JP2 Project Suggestions?

[DIY_newbie]

I've been reading this board for quite some time trying to get an idea of what kind of speaker I wanted to build. I've always liked the sounds of pure ribbon tweeters and on an impulse I bought a pair of the Fountek JP2s on closeout. Unfortunatly I have no idea of what sort of speaker to build.

Please keep in mind that this will be my first speaker project. That being said, I've been reading alot about the PHL midranges and think I might want to do an MTM or 2-way setup with the PHL 1660s although I've also seen alot of people post about the 1120/1220s ??? Since I'm new to speaker building I thought making an open baffel construction might be easier, but from what I can gather the XO and tuning is an artform?

Any comments, suggestions would be greatly apreciated.

--Chris

[Snickers-is]

Buy 8 good bass/mids and make a 2,5-way MTM.

[thylantyr]

If you want a MTM using PHL, try the PHL 1240 (or 1340);
http://www.e-speakers.com/products/woofers.html

Then mate to a subwoofer.

If you want more muscle skip the simpler design and 'Go Big'
and build a 3 way with option to add a monster subwoofer later
in it's own seperate box.

Something like this.
Finally, my new LAMBDA-PHL-Esg3 speakers are done. Check them out.

You don't have to use those exact drivers. Use the 6.5" PHL,
1120 or 1660 'pure midranges' and see if John can build you
a Lambda TD series woofer with faraday motor
John --> support@aespeakers.com

I prefer the 15" but 12" would be fine too. Port the woofer or
run it sealed, works both ways well. I prefer ported.
Do whatever you want with the midrange, sealed or open baffle.

Make a one channel test box first regardless of what you decide upon.

[DIY_newbie]

Thanks for the suggestions thrown out so far. Since this is my first attempt at speaker building I had a couple of fundamental questions.

Looking at the SPL/Freq chart for the JP2s it looks like they will do a pretty good job down to around 2Khz. Does it make sense to use a midrange driver with a tweeter that can produce down to 2Khz?

SPL/F graph : http://www.fountek.net/JP2techgrah.htm

Since human voice is roughly in the 85hz to 1250Hz range would it make sense to pick a single "midbass" driver that will be able to reproduce the entire range of human voices instead of spreading it over a true midrange and bass driver? The PHL 1220/1230 look promising from the data sheet :

"careful design using A/B listening tests to select technological solutions, which authorizes their use up to 2.5kHz without any
compromise, and up to 4.0kHz with full preservation of dynamic
behavior (Compromise is on directivity pattern only)."

PDF DataSheet : http://www.phlaudio.com/datasheets/17_pdf/1220_1230.pdf

Thanks in advance for the help guys!!!

--Chris

[thylantyr]

When it comes to DIY audio you can choose to take any approach
you want

Many people like a normal system using a tweeter and midwoofer
(combination woofer + midrange) in sizes typically 6" - 8" then
mating this with a subwoofer. /simple

Other people may want more horsepower in their sound system
where they like high quality sound with higher sound pressure.
They find the smaller 6" - 8" midwoofers lacking the strong
bass/midbass they seek because the driver is too small (unless you
array them ). If you drive the midwoofer hard enough into high
excursion you may also introduce midrange modulation that may be
audible (vocals warbling, ie, talk near a spinning fan blade to
mimmick this sound).

They seperate the job of midbass by using a dedicated good sounding woofer capable of being crossed over higher without
losing sound quality - (not woofers used for subwoofer duty, instead
a wider band woofer). Some of these specialty woofer may lack in
subwoofer duty because they are not high excursion monsters
therefore you still may desire a dedicated subwoofer.

By using a larger woofer like 12" or 15" you get clean bass/midbass without over driving the woofer. The midrange is happy because it's
a dedicated midrange, not combination driver like a midwoofer
and it's not driven into high excursion and it may offer cleaner sound
overall when you crank the tunes.

A typical crossover frequency for this may be around 200hz - 400hz
the midrange and woofer. The 3 way design will cost more because
you need to find the special 'good sounding' large woofer, not cheap. ie, High end Focal, TAD, JBL, PHL or that Lambda TD w/faraday motor come to mind for this application. You can probably use other woofers if they meet spec for this job.

Because I like higher spl with high sound quality the 3 way design
is the lesser of the two evils. I wouldn't worry about seperating the
lower midrange sound between two drivers because my ear is
more sensitive to the upper midrange sounds.