dave_Edwards

I have challenged this guy with a pretty damn good install----If ya could vote for me and tell me what the vote count is---- http://www.carstereo.com/installs/H2H_profile.cfm?H2HID=6459

Prior to 1970, there were no easy or affordable methods accepted as standard in the industry for obtaining comparative data about loudspeaker performance. Recognized laboratory tests were expensive and unrealistic for the thousands of individuals needing performance information. Standard measurement criteria were required to enable manufacturers to publish consistent data for customers to make comparisons between various loudspeakers. Thiele-Small Parameters In the early seventies, several technical papers were presented to the AES (Audio Engineering Society) that resulted in the development of what we know today as 'Thiele-Small Parameters'. These papers were authored by A.N.Thiele and Richard H. Small. Thiele was the senior engineer of design and development for the Australian Broadcasting Commission and was responsible at the time for the Federal Engineering Laboratory, as well as for analyzing the design of equipment and systems for sound and vision broadcasting. Small was, at the time, a Commonwealth Post-graduate Research Student in the School of Electrical Engineering at the University of Sydney. Thiele and Small devoted considerable effort to show how the following parameters define the relationship between a speaker and a particular enclosure. However, they can be invaluable in making choices because they tell you far more about the transducer's real performance than the basic benchmarks of size, maximum power rating or average sensitivity. Fs------This parameter is the free-air resonant frequency of a speaker. Simply stated, it is the point at which the weight of the moving parts of the speaker becomes balanced with the force of the speaker suspension when in motion. If you've ever seen a piece of string start humming uncontrollably in the wind, you have seen the effect of reaching a resonant frequency. It is important to know this information so that you can prevent your enclosure from 'ringing'. With a loudspeaker, the mass of the moving parts, and the stiffness of the suspension (surround and spider) are the key elements that affect the resonant frequency. As a general rule of thumb, a lower Fs indicates a woofer that would be better for low-frequency reproduction than a woofer with a higher Fs. This is not always the case though, because other parameters affect the ultimate performance as well. Re--------This is the DC resistance of the driver measured with an ohm meter and it is often referred to as the 'DCR'. This measurement will almost always be less than the driver's nominal impedance. Consumers sometimes get concerned the Re is less than the published impedance and fear that amplifiers will be overloaded. Due to the fact that the inductance of a speaker rises with a rise in frequency, it is unlikely that the amplifier will often see the DC resistance as its load. Le--------This is the voice coil inductance measured in millihenries (mH). The industry standard is to measure inductance at 1,000 Hz. As frequencies get higher there will be a rise in impedance above Re. This is because the voice coil is acting as an inductor. Consequently, the impedance of a speaker is not a fixed resistance, but can be represented as a curve that changes as the input frequency changes. Maximum impedance (Zmax) occurs at Fs. Q Parameters---------Qms, Qes, and Qts are measurements related to the control of a transducer's suspension when it reaches the resonant frequency (Fs). The suspension must prevent any lateral motion that might allow the voice coil and pole to touch (this would destroy the loudspeaker). The suspension must also act like a shock absorber. Qms is a measurement of the control coming from the speaker's mechanical suspension system (the surround and spider). View these components like springs. Qes is a measurement of the control coming from the speaker's electrical suspension system (the voice coil and magnet). Opposing forces from the mechanical and electrical suspensions act to absorb shock. Qts is called the 'Total Q' of the driver and is derived from an equation where Qes is multiplied by Qms and the result is divided by the sum of the same. As a general guideline, Qts of 0.4 or below indicates a transducer well suited to a vented enclosure. Qts between 0.4 and 0.7 indicates suitability for a sealed enclosure. Qts of 0.7 or above indicates suitability for free-air or infinite baffle applications. However, there are exceptions! The Eminence Kilomax 18 has a Qts of 0.56. This suggests a sealed enclosure, but in reality it works extremely well in a ported enclosure. Please consider all the parameters when selecting loudspeakers. If you are in any doubt, contact your Eminence representative for technical assistance Vas/Cms--------Vas represents the volume of air that when compressed to one cubic meter exerts the same force as the compliance (Cms) of the suspension in a particular speaker. Vas is one of the trickiest parameters to measure because air pressure changes relative to humidity and temperature

lol nOOb?-----now that my friend is funny!

it isn't running them with less power----it is the morons that try to play them too loud with no real power.

I think Jim enjoyed the "launch action" we did today----and no we can say we "bumped" Dire Straits in downtown B'burg----and like I said----no one cared---hell you could goto class in just your boxers and no one would even notice. PS---Heather loved the french toast plate.

seems you are the only one that thinks so----and you are in Cali---so you don't count.

you can't fit a Brahma 15 in the "side pocket"-----oh---I didn't tell you guys this did I-----This is a leased car----so everything has to be able to be returned to factory----which it can in about----hmmm 2 hours tops.

care to give me some of your ideas---I am always looking for better ways of doing things

That works for both installs. <{POST_SNAPBACK}> what do you mean by that?

3043 watts(RMS) of pure sonic bliss comments?

mine doesn't either----well it can but it won't!

it is a tight race

ok---i will be quick about this---I have a few tracks I wanna burn---I put a blank CD in the CD writer----and I am using Music Match----and it says "put a blank disk in"------I do and it keeps saying that-------it is really annoying.-----------HELP!!! I am using all new disks also. PS----i never said I was the CPU Guru

would I be the oldest----27--------oh wait-----Webster will be there-----lol

well----alot of you know I am a car dealer-----well----we just got done selling the Ford GT we had here @ Shelor's.----happy day for me!!!

I am using the PEQ P9.

the rest was a "house" deal------when you have a collectors car(like the GT) some will pay anything------I know I would NOT buy it-----I am thinking 7 series or maybe a 600 MB.....but that is a few years down the road.

wow----it must be hard----because their sticker is what? $150,000----hell show me an invoice of one less than $100,000. http://www.edmunds.com/new/2005/ford/gt/10...732/prices.html I doubt ANY dealer would lose THAT kind of money

in buisness I do

ok----i need a tally of everyone that is coming so I can let the neighbors know(and Heather---my wife) please pm me if you need directions----Sat. night we are planning on going out to eat somewhere also-----let me know if you need a place to sleep also(we have alot of hotels that are close)

I would talk on how the car audio world has changed even the OEM side of the buisness---and how intergration is now one of the bigger aspects of it-----the Mark Levison system for example----show models of older products and how the engineering has changed the outlook of products---XBL2 for example. just a few thoughts. edit---also on the way the older generation looks at car audio vs. the new----and how not all of us are out to shake everyones windows----it is the journey to find sonic bliss for ALOT of us.

you are more than welcome to use my Magnums pics----if you want

Webster-----wasn't that a 80's child star----or was he a midget? BTW----welcome to the best forum in the known universe!!!

I agree w/ all that thch has stated.

like I was telling Jim last night----this small get together is getting to be huge!-----I love it!