Does impedance matter?


In all my post readings, the #1 question category is the 'Does It Match' question. This is usually addressed as a speaker / amp question.
Most responders start with impedance.
Of all the things to look for in a speaker impedance is down the list. I have looked at at many speakers measured by reputable testers. 8ohm 'nominal'? These guys are all over the place from 3ohm in mid frequencies to 20 ohms+ at resonance. Some are 4 or 5 ohms from 200hz to 1khz...prime musical turf.
Is it easy to drive? Well, it's an 8 ohm speaker, so it should be. Not so fast, there. This is only part of the story.
Please check out this link::http://www.hometheaterhifi.com/technical-articles/228-a-secrets-technical-article.html?start=1

The Smith Chart is a fine way to visualize the quality of load a speaker may actually represent.

When looking at a speaker then, it is important in evaluating the load it represents by not only the impedance, but the inductance and capacitance as well. As voltage leads or lags current, the strain goes back to the amp.
Please see this link for an explanation / details.
http://sound.westhost.com/patd.htm

Just watching Diana Krall in Paris on the TIVO.

magfan
Shadorne, while it is true that powered speakers have many advantages, they do not sell for one simple reason, most audiophiles want the capability of altering the sound of their system. This may be good or bad, but it is the simple truth. I was an Audio Pro dealer in the 80s, they made a powered speaker, the 4-14 I think, that was far ahead of it's time. I think I sold 2 pairs. When I sold Meridian I didn't even try to sell the speakers. In fact, many, if not most audiophiles select the amp before the speaker. I will agree with you that this is totally bass akward but unfortunately true. I must also admit that I use passive myself although I choose my amp to compliment the speakers I am using not vice versa. Our systems are chosen to reproduce music the way we ourselves hear it and active speakers limit that to a significant degree. The full development of unobtrusive digital tone controls may be the best path to active; Meridian is working along these lines but I am not really currant with their work.
Stanwal,

You make excellent points and I am in complete agreement.

most audiophiles want the capability of altering the sound of their system. This may be good or bad, but it is the simple truth

This statement just about sums it up. However it presents another illogical paradox when confronted with the concept of EQ or tone control. Most purists shun these tools yet good or bad, they also seek the capability of altering the sound of their system. Go Figure. (And they used to say that you can never understand a woman....but hang on, most audiophiles are men!!!)
There is nothing confusing about audiophiles rejecting the use of equalizers or other tone benders. Are we not he leading example of, and may actually define, what being a masochist really means? :-)

Anyone want to buy my demo hair shirt?

Anyone want to buy my demo hair shirt?
Newbee (System | Reviews | Threads | Answers)

Only if it is a Tube Top. (sorry, couldn't resist) ;)
You said it Magfan! Speaker impedance should be studied/viewed uisng *both* the impedance & phase curves. The phase angle lets the user know what sort of real-time strain will be put on the amp.

If users do not like passive x-overs, they are free to try active x-overs. There are many examples in the market + many more from various speaker manuf.
If you choose to stick with passive x-overs, then, large L & C values are needed. Just the physics of the matter!
Boothroyd-Stuart Meridian's method for active speakers using digital technology is supposed to be the best-in-class tho' I have not heard any of their speakers.
ATC's method of active speakers is your other choice. Many people like their sound (implying they like their design & the sound of their in-built amps). Maybe you will like them too?