frequency Response Somehow work out the formula that a max possible score is 100.... and we have Bronze, Silver, Gold and Platinum certifications for ratings above 70,80,90, 95 respectively. So... how about it...? What say you, pro audio folks!?

 

 

I like the concept. Now, you just have to convince the marketing guys to take a step back, and be honest.

[agedhorse]

Now, you just have to convince the marketing guys to take a step back, and be honest.

 

Never going to happen, not culturally possible

[Bobby1Note]

Never going to happen, not culturally possible

 

You got that right. May be possible in Utopia.

[RoadRanger]

"No one in this world has ever lost money by underestimating the intelligence of the great masses of the plain people. Nor has anyone ever lost public office thereby." - H. L. Mencken

[HCRobe]

No reason why it couldn't be done independently, Consumer Reports style. Community supported, buy or volunteer equipment to be thrown on a test bed designed to be agnostic, fair and reproducible. Cheap and easy on the interwebs.

 

Toms hardware is another example.

[Bobby1Note]

 

No reason why it couldn't be done independently, Consumer Reports style. Community supported, buy or volunteer equipment to be thrown on a test bed designed to be agnostic, fair and reproducible. Cheap and easy on the interwebs. Toms hardware is another example.

 

 

Problem is, they'd have to acquire gear, test it, pay the tester, publish and distribute the test results, at their own expense. What's in it for them? We'd need a guy like Bennett Prescott running the show.

[agedhorse]

The bigger problem is that different parameters are either crital or not at all important depending on the application. Even basic power testing contains specific attributes of things like dynamics versus time perormance that can influence how an amp sounds (bigger or smaller) than the publiushed continuous power, and how they drive reactive loads (some amps have enormous headroom for driving reactive loads and some {censored} the bed). Is that stuff important to you? the average consumer? Me? (it is critical for SOME applications and not at all for others).

[dboomer]

There's an easy way to make this happen. Just convince some/any/all manufacturers that it would make an improvement to their sales numbers. Problem is ... it won't and it would increase your cost for the very speaker you own. How much more are you willing to pay for the speaker you already have just so you have a more relevant set of numbers (not an improvement, just a tally).

[dboomer]

We'd need a guy like Bennett Prescott running the show.

 

A marketer?

 

I'd rather have a scientist, but that hasn't worked very well in practice as the major societies can't agree on what to test for and how to conduct the test. So when you see a legitimate number ... like 500W ... it doesn't mean the same thing as it depends on who's method you used. And then even when you figure that out how could you possibly transfer that number to your usage which is different again.

[NUSound]

[Bobby1Note]

A marketer? I'd rather have a scientist,

 

True, he is now (North American sales manager for B&C), but he's a no-bull{censored} kinda guy who takes charge and gets things done,,,, and, he's a hoot to read. Doesn't he also write articles for a "live sound" magazine?

 

The magazine could reap some benefits by publishing standardized test-results (circulation/advertizing) but that can be a double-edged sword too.

 

AudioFanzine magazine, in Europe, seems to do a decent job, from the few tests I've read. They send the speakers out, to an independent sound-lab for analysis,,, no "in-house" testing.

[badhorsie777]

Curious to hear from you more experienced types - is there ANY benefit from over-speccing an amp in a powered cab? The hype machine claims it increases headroom, no chance of being underpowered, etc... I know in my live bass guitar rig I have an eden XLT cab that takes 350 watts, but I power it with a power amp rated at 1000 watts. The "word on the street" has always been that this allows a clearer, more punchy dynamic sound, and my subjective experience has been that it holds true, for my instrument.

 

That's why I was excited to see an overly powerful amp in the new Yamaha DXR speakers (and the QSC and the rest) - I know it might just be economy of scale, like they already had the amp modules for another speaker, so it's cheaper to plop it in the smaller cabs, etc. But my ears tell me that the combination of the high power, their DSP (multiband compressor, if I understand correctly that shifts depending on output volume), and the cabs themselves really do sound clearer than the lower-powered stuff. Clear at all volumes, too... How much of this is the power reservoir being available for those peak notes and how much is the rest of the design?

 

Thanks,

Matt

(satisfied owner of a teeny tiny new PA with a big sound)

[dcastar]

Curious to hear from you more experienced types - is there ANY benefit from over-speccing an amp in a powered cab? The hype machine claims it increases headroom, no chance of being underpowered, etc... I know in my live bass guitar rig I have an eden XLT cab that takes 350 watts, but I power it with a power amp rated at 1000 watts. The "word on the street" has always been that this allows a clearer, more punchy dynamic sound, and my subjective experience has been that it holds true, for my instrument. That's why I was excited to see an overly powerful amp in the new Yamaha DXR speakers (and the QSC and the rest) - I know it might just be economy of scale, like they already had the amp modules for another speaker, so it's cheaper to plop it in the smaller cabs, etc. But my ears tell me that the combination of the high power, their DSP (multiband compressor, if I understand correctly that shifts depending on output volume), and the cabs themselves really do sound clearer than the lower-powered stuff. Clear at all volumes, too... How much of this is the power reservoir being available for those peak notes and how much is the rest of the design?

