Another test...
This is interesting and controversial: I simulated the crossover transfer into a active mode, with a tubed crossover, and applied the results in the actual active cross circuit. The results? The frequency response is almost the same, or same, and the tweeter notch is not needed.
But one thing I liked is the "unexplainable" cleaner and "dynamic" (sic) sound via active crossover. Tested also with one 22+22W valve amp with 6CW5 for tweeter, and a 60+60W PL509 tube amp for woofer.
Some friends helped (and one disturbed) the evaluation.
One friend of mine likes active crossover, and said I've had a "obvious" betterment in system. Hmmm... Lets see:
One thing I noted in fullrange systems, apart from eccentric response, is some "directness"/less "fog" in the sound reproduction. Most people say that is due to absence of crossover, but I say: is due to direct connection to amplifier. No coil/cap to rotate de signal current phase, so the amplifier "sees" the driver "naked", ie. without interferences. If one speaker generate some EMF, the coil (for example) will change the phase angle and apparent resistance, and the EMF damping is not the same. Loudspeakers already have a nasty inductance, and one only makes things worse with reactive components addition! Well, I don't bother if this is true or not. The fact is that the active mode resulted in some difference.
This is interesting and controversial: I simulated the crossover transfer into a active mode, with a tubed crossover, and applied the results in the actual active cross circuit. The results? The frequency response is almost the same, or same, and the tweeter notch is not needed.
But one thing I liked is the "unexplainable" cleaner and "dynamic" (sic) sound via active crossover. Tested also with one 22+22W valve amp with 6CW5 for tweeter, and a 60+60W PL509 tube amp for woofer.
Some friends helped (and one disturbed) the evaluation.
One friend of mine likes active crossover, and said I've had a "obvious" betterment in system. Hmmm... Lets see:
One thing I noted in fullrange systems, apart from eccentric response, is some "directness"/less "fog" in the sound reproduction. Most people say that is due to absence of crossover, but I say: is due to direct connection to amplifier. No coil/cap to rotate de signal current phase, so the amplifier "sees" the driver "naked", ie. without interferences. If one speaker generate some EMF, the coil (for example) will change the phase angle and apparent resistance, and the EMF damping is not the same. Loudspeakers already have a nasty inductance, and one only makes things worse with reactive components addition! Well, I don't bother if this is true or not. The fact is that the active mode resulted in some difference.
I've had both. The SEAS really have more controlled and better extreme HF dispersion, making the "image" more convincing, with very wide listening window. More lively sound. And supports more power due to higher mid band efficiency.
Cons are the difficult to hammer into correct response. Not that difficult, but really calls for a proper filter.
Other small comparisions I've listed various posts back in this thread.
Since I don't have any of them, I'm unable to making more tests.
Yes. And one more plus about it:
Most metal dome tweeters uses some sort of diffuser lens directly in front of dome for helping HF dispersion, due to pistonic behavior interacting with wavelenght. People like the late Linkwitz mentions about energy storage in the cavity formed from the diffuser and dome. The DXT instead uses a shaped waveguide for achieving same or better results, so it don't have the energy penalty issue, I suppose.
Most metal dome tweeters uses some sort of diffuser lens directly in front of dome for helping HF dispersion, due to pistonic behavior interacting with wavelenght. People like the late Linkwitz mentions about energy storage in the cavity formed from the diffuser and dome. The DXT instead uses a shaped waveguide for achieving same or better results, so it don't have the energy penalty issue, I suppose.
SB Acoustics SB17NAC35-4 measurements! - diyAudio
In fact, the poly version is not better than the metal version...for some, is worse
system7, I considered using another crossover order, and cut the tweeter lower, but the temptation to get the LR2 was big (and to experiment with stepped baffle). Personally I'm about to give up the decision, because the response does not behave well at vertical, although the end user of this box (which is a friend of mine) is already amazed with the current results. For him I already declare terminated the project. He is used to listen mini-systems and micro-systems, and this is already a revelation for him. And for serious listening, the window is comfortable large (far larger than full ranges, for example).
By the way, at this time will be difficult to change the box front, so I'm stuck with stepped baffle...
Follow the resulting crossover, for now. The component quantity is based on Troels project. The tweeter notch is made oversized, to cut down the response at tweeter resonance (is awful sounding) and to match the 100µF elcap.
By the way, even the Troels solution has some response anomaly near cross point.
I don't used speaker crossover simulator to obtain the values. I played with component values, starting from some other LR2 projects, and arrived here.
A remark about vertical response: It gets worse as it rises above the tweeter level, and not much worse towards the speaker down. My preferred solution? Use the box upside down!Or use a stand to match the woofer a little higher than ear level.
Friend, I would very much like to build this crossover, but I have no competence to do it through this diagram. I would need to know the wire gauge, inner diameter "core", how many wires per layer. Please, I would be grateful.
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