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Discussion Starter #1
I've done a lot of searching here and around most of the other sites. I am in the planning stages of my next build. I currently am running Wayne Parham designed 4 Pi speakers as LCR in my home theater (JBL 2226H woofer, Eminence H290 + B&C DE250 CD). The speakers sound great but I am getting the DIY itch so I am looking to make them full range speakers for two channel music (I have plenty of subs for home theater usage). Hence, the addition of the JBL 2242H (or similar) driver.

I am thinking of building an enclosure around the inverted 4 Pi's (inverted so the waveguide is at the proper height) with a 2242 driver. Trying to get to 8 cu ft with a tuning of 25 Hz, but the enclosure calculator here at HTS is offline with the recent change :help:. Will use DSP to crossover with around 150 Hz.

The 4 Pi's roll off around 90 Hz, they are in a large open basement about 3 ft from the back wall. While I could just build stand alone mid bass modules I prefer the look of a larger tower speaker.

I also have modeled the 2269H driver, and it is pretty beastly! Seem hard to come by, I used the technical manual from a VTX product to get the JBL part number and they "seem" to be available on-line (I am not sure if the store will ask for S/N numbers when time to actually order). The JBL W15GTi is quite a driver and would work well but I am not particularly fond of the aesthetics of the driver. My taste in music, mostly late 60's to early 80's hard and classic rock (with a smidge of classical and jazz) should be fine with a response down to 30 Hz.

Attached are some preliminary drawings of what I am thinking, the 4 Pi is a standard (but sealed) build fully enclosed speaker internal to the larger speaker. Current size: 18.5" W x 60" H x 22.75" D, material will be Baltic Birch (hence the 60" height). I should be able to finalize bracing/vent volume to get right at 8 cu ft [25 Hz tune] which is the same size as the JBL Pro 4645C subwoofer. If I go with the 2269H driver I could make a half-sized 5628 sub. I really like the big JBL subs.:hsd:





I will use the 4 Pi crossover and run the 18" driver only below 150 to 200 Hz depending upon in room response (will measure with REW). Basically the new speaker will be seen by the amp/DSP as a two-way crossed over at 150 to 200 Hz. Thinking of the QSC PLD-series amps, they have plenty of DSP/crossover horsepower for this project. If not, will get an Ashly Protea or DBX processor. Center channel will be a standard 4 Pi (except sealed, blessed by Wayne a couple of years ago and currently in use) driven by a Crown XLS1500 that is currently driving the left and right 4 Pi's.

Comments and suggestions welcomed, this is a very preliminary deign - more of thoughts at this point. Eventually I want to go all JBL, replacing the D250+H290 with a JBL 2452H-SL on the waveguide from the VTX-series. This will remove the ability to use the 4 Pi XO so I have a lot of learning to do.
 

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Discussion Starter #2
I accomplished by end goal in a different way. I was offered a really good deal on two JBL 4645B subwoofers. I simply am using them as my speaker stand with the 4 Pi's inverted on top. Running 4 Pi's as small [80 Hz XO on my Marantz AVP] and the 4645's as sub [sub 1, sub 2 output is used for two DIY Lab12 subs near field (5 ft) behind the listening position].

Vast improvement over my previous setup.
 

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That looks like a nice compromise. How do they sound?
Spent all afternoon listening to jazz and folk music. I absolutely love the addition of the 4645's. I am shooting for accurate sound (in my view reproduction of instruments/vocals that sound like they do in an unamplified environment). So far I really like the sound, the bass is not prominent in this type of music, but I like that I could track the bass lines throughout the entire song, even during sax or guitar solos. :clap:

I need to break out the microphone and run REW. Will get to that one day, for now I am content to just sit and listen to music.
 

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I keep thinking three way monster speaker, had the 4 Pi's for 5 yrs and the itch is getting unbearable.

HF - JBL Pro D2430K compression driver

Waveguide - JBL Pro VTX 90 x 50 (part number 5006815)

MF - JBL Pro 2262 or 2206

LF - JBL Pro 2269

Would go active crossover, leaning towards the dbx Venu360. Starting XO points are 200 Hz and 1000 Hz.

Would go with a big enclosure, old school monitor style (32" W x 44" H x 16" D, internal dimensions). Midrange would be in a sealed enclosure inside the cabinet (.7 cu ft).

Would build two, with a third without the 2269 for center channel (smaller enclosures, tubed to 50 Hz or so....HT processor to set HPF at 80 Hz.
 
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