 

True, it's always good to have headroom. With your bass cab, having it would likely give you the power/ability for a momentary slap/pop... but you take a risk of 'clipping' and overdriving your speakers.... much the same you would a PA speaker.... which ultimately over time, decreases the life of the speaker and leads to blown drivers etc.... The general rule of thumb we seem to mostly agree on is that a speaker should have an amp that has 1.5x the power available, relative to its continuous power rating. The whole "double your speaker wattage" mantra, was just another successful marketing campaign to get you to buy bigger amps. "Bigger is better, right??" *sigh*.

 

Anyhow, theoretical power of 1000w powered speakers and their real world useable power is another thing. There is a-LOT going on behind the scenes in their processing, eq, and limiting... and you'll be hard-pressed to find a 1000w marketed power speaker using anything more than 600 watts.

 

Here's a nugget to think about.... Taking into consideration a speaker with 97db of sensitivity vs a speaker with 100db... that means it will always take the 97db speaker TWICE the amount of power to achieve the same SPL level that the 100db speaker does. That's just physics... and will always hold true.

 

The WAS5000 --- the worlds loudest speaker, can produce 165db at 10000 watts. The basic math on that means its sensitivity is ~125db @ 1w/1m. So, 1 watt of power gives you 125db... 2 watts 128b.... if you put 8 watts of power into it.... it'll give you 134db of 'volume'.

Think about that... it can produce 134db at 8 watts. 134db is about the 'peak' volume of most current powered speakers on the market, and it takes them 500+ watts to produce it.

Mantra: It's not about how much wattage you have.... it's how efficiently your speakers actually use the wattage.

 

In reality, that's the main point here anyway. We're trying to devise a measurement of speaker quality with how efficiently it uses the power. I think that making the rating system as easy to understand for consumers, and giving the companies a "certification" they can market their speakers.... 2 birds, 1 stone.

[drumstix]

Wouldn't you also have to standardize and list the frequency tested? Like test a subs efficiency at 80hz. Or maybe even lower at 50hz.

[Zeromus-X]

That'd make it difficult for some subs to really stand out, too; the field is too wide. How do you have a standardized frequency when you've got subs like the Behringer which likely drop off around 60-80 Hz, and some of the L'Acoustics/Dave Rat stuff that seems to hit about 1 Hz @ -1dB? The scale would have to be weighted and that immediately throws confusion into the mix.

[agedhorse]

 

I know in my live bass guitar rig I have an eden XLT cab that takes 350 watts, but I power it with a power amp rated at 1000 watts. The "word on the street" has always been that this allows a clearer, more punchy dynamic sound, and my subjective experience has been that it holds true, for my instrument.

 

 

This is also the single leading cause of damage to bass guitar drivers in the industry. The problem with the premise is that headroom is only headroom if it's available only to prevent distorting of the signal. As soon as it's used, it's no longer headroom. I probably see more 10" drivers damaged by too much power, almost always mechanical damage from overexcursion. Another thing about the power rating of a bass cabinet, it may be 350 watts as 100Hz-2kHz but it's probably

[dcastar]

 

Wouldn't you also have to standardize and list the frequency tested? Like test a subs efficiency at 80hz. Or maybe even lower at 50hz.

 

 

Yes, this is definitely something that would need to be considered in the rating formula. It would be a certification for Tops and Subs....

Typing while thinking here:

For tops 50Hz-18kHz,

For subs 35Hz-100Hz

Any lower/higher extension gives bonus points, as long as it can maintain +/- 3db of variance, with less than 2.5% THD.

 

 

Also - another thing just dawned on me. The THX certification for home theatre speakers.

http://extranet.thx.com/products/home/speakers.html

This is basically the same idea being applied here. A set of standards applied to give a certain level of certification for speaker clarity, quality, and efficiency. You see quite a few manufacturers adopting this "test" and certification... and marketing it in their speaker products.

[badhorsie777]

My preamp (a Demeter) is never releasing enough signal into the poweramp to push its max into the cab... not to derail the discussion completely... Is there, then, ZERO benefit for a poweramp having more than it needs in reserve? Is it, in other words, more efficient/effective when it's pushing half of its wattage than its upper limit?

[Randyman]

If the goal is to have one spec that's meaningful and understandable, why not leave the marketing department their phony specs on wattage and just concentrate on having a standard way of measuring db spl, which is much more relevant than horsepower ratings anyway-

[agedhorse]

 

Also - another thing just dawned on me. The THX certification for home theatre speakers. http://extranet.thx.com/products/home/speakers.html This is basically the same idea being applied here. A set of standards applied to give a certain level of certification for speaker clarity, quality, and efficiency. You see quite a few manufacturers adopting this "test" and certification... and marketing it in their speaker products.

 

 

THX is essentially nothing more than a marketing organization in actuallity.

[agedhorse]

 

not to derail the discussion completely... Is there, then, ZERO benefit for a poweramp having more than it needs in reserve? Is it, in other words, more efficient/effective when it's pushing half of its wattage than its upper limit?

 

 

Under these conditions, there is zero benefit.

[dcastar]

 

THX is essentially nothing more than a marketing organization in actuallity.

 

 

Maybe THAT's the trick then. We form an audio marketing agency and revolutionize the marketplace. Lol.