The tweeter is capable of max power of 40 watts which translates to 113 dB/M. There should not be any problems with the crossover at 4k or higher, 4th other or higher.
To answer the question about where I am headed. I am continuing to refine my dipole speaker designs by achieving better control of directivity and also trying to make the speaker as economical as possible for the DIY community. Music and Design is a for the love of it venture.
To answer the question about where I am headed. I am continuing to refine my dipole speaker designs by achieving better control of directivity and also trying to make the speaker as economical as possible for the DIY community. Music and Design is a for the love of it venture.
I don't understand compensating for the Fletcher–Munson curve when eq'ing loudspeakers, we can't tailor sounds in real life to compensate for the curve.
Sound pressure should be the same for all frequencies in loudspeakers to mirror real life? No?
Let's assume for a moment that the recording engineer mixes the recording using flat monitors. Then why would there be any need to correct for HRTFs or anything else for that matter. It should be "build in" to the recording. Cutting, boosting or any deviation from the response of the monitor is simply saying 1) the recording engineer got it wrong, 2) the speakers being used for play back are significantly different from those used for monitoring, 3) the listening environment is significantly different that that used for monitoring, 4) personal preferences are different.
This is why I design for flat response. I don't claim it to be correct for everyone's room, recording, or preferences, but it provides a standard reference from which the listener can make his own adjustments using the controls I build into the speaker/crossover. And with this new Note using a dsp crossover the listener has great freedom to tune the system to his environment and taste.
I also feel that when I design a speaker I need a fixed reference. For example, how would I be able to evaluate the difference between the Note and the NaO II which could be attributed to polar response if the two system had different axial response?
And as I said when this was discussed before, if there is a need to correct for HRTFs then it should be done in the recording, not the speakers. And if not the recording, perhaps somewhere else in the play back chain; the CD player, a change in the RIAA phono curve, the preamp, the power amp... It just doesn't make sense that every recording engineer got it wrong on every recording.
This is why I design for flat response. I don't claim it to be correct for everyone's room, recording, or preferences, but it provides a standard reference from which the listener can make his own adjustments using the controls I build into the speaker/crossover. And with this new Note using a dsp crossover the listener has great freedom to tune the system to his environment and taste.
I also feel that when I design a speaker I need a fixed reference. For example, how would I be able to evaluate the difference between the Note and the NaO II which could be attributed to polar response if the two system had different axial response?
And as I said when this was discussed before, if there is a need to correct for HRTFs then it should be done in the recording, not the speakers. And if not the recording, perhaps somewhere else in the play back chain; the CD player, a change in the RIAA phono curve, the preamp, the power amp... It just doesn't make sense that every recording engineer got it wrong on every recording.
That is true, which is why I provide the ability to make such adjustments. But I would again emphasis that shelving down the top end reduces both the power radiated into the room and the level of the direct sound. I still think that is the problem. That is, it is not the level of the direct sound the needs to be reduced, it is that there is too much power radiates into the reverberant field at high frequency.
After reading SL's LX521 page which is now up, he states that he is still shelving down the tweeter. He also states that the side walls should not be too damped because it absorbs high frequency energy. In that context I can understand why he pads down the top end. But that is also where I disagree. It seems he is attempting to maintain the ratio of direct to reflected sound as the frequency rises. My gut and my listening experience tells me that the ratio of direct to reflected sound should increase somewhat as the frequency rises. All this is highly dependent on the room acoustics, the speaker radiation pattern vs frequency, and the listening distance.
These are the main factors and 3) is even more important because speakers and the listening room create a new system with new characteristics even if the room is heavily damped or the speakers are very directional or both.
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Guess that's the multi-million dollar question, "What is the optimal direct and power response?". Or maybe it's more complicated and we need to look at the specific reflection pattern within a room?
Well there has been a long running thread here, I think entitled Speakers and Room as a System. When you look at the variables; speaker axial response, polar response, room characteristics (not just RT60 but what walls are damped how much), speaker position, listener position.....
Just noticed that the cost of the LX521 is listed as about $2460 for parts; driver, crossover active crossover parts and plans; less amps, passive crossover, wire and wood. I estimate equivalent cost of parts/plans/active crossover for the Note II Rs at about $1840; drivers, miniDSP 2x8, and plans. Additionally, the miniDSP is an investment that can be used with other systems.
Yes and no. The issue is when somebody listens to the sound at a different SPL than the recording engineer intended. When that happens, the relative loudness of the treble and bass are not the same as what the engineer hears, so volume control in itself throws off reproduction accuracy. Plus, when going from record to record, or even song to song, there is a different SPL requirement...
I agree with that, and see it as an advantage for dual tweeters (as opposed to dipole tweeters). The high frequency rolloff can easily be applied to the rear tweeter only. One has to be careful with phase in the filters (if there is to be any dipole cancellation at the tweeter's low end), and as always the front wall should be as diffusive (not absorptive) as possible (regardless whether the rest of the room is "live" or "dead"). "Tuning" the reverberant rolloff is, of course, room dependent as well, but like you I don't believe that rolling off the direct sound is the best way to deal with that.
One of the things that SL has managed to do with the LX521 is cure the "bloom" that ORION suffers . . . standing in the null (at BurningAmp) there was none of it . . . the null is a null from the bass all the way up. The result, of course, is that on axis one hears the speaker and in the null one hears the room. In this regard at least the LX521 is a significant improvement over ORION, at least in a room with "live" side walls (but not enough, I think, to induce me to build a pair).
The LX521 has the expected problems with vertical polar (SL suggested that I should listen to them sitting down, rather than standing up and walking around as I am wont to do) . . . I know that you are familiar with this issue
. There are still "issues" to be resolved, but this speaker is another step closer to defining and addressing them . . . it's the best I've heard. It's got me seriously thinking about "revisiting" the ORION tweeters (I see no reason to change the woofers or the W22) . . .
Sure, absolutely.
I wasn't speaking in terms of compensating for the recording, but rather for individual tastes.
I design speakers to be flat and to hell with the recording engineer.
I can't play a guessing game. Engineers should expect that speakers are designed to be flat, that's their job.
What happens if I start tailoring the FR to compensate? Say I put a dip at around 7kHz to tame sibilance for pop recordings.....
What happens when I play jazz? It will sound muffled and flat.
That's just one example.
It's a "lower part" thing. Like all domes the Millennium begins beaming as frequency rises. In its lower range it's a point source, and the radiation pattern is determined by the baffle. It would take more than some wool to control it, but perhaps a ring of ""703" type rigid fiberglass could help.
It's perhaps instructive to review how pattern control works in ORION, especially in light of the addition of a rear tweeter. ORION is dipole (or dipole like) through the bass and most of the midrange (W22). The upper part of the W22's range is "dipole like" as the driver begins to beam (which, of course, reduces and eventