TS Parameters are simply measurements of a driver that tell us everything we need to know about the specific driver and how it will behave in certain enclosures and it allows us to maximize the drivers performance by designing an enclosure that is optimized for a specific driver. This is why pre-fab boxes are less than optimal for a given driver. You can get away with this for a sealed enclosure but never use a pre-fab ported or bandpass enclosure if you want to get the most out of your subwoofer.
All manufactures of speakers provide all the necessary TS parameters to allow you to custom build your own optimized enclosure. I have attached an example from JL Audio website showing these measurements. In the program I have attached you can just plug in these values and then key in the desired size enclosure and the program will tell you exactly how the subwoofer will perform granted you understand the values. I will be very basic but I will tell you what they mean.
F3 = the lowest frequency the driver can play in the enclosure before it begains to attenuate. (The lower, the better!)
FRMAX = this is the frequency where the woofer plays the highest output in the given enclosure (Again, the lower, the better for a subwoofer)
Q = how tight or accurate the subwoofer will play in a given enclosure. (Anything >1 will be a bit on the boomy - Looser side and anything = or <.6 will be very tight and accurate at the expense of a bit of efficiency.
I tend to prefer a Q of .7 to 1 but anything above 1 is too loose for my taste. Less than .7 is a bit to dry.
BTW I am not sure a pair of 8"s will fit where you want them in a down firing config. I would recommend using (3) 6-1/2 " subs if you are dead set on that location. The JL 6"ers are damn impressive for thier size. Parts Express also has some Tang Band 6" ultra long throw subs that are very good as well and much cheaper than the JLs.
Downfiring boundry loads the drivers and your bass output will be awesome! You will really feel them kick too!
I would port them in order to get lower bass response. These subs would also play some sick midbass duty as well. 200 to 300 watts would the max I would use for them as small sub drivers just wont take a lot of power and they really dont need a lot to do the job.
Don't be intimidated, I have already done all the math equations for you with my software program.
__________________
To the optimist, the glass is half full. To the pessimist, the glass is half empty. To the engineer, the glass is twice as big as it needs to be.
|