speaker excursion..."mo power"..and bass..Sean

Hey Sean,

Neither Eldartford nor I totally denied that L & C do lose power.
Eldarford: "Passive crossovers do not absorb power to the degree that you suggest." &
I wrote: "Inductors will dissipate some heat as a coil of wire will have some resistance. If one is using a low ESR capacitor, very little heat gets generated in a capacitor."

However, I think that you are mistaken as to just how much gets dissipated in these Ls & Cs on average.
Optimizing the losses in a reactive component is NOT the way biamping achieves its perceived increase in power. Separation of power amplification into multiple chassis & the constructive addition of the music signal is what gives biamping its perceived increase in power.

"The comments about the active crossovers increasing the gain of the signal have little to nothing to do with amplifier capacity."
True! However an amplified signal fed into an amp needs less amplification to the speaker => more headroom for dynamics. Such a setup would have more air/the music would flow easier/more transparent.
The comparison is between passive & active xover cases.

"Couple this with the fact that your .1 ohm output of the SS amplifier is typically fed into 40 - 120 ohm speaker cable"
What???? Who in their right mind would use a 40-120 Ohm speaker cable?? Does a speaker cable with 40-120 Ohms even exist? I think that you would ripe for catching much flack for this one, Sean! :-)
I think it's a typo. You really meant milli-Ohm, right??

"Reflected EMF is a reality that the amps have to deal with."
Oh, it certainly is. No question about & I never denied it in my post. However, not to the degree that you mentioned in your original post. There IS the reverse isolation of the xover & their IS the output impedance of the amplifier/damping factor as only an active circuit can get rid of the back-EMF

"Damping factor is a hoax and is completely taken out of context."
No it certainly is not! Without a damping factor, which is really a glorified name for amplifier output impedance there'd be no "out muscling" the woofer.
We can agree to disagree here, which is just fine w/ me.
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Anyway, I, too, am in the more power, the better camp as long as the user is careful to not overdrive the speaker. If there are transients, then they should be shorter in duration (than being longer) & if one doesn't know then it's better to listen with a slightly lower level to be conservative. Case-in-point: Last summer I fried my Green Mountain floor stander tweeter after trying to break-in the woofer by playing music too loud for 14 hrs at a stretch! What Roy Johnson told me was that tweeter can handle way more than its 100W RMS rating if I play loud music for about 3-4 minutes (1 track) every 20 minutes or so. He says that he does that all shows regularly & the tweeter survives each time. So, now I know.......
More power results in the music flowing better, more air, more transparency, more lower level details.
Drivers can handle many more watts of peak power even tho they are rated for lower RMS power. (Usually, the driver ratings are RMS power, which is average program power).
So, yes, Fishboat, its reserve power mostly.
Additionally, a large amp has more current capacity even at lower power levels, which what gives the music is ease of flow. To get that driver moving, you need current in the voice coil.

I think the damping factor issue is directly related to the speaker in question, which may very likely have a very low moving mass and very high magnetic field and very short excursion length(such as my speakers), and thus have a very significant amount of its own internal damping ability.

In cases such as this, high numerical "damping factors" may actually inhibit transient response, and may not be an advantage at all.

As long as the relationship between the amp's output impedance and the speaker's relative impedance at any given frequency(damping factor) remains enough to control the speaker(>5), then it is sufficient in that circumstance. It is when the speakers have poor internal damping characteristics(ie high moving mass/low magnetic field strength/very long excursion length) where problems are more likely to be "fixed" by high electrical damping factor numbers.

Regarding high power being "better" than low power, we all know I'm in the "low power" camp. I think(and I'm pretty sure Sean agrees) that you are much better off to have higher efficiency speakers than to try to overcome low efficiency speakers with brute force, because of the exponential curve of power needed to add a few db to the output.

Also, it has been my experience that high power amps seem to be less "delicate" in nuances and details, due to the beefy construction needed to handle all that power. And in addition, to have power like that, you simply have to go out of Class A operation, which I don't like to do.

And, when you have low efficiency speakers, you have a higher "low-level detail threshold" because it simply takes more power to make the speaker move at all, so that some very low level stuff never even makes it out of the speakers, unless you have it turned up alot.

If the speakers are high efficiency, you can still get pretty loud SPL, with great low level detail, with very low power amps. I do realize that this normally sacrifices some of the very low bass. I think it is not a bad trade-off.

I do realize that this (very low power amps -high efficiency spkrs) normally sacrifices some of the very low bass

As you note, "normally". You can add active subwoofs for very little outlay and resolve the issue (if issue there is).

Whoa!

This thread had a great technical edge and now its tumbling out of control.

Passive crossovers are "voltage dividers", this is where the power goes, to ground especially in 2nd order and filters with notch filter etc. There are small losses in the components but the passive filter itself is a loss as it is addressing the fully amplified signal.

Drew/Bombay & Sean your original long posts were about 75% correct but this second group is getting into the land of speculation. Again good posts but now you guys are down to about 50% correct.

Sorry,I don't have time to correct the errors point for point.

Cinematic_systems...In a passive crossover, power does indeed "go to ground", but it goes through the drivers, which is the whole point of the thing. The power "wasted" by notch filters is minimal, unless the drivers are truly aweful.

The 10 AWG air coil inductors in my MG1.6 have about the same resistance as the original iron core inductors. This is why most speakers use iron core inductors.

When estimating the broadband signal equivalent to two bandlimited signals, the usual approach is to do an RSS. For example...

100^2 + 60^2 = SIGNAL^2

SIGNAL = 117

If the two band limited signals are equal, the equivalent broadband signal is maximized at 1.41 times the band limited signal.

However this assumes that the two bandlimited signals are uncorrelated, and this is not typical of music, where loud low notes are often simultaneous with high frequency harmonics, not to mention cymbal clashes.

As to tweeters burning out...I guess that some may be huskier than others, but I just took out two SEAS Excel T25CF-002 Millenium tweeters with about a three second burst of noise due to an interconnect problem. And these tweeters were not driven directly from the amp, but rather through a passive crossover. However, replacement voice coils are available, and Madisound even installs them for free. This suggests to me that blown out voice coils must be quite common.