what exactly is Q?

I've heard a lot about building a system to the Q of .7 or 1.1 or whatever, but what exactly is that.  Is that the enclosure design or the all around system design.  When I had heard about it, it was someone design an enclosure for SQ and they said they were building their box to the Q of .7. Can someone expalin this to me.what!?!?! you want some??

Generally speaking, the lower the Q a system has, the thinner the bass will sound. A Q of .5 will sound very thin for most people, but it will offer the lowest overall cutoff frequency. It will have a higher F3, but due to the VERY shallow slope of the rolloff, the driver will go deeper in it's overall frequency response. It will have lower power handling, but you will have the absolute smoothest response with a minimum of resonant peaks, both output and impedance. A Q of .707 is what most people call "max-flat". It will offer good power handling with reasonable rolloff and extension. It will do this also with a decent trade off in resonant peaks. It will usually sound pretty good. A Q of 1.1 is a maximum power handling enclosure, and will sound like CRAP. Their response is VERY boomy, with many high level peaks in output AND impedance. They will not go very deep at all. It usually happens when an enclosure is too small for the driver. This is what my enclosure is right now (or close to it) but I have equalized many of the peaks and dips out and I am brute forcing it into its desired output curve. This can be (really, it is, there is no "can be" about it) very hard on a driver, as it requires MUCH more power be available (and used) but I have enough to do this. The Eclipe Titanium 12 is an excellent woofer for this approach, but as I said, it DEAMANDS MUCH POWER be available... (and with my DA7232, I think I can say I have the power necessary) I do not usually recommend doing this, but I really did it first as an experiment in my house, and was quite pleased with the results. If you want to try this, I will not be responsible for you popping your Sony Xplod 10 inch "sub" and hooking it to a HiFonics Brutus... Get it? This method requires a VERY high power handling woofer...It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Great explanation of how to use it in speaker designing!  The simple definition of the term is:  "Q" is a measure of the relative damping factor in a loudspeaker system.  Higher Q factor = more speaker dampening.  Speaker dampening = resistance to cone movement.Support the12volt.com

Steven Kephart wrote: I always thought speaker damping was the light application of moisture to the cone.

Or when I cry over my spelling errors!  :)

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From www.dictionary.com:

"damp·ing    ( P )   Pronunciation Key  (dmpng)

n.

The capacity built into a mechanical or electrical device to prevent excessive correction and the resulting instability or oscillatory conditions."

"dampening

2. To depress; to check; to make dull; to lessen."

Hmmm.  I suppose Damping would be the most correct word to use.  But I still think dampening is just fine as well, so you are ok.  That is unless you were talking about something else. 

Steven Kephart

Adire Audio

 Damping it is and should have been!  And please, feel free to both make jokes, and to make fun of my copious spelling errors.  I'm the first to admit I wish there was a spell checker on this forum....Support the12volt.com

if your serious about spelling errors. i run Opera as my main browser, and if im ever concerned about spelling errors (which i rarely am, i just dunn care), i hit preview post, and i am able to copy a word to dictionary.com or encyclopedia.com, both are very handy sites, and i would recommend the browser to anyone, solid piece of software :-). btw - there is also a plugin for opera which allows you to install a built in spellchecker but my last attempts to get it working failed.

ok, so how do you design a system to the Q of .707, is it mainly the enclosure design? basically all you did was give me a definition, i wanted to know how to design it.what!?!?! you want some??