Relative power into woofers and tweeters?

To be frank, I'm not at all surprised by the result of the experiment.
so we go back to the question.. i don't know how manufacturer's rate their shit.. is it based on the 1 second max power? is it based on the crossover in place? is it based on the raw rated power formulated calculation to the theoretical crossover frequency or what? .. that's what i meant by i don't know.. and it doesn't seem to make much sense.. so going back to OP's question... what's the answer?
 
what's the answer?

The answer is, there is no one answer unless the manufacturer has defined the rating method per an IEC or maybe EIA test method.

We know for sure that your "100W" tweeter cannot handle 100W continuous power, or not even 60W continuous power. Thus, logical to conclude its 100W rating is intended to imply the tweeter is suitable for use in a 100W speaker system. And, based on the distributions shown in the chart, reasonably is expected to handle just a small fraction (10-15%) of the total power, on a music-type duty cycle, not continuous.

All one has to do is look at the tiny wire and small area of the tweeter voice coil re. heat dissipation to understand the continuous power handling capability must be small indeed.
 
The answer is, there is no one answer unless the manufacturer has defined the rating method per an IEC or maybe EIA test method.

We know for sure that your "100W" tweeter cannot handle 100W continuous power, or not even 60W continuous power. Thus, logical to conclude its 100W rating is intended to imply the tweeter is suitable for use in a 100W speaker system. And, based on the distributions shown in the chart, reasonably is expected to handle just a small fraction (10-15%) of the total power, on a music-type duty cycle, not continuous.

All one has to do is look at the tiny wire and small area of the tweeter voice coil to understand the continuous power handling capability must be small indeed.
many speakers are rated as continuous at rates that isn't much below the RMS definitely not half .. so that suggests most of the ratings are bullshit ...
 
many speakers are rated as continuous at rates that isn't much below the RMS definitely not half .. so that suggests most of the ratings are bullshit ...

That's sorta the point. Unless there is a defined test method specified by the mfg, as IEC 268-5 used by JBL in their pro audio stuff, you don't know for sure what it means.

That said, common sense should suggest that hair thin (or thinner) wire cannot handle very much continuous power.
 
That's sorta the point. Unless there is a defined test method specified by the mfg, as IEC 268-5 used by JBL in their pro audio stuff, you don't know for sure what it means.

That said, common sense should suggest that hair thin (or thinner) wire cannot handle very much continuous power.
yeah..comply and claim.. that is why vintage stuff has honest ratings whilst recent stuff is bullocks "mostly"
 
yeah..comply and claim.. that is why vintage stuff has honest ratings whilst recent stuff is bullocks "mostly"

Misleading claims back in "the good old day" are why the FTC stepped in to attempt to put some order to things like amplifier ratings.

So, if you think generous, misleading, or outright bullshit claims are something limited to newer stuff that's simply incorrect.
 
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Remember, friends, that most tweeter damage comes from an insufficient amplifier overdriven into distortion. In all my years of audio repair I have never seen a tweeter in a system with a properly designed and functioning crossover being zapped by too much power. I have seen that happen in homemade systems with poorly matched drivers and an inadequate crossover.

Basically, in most commercial designs, the tweeter gets, at most 20% and more likely 10-15% of available power through the crossover. Again, though, as one member has already stated, it is highly frequency dependent and it is highly unlikely that you'll get a treble frequency with the energy of a bass tone or a modern amp that can deliver it for more than the briefest period of time.
 
Looks like I wandered off too early from this thread!

As for the changes introduced by more tweeters - impedance, crossover, etc. - I'm well aware and will account for that. For the curious, here's the design thread for the No Stinking Badges Risen From the Dead Line Arrays. I'll warn you it's a lot of me thinking out loud, and no sawdust has been made, yet, but the design is almost there.

http://audiokarma.org/forums/index.php?threads/nsb-line-array-project.764445/
 
Misleading claims back in "the good old day" are why the FTC stepped in to attempt to put some order to things like amplifier ratings.

So, if you think generous, misleading, or outright bullshit claims are something limited to newer stuff that's simply incorrect.
sure.. but some brands had the honesty and reliability.. i dont know when exactly but probably everyone began going spec bullshitting in early 80ies..
almost every marantz amp made in 70ies produces more power than what they were rated for by current standards..

setting norms for ratings don't stop manufacturers from lying.. then they make something to beat that measure standards just pass the test, but not actually perform what is claimed..
 
sure.. but some brands had the honesty and reliability.. i dont know when exactly but probably everyone began going spec bullshitting in early 80ies..
almost every marantz amp made in 70ies produces more power than what they were rated for by current standards..

setting norms for ratings don't stop manufacturers from lying.. then they make something to beat that measure standards just pass the test, but not actually perform what is claimed..

Nonsense.

Grind your axe, whatever that may be, elsewhere.
 
Nonsense.

Grind your axe, whatever that may be, elsewhere.
if it were nonense.. would you care to explain why i have observed "significant" variations of performance and power provided by "hundreds" of gear i bought and sold over the years?
these weren't home made gear from the ghetto..
 
if it were nonense.. would you care to explain why i have observed "significant" variations of performance and power provided by "hundreds" of gear i bought and sold over the years?
these weren't home made gear from the ghetto..

If you want to converse about something specific, I'm game. But, if all you're going to do is whinge about the injustices of specifications I'm not interested.
 
If you want to converse about something specific, I'm game. But, if all you're going to do is whinge about the injustices of specifications I'm not interested.
all i am saying is setting a standard does not make manufacturer's honest and does not make gear comply with true quality musical reproduction..
an electrical measure at x frequency at y conditions does not mean that amp can reproduce quality music where million frequencies pop around by second. where you cannot set a rule to standardise or measure such broad situation. so set the norms .. fine, i'm not against it, but at the end of the day gear still varies, and user feedback and experience is still what matters to me.. i trust some brands ratings, i don't trust some others..
i used to be a spec person, just read the specs and say ok this is good .. then i met with vintage marantz gear with 20-30 watt ratings 1% thd and they sounded tons better than my super duper 0.0005 thd, 120watt 110db amps.. which changed everything..
i don't even bother reading specs anymore really... i currently have about 6 multi channel amps in stock, all within from last decade, all rated 120 -170wpc all were over around 2000 bucks or more when new and all sound like crap...
 
Perhaps there is more to sound quality than wattage, or even THD. Are they lying, or is it just that the typical reported specs don't tell the whole story?

@whoareu99: Extra points for 'whinge'. :thumbsup::rflmao:
 
Perhaps there is more to sound quality than wattage, or even THD. Are they lying, or is it just that the typical reported specs don't tell the whole story?

@whoareu99: Extra points for 'whinge'. :thumbsup::rflmao:
precisely..
what overall sound quality is from an amp is far from blah blah rating at blah blah measurement... i've seen amps rated 20 watts but hold a grip on the woofer and drive it tight no matter what volume, and i've seen amps sound like a child beating on a flat balloon and were supposed to be good stuff.. so when it comes to standardising something that cannot be standardised we go in a situation of HUH...
i just serviced a 2220b and it makes most modern stuff sound like a joke.. is thd something we can really hear? at what %? how do they rate over all distortion where every frequency sounds so ****ed and wrong but somehow they claim no distortion? some of these older stuff were supposed to have really low dampening factors that supposedly matters a lot.. but my ears tell me the opposite.. so i don't know honestly.. all i've learnt over the years was to hold little respect to specs... and more regards to reliable feedback.. and above all.. self test . self observe...

just as an example.. look at the specs of pioneer a400 and and pioneer 400x.. same circuit. i think same or similar specs... one is a champ the latter is a shithole.. as they cut down costs on parts quality.. in theory electronically it wouldn't matter a 10 uf cap is a 10 uf cap right.... well sonically .. it does
and i did test this.. i bought a 400x tested it .. awful.. assuming i got a bad copy i bought another near mint condition. same results... transformer hum.. frequencies all sound wrong and all over the place.. yada yada...
 
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Correction on my speaker project specs: just noticed that the NSB woofer is 10 MAX, but 5W RMS. So the power handling of the woofer array is actually half what I thought, 16x5= 80W. The tweeter array is still 9x2W = 18W (double checked that to be sure). So my ratio is now about 4.5. Much less of a discrepancy than I feared.
 
Correction on my speaker project specs: just noticed that the NSB woofer is 10 MAX, but 5W RMS. So the power handling of the woofer array is actually half what I thought, 16x5= 80W. The tweeter array is still 9x2W = 18W (double checked that to be sure). So my ratio is now about 4.5. Much less of a discrepancy than I feared.
i found some useful info and a chart in this thread might be of some use to you https://www.avforums.com/threads/how-to-calculate-w-rms-on-3way-speaker.1935568/
 
Good stuff Glen, thanks.

I started trying to figure out the db output (sensitivity) and it gets confusing fast with the series and parallel and coherent sources and so on. That thread has a link to a calculator though...
 
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Finally got line array SPL calculations sorted out by doing some reading. Found a great calculator spreadsheet in this thread:

http://www.htguide.com/forum/showthread.php?27677-Calculating-line-array-sensitivity

I'll post the Excel file somewhere more find-able on AK. I'm getting the same results from this spreadsheet as I do from hand calculations so it's working correctly.

So now I think my problem isn't impedance or relative power handling between woofer and tweeter arrays, but relative sensitivity.

My array of 16 woofers at 87 db/1w/1m (each) should give a combined sensitivity of 99 db. These would be wired in 4x4 series/parallel for an overall 8 ohms nominal impedance.

The tiny 1/2" inverted dome tweeters are only 66 db each though. An array of 16 of them (again in 4x4 series-parallel to maintain 8 ohms)comes to 78 db. This is 21 db lower than the woofer array so I'm worried about relative output. The rule of thumb for driver selection is to get the SPL ratings close, so I thought. Tweeters can be padded down easily but woofers not so much - at least it's not typically done.

I can manipulate the number of tweeters (15-20) and the wiring to get SPL up to 80 db with tweeter array impedances of 4 to 6 ohms. Not much help there.

Almost seems like I need to use a crap ton more of these little tweeters. Admittedly even 16 of them, with 1/8" between mounting holes, only makes a 14" tall array, whereas the 4" woofer array is over 5 feet. So the tweeters really aren't much of a line array. Unfortunately the darn things are $2.50 each which is running up the cost of this super cheap line array. I think it's still cheaper per inch than ribbon tweeters (there is a nice Dayton that's 4" or 6" tall and $30+.

I'll do some more calculations for larger tweeter arrays. I may have to bite the bullet.

Thoughts anybody?
 
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The other way is to just make it a bi-ampable speaker with active external crossover so that different volume settings can be used for the two arrays. Kinda hate to do that - I have the gear for it myself but it limits the usability for anyone else.
 
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