Choosing Drivers for a Speaker

solacedagony · Post by **solacedagony** » Wed Apr 19, 2006 10:36 am

How would you decide if two speakers would work well together (referring more to a mid+tweeter 2way setup)? By looking at response graphs and making sure their capable response overlap and decide the crossover point from that? Or by other measurements? Anyones thoughts on this?

Robert Wollenberg · Post by **Robert Wollenberg** » Wed Apr 19, 2006 10:48 am

I've been looking at their response graphs and also speaker sensitivity.

solacedagony · Post by **solacedagony** » Wed Apr 19, 2006 12:10 pm

Well, speaker sensitivity I believe you can adjust using resistors in your crossover. That's why I didn't consider that a big deal. Or does it matter more than I think?

_gonz_ · Post by **_gonz_** » Wed Apr 19, 2006 12:19 pm

Sensitivity is one of those specs that really mean nothing.
There is no industry standard manner of testing sensitivity, so... sensitive as compared to what? Theres no even playing field here.

solacedagony · Post by **solacedagony** » Wed Apr 19, 2006 12:23 pm

Sensitivity: A measurement (in dB) of the sound-pressure level over a specified frequency range created by a speaker driven by 1 watt (2.83V at 8 ohms) of power with a microphone placed 1 meter away.

As per http://www.hometheatermag.com/glossary/.
Sensitivity allows you to tell how much output you're getting with the same amount of power.

Robert Wollenberg · Post by **Robert Wollenberg** » Wed Apr 19, 2006 8:57 pm

I should think if you're comparing apples to apples, db at 1 watt at 1 meter type thing, it at least gives you a general idea. And if you have a tweet that's 93 db 1W/1M and a mid that's 86 db 1W/1M, you could probably count on a substancial gap in efficiency there even if the numbers aren't totally correct. If you double the power to the mid you'd gain 3db, but you're still 3db short of equal. But if you were to double up on your midrange drivers or choose a different driver, I would think it would help eliminate some troubles.

solacedagony · Post by **solacedagony** » Wed Apr 19, 2006 9:05 pm

Well, I would imagine almost all tweeters are goign to be more efficient than mids, so that's why I discounted that.
Also, according to http://www.passivecrossovers.com:

"Resistors are components that offering a certain resistance to the current flow attenuate the signal that passes through them but don't modify its response. For this reason, as we'll see later, they are used for aligning transducers with different values of sensitivity — the parameter indicating how much louder a speaker plays than another under the same applied electrical tension."

I'm not saying you ARE wrong, I'm just supporting why I THOUGHT you were wrong. lol I'm still trying to figure all this out.

Robert Wollenberg · Post by **Robert Wollenberg** » Wed Apr 19, 2006 9:22 pm

I can see sensitivities being less important if you're using a bunch of passive crossovers throwing everything out of wack. But I'm using all active crossovers so I don't think I'm affected by all that mess. I don't have any caps or coils in the mix. All digital.

But the question of the thread what how to make sure two speakers are going to work well with each other ... I guess it's safe to say, crossovers aside, their response graphs are probably the key deciding factor?

Robert Wollenberg · Post by **Robert Wollenberg** » Wed Apr 19, 2006 9:41 pm

And to go back on that quote from the website, "using resistors to align transducers with differnt values of sensitivity"

How can that be meaningful at all if "Sensitivity is one of those specs that really mean nothing. There is no industry standard manner of testing sensitivity, so... sensitive as compared to what? Theres no even playing field here."

So does that mean in order to truely know what the "sensitivity" of a driver is, you have to test it yourself? Is that number played with like the power output of an amplifier? I remember speaker companies trying to squeeze in a 90 db 2W/.5M, but at least it seemed they were being honest if you paid attention to the 2watts and half metter issue.

And a final question for solacedagony, if you know all tweeters are going to be more efficient than mids, why discount it rather than take it into considertaion? Does the efficiency of tweets diminish in the car environment?

Since I've decided to get into buying raw drivers and using active crossovers rather than the old fasion component set with passives, I've become increasingly aware of just how little I know about crossovers and their affects. I'm also learning a lot about the drivers themselves.

Jonathan · Post by **Jonathan** » Wed Apr 19, 2006 10:39 pm

Sensitivity is the easiest to be compensated for. Don't worry about that one. Even with active crossovers, you'll be able to control level of all drivers with most processors (or head units with that capability, for that matter).

Choosing based on distortion and energy storage is critical as well. You have to rely on testing for that one. I may do a writeup once I'm wide awake and have some time on my hands.