OK, so received mine earlier this week and took a few minutes to drop one in a completed design using the white cone.
Up first is a response overlay between the two woofers in the same design:
The good news - it is a direct drop in replacement with only minor differences here and there that can be attributed to differences in production batches. In other words - if you are happy with an existing crossover using the white cones, but really want a black cone - bombs away.
Here is a distortion plot of said design using the white cone:
...and here is a distortion plot using the black cone:
Ignoring below 500Hz for now, the two drivers are almost identical to each other, indicating very little advantage to the copper cap addition. The break-up induced 3rd harmonic is the same magnitude, but it appears there may be some improvement in higher order distortion.
Verdict: if you are happy with the white cone appearance, I do not think switching to the black cone will yield any audible improvement. If you want the black cone, you are safe using existing designs with the driver. While it is definitely advantageous to have cosmetic choices available to us, especially with an excellent driver at a stupidly low price - I wish I we seeing more improvements in the distortion between 2 and 4K. In reality, though, if crossing lower than the 3+k I did in this design, it is moot and the distortion is very competitive with many drivers at many times the cost. This is still, in my opinion, the best bang for the buck midwoofer on the market.
And for shits and giggles, here is the $50 Eclipse 5-1/4" poly woofer dropped in using same crossover:
The crossover is not remotely optimized for the driver, but it still shows how low the distortion is on that midwoofer. The $20 MCM tweeter is lower still - which speaks volumes to the motor on it. Fix up some of the linear distortion issues on that tweeter (maybe investigate the phase plug?) and it would compete with some seriously heavy hitters out there.
The -2669/-3669 is a very nice driver, and I like the appearance of the black cone.
I have seen your excursion test with the 55-2669 that showed it performing well. Even though the 55-3669 distortion does not measure any lower that the 2669, do you think the motor enhancements will help the 3669 "hold together" better at higher volumes and with more complex musical passages?
I have seen your excursion test with the 55-2669 that showed it performing well. Even though the 55-3669 distortion does not measure any lower that the 2669, do you think the motor enhancements will help the 3669 "hold together" better at higher volumes and with more complex musical passages?
This is where deivers, and analysis thhere of becomes very tough.
With high demand, things like flux modulation, and control of the reverse eddys can mean far more than control of cone breakup. Specially concentric modes which tend to raidiate their power in all directions ultimately being tagged as simply a characteristic of the driver vs. A bad thing.
It seems many manufacturers are adding copper in the motor, despite it not always having a small sign measurable effect, it dramatically helps at high currents to keep the coil free of its own elecrical issues loweing distortiin at volume, maintaining resultion, longer, and preventing back-plate smashing or gap-jumping when its eddys are in phase with an arriving impulse.
Comments
Up first is a response overlay between the two woofers in the same design:
The good news - it is a direct drop in replacement with only minor differences here and there that can be attributed to differences in production batches. In other words - if you are happy with an existing crossover using the white cones, but really want a black cone - bombs away.
Here is a distortion plot of said design using the white cone:
...and here is a distortion plot using the black cone:
Ignoring below 500Hz for now, the two drivers are almost identical to each other, indicating very little advantage to the copper cap addition. The break-up induced 3rd harmonic is the same magnitude, but it appears there may be some improvement in higher order distortion.
Verdict: if you are happy with the white cone appearance, I do not think switching to the black cone will yield any audible improvement. If you want the black cone, you are safe using existing designs with the driver. While it is definitely advantageous to have cosmetic choices available to us, especially with an excellent driver at a stupidly low price - I wish I we seeing more improvements in the distortion between 2 and 4K. In reality, though, if crossing lower than the 3+k I did in this design, it is moot and the distortion is very competitive with many drivers at many times the cost. This is still, in my opinion, the best bang for the buck midwoofer on the market.
The crossover is not remotely optimized for the driver, but it still shows how low the distortion is on that midwoofer. The $20 MCM tweeter is lower still - which speaks volumes to the motor on it. Fix up some of the linear distortion issues on that tweeter (maybe investigate the phase plug?) and it would compete with some seriously heavy hitters out there.
The -2669/-3669 is a very nice driver, and I like the appearance of the black cone.
It is a sexy bitch, though. I converted this design to the black model.
With high demand, things like flux modulation, and control of the reverse eddys can mean far more than control of cone breakup. Specially concentric modes which tend to raidiate their power in all directions ultimately being tagged as simply a characteristic of the driver vs. A bad thing.
It seems many manufacturers are adding copper in the motor, despite it not always having a small sign measurable effect, it dramatically helps at high currents to keep the coil free of its own elecrical issues loweing distortiin at volume, maintaining resultion, longer, and preventing back-plate smashing or gap-jumping when its eddys are in phase with an arriving impulse.