It looks a bit bumpy, but this isn't actually too bad. It's a result of speaker and room.
The Eminence bass level is higher than the Supravox , but I've deliberately set it like this .
I also tried moving the bass crossover frequency up higher, but sonically it sounds best like this.
You can see the 215 rolls off from about 5Khz, it doesn't sound as bad as it looks, indeed I didn't think it needed a tweeter, till I heard one in place.
The orange line is the target for correction , and Dirac does a pretty good job of getting very close to the target. It cant compensate for the roll-off above 5Khz , but it follows the target to there.
But it does show that for true full range a tweeter is needed. The problem is finding a high efficiency tweeter to match the Supravox.
I've used ribbon tweeters before, with limited success, they can be thin and metallic sounding , however I've heard very good things about the RAAL ribbon tweeters, some claiming they sound unlike any other ribbon.
I ordered a pair of the 70-20XR from Russel Story at Stones Sound Studio and installed them alongside the Supravox.
Well, the claims were valid, these are the best sounding ribbons I've heard and match the 215's wonderfully well. They have quite amazing dynamics , seem completely unhindered and play as though they have much higher efficiency then their 92dB.
Detail is all there, but not in a metallic or tizzy way, its just open and realistic.
They don't sound as though a tweeter has been added, they combine effortlessly with the 215 to give a truly full range , organic and exciting sound.
I simply used a 3.6uF capacitor as passive crossover for the ribbon, and will experiment further with different values and adding an inductor.
Here is measurement of the complete 3 way of Eminence, Supravox and RAAL. Dont forget, this is speaker and room. A bit of juggling of levels and and the bass's DEQX EQ would get this even better, but I'm going to rely on Dirac to sort it out at this stage.
And here is the corrected response.
And here is the impulse- impressive!
I've had mixed results with Dirac, it doesn't always suit all types of speaker/room correction, sometimes the correction is worse than the problem, but here it has done a superb job with the Eminence/Supravox/RAAL combination.
Building this system is not in-expensive, but frankly I doubt you could get the same exciting , realistic and satisfying sound for many multiples of the cost.
I've heard very expensive (>$20K)box speakers that cant do what this combination does.
Defined, tonally correct bass, the dynamic vividity of high efficiency near full range field coil , and the ribbon tweeter that sounds like it's not there, yet everything is so correct and beautiful.
And that is the perception of live , real music.
Next is to do a bit of fine tuning and put the drivers onto a nice furniture grade baffle.
