Hi folks!
Thanks for all the kind comments on this key milestone for the Directiva r1 speaker!
Before I add some of my own comments about this particular review,
I would like to thank @amirm for his support and @ctrl for his outstanding contributions (and perseverance). I will get around to responding to all of the directed questions/comments in later posts, but also want to acknowledge 2 other early design consultants. One being Rick Craig who collaborated on the passive radiator and tweeter selection. Another was
@DDF who helped with the tweeter selection and evaluating box alignments.
So as Amir indicated, Directiva started as his idea and really had only a few requirements:
1. The speaker should be an active design
2. The speaker should attain a high Olive score (a lot more goals buried in here ofc)
3. The speaker should (preferably) use the Purifi 6.5 woofer
At a high level, I added a couple more goals. Make it easy to build/attain and a target price around $1000. Pleased to say, most of these goals were accomplished with the exception being the cost is a bit higher. As mentioned, the woofer is a bit pricey, so allowed that constraint to flex a bit. More details are in the
Directiva thread, so for the sake of brevity, will not repeat here.
Amir asked that I comment on the tweeter. As the main Directiva thread details the alternatives, the short answer is that the Seas DXT tweeter offered the best performance/performance within the overall budget constraints. It is also a proven performer that the
@ctrl and other experienced designers approved.
A quick note on a key implied requirement (of my own). The speaker would be targeted to be able to be used for music listening at 3-4 meters in a medium size room (~50 cubic meters) and produce solid bass down to 40 Hz (even away from walls). So, this speaker is designed to be used a far-field monitor. This pushes the Purifi woofer a bit, but one is up to the task and two should be quite satisfying (without a subwoofer). This was my main contribution to the design, most of the rest is
@ctrl's fine work.
Since most of the review speaks for itself, I have only 2 notes beyond what
@ctrl has already posted. While I have improved my speaker measurement rig considerably, it is not a Klippel and am limited to how low I can reasonably measure. However, am confident that the major resonances in Amir's distortion (and likely CSD) plots are not due to the speaker, but due to the amp/mindisp resting on top of the speaker. The only major distortion I encounter is around 400-500 Hz and it is primarily even order.
Second, I am not very tolerant of hiss from my equipment. I am using a Hypex MC252MP amp in my test setup and so perhaps is quieter than the SMSL amp that Amir used. To further reduce hiss in the future (and better protect the tweeter), I plan to use a hybrid active/passive crossover for the upper frequencies.
Finally, would like to again express my gratitude to
@ctrl for his collaboration on this project. He deserves the credit for all that was done well in Directiva and any shortcomings are (likely) my fault!
Cheers,
Rick