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


I'd be interested in everyone's thoughts, but hopefully Sean will chime in...

Some reading I've been doing & the "is 22 watts enough" discussion has raised a question in my mind. I'll use the Linkwitz Orions as the example, but the real questions will (should?) apply to powering most any driver.

I've been reading Linkwitz's site on the Orions, some of the theory, what it takes to build them, suggested power..etc...and I remember some post that I read in the A-gon or AA archives stating that the 60 watts Siegfred suggests isn't enough to give significant bass. I read on the SL site that he likes the 60 watts as the amp will clip just before the speaker can reach full excursion & thereby the driver will not sustain damage. He continues to state that the higher power amp he suggests (a larger ATI) will result in the driver reaching full excursion prior to the amp bottoming out & thus driver damage may result.

>Proponents of "lower is plenty" might be, at least conceptually, in line with the needed power to reach a driver's maximum excursion (almost by defintion) being all the power necessary.

>Then comes the "more power, preferrably gobs more clean power" crowd that says more power is the best in most applications.

So my question(s):

>Is the difference between these two camps just "time"(instantaneous versus continuous power)? i.e Lots of mostly unused power sitting "idle" as a reserve for the couple millisecond demand of those dynamic peaks?

>From what I've read the SL Orions do very, to exceptionally, well on bass even with the 60 watts. How would 200 watts instead of his 60 improve the bass if the drivers bottom out at a little over 60 watts? Is it again just the millisecond peak demand for power that would be available or is there another reason?
fishboat

Showing 1 response by twl

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.