I've posted about this design before, but am looking for help as I continue to refine the sound and design a crossover topology that best takes advantage of the components in the system that I've built.
Design goals:
- Build a speaker that sounds great with these great components that I can have for years without the urge to upgrade.
- Build a sensitive speaker that can be powered, in part, to adequate volumes with my 300b amps and sound good in my small listening room.
- Build a speaker that takes advantage of the MiniDSP for cross-over/EQ duties.
Background:
- I had the opportunity to purchase a number of excellent JBL parts for a very reasonable price. These include 2 x 2226J 16 ohm woofers, 2 x 2445J 2" Compression Drivers, 2 x 2405 super tweeters and 2 x 250 Hz tractrix waveguides.
- I also picked up a miniDSP 4x10 HD for my desire to not spend a fortune on crossover components while I tweak the crossover.
- Amplifiers include a pair of 300B monoblocks, which power the 2445s, and 2x Crown D45 amps, which power the 2226s and 2405s.
- I've been living with 2226s built in what I would call "draft" enclosures: ~ 4 cu ft. vented MDF enclosures tuned to 45 Hz with the horns/waveguides and super tweeters mounted on the top on the enclosures. I lift the bass with DSP.
- They sound pretty good as-is and give me the sense that these components could sound exceptional with the right crossover configuration.
So that is what the thread is about -- the next steps in putting together this system.
The drivers:
- The JBL 2445J is a 2" compression driver with a titanium diaphragm. Part of this build will be to replace the stock diaphragms with the Truextent Beryllium replacement diaphragms. I have these coupled to 250 Hz tractrix waveguides, and mounted on aluminum stands.
- For woofers, I have the JBL 2226J 15" 16 Ohm drivers. I am pretty happy with their performance in the 4 cu. ft. enclosures, but they could be better -- I think giving them a bigger enclosure, and tuning them deeper could improve their performance. I also have the MiniDSP available to me for tweaking.
- The super tweeters are 2405s. They are crossed over at 8 kHz and I find them kind of harsh. They may stay in the system or may not depending on the performance of the 2445Js with new diaphragms.
I am looking for help on how best to measure this system and design the crossover using the MiniDSP.
Right now I have my crossover is configured as follows.
Woofers:
20 Hz LR4
500 Hz LR4
35 Hz +8 dB Q 0.8
Midrange:
500 Hz LR4
8000 Hz LR4
1000 Hz -3 dB Q 1
400 Hz -4 dB Q 2
.3 ms delay
Tweeters:
8000 Hz LR 4
1.05 ms delay
I also have a protection cap network for the MF and HF drivers.
So anyways -- looking for some inspiration, ideas, and feedback. If you are interested on where I am taking this, please feel free to follow along. Hopefully I can turn this system into something special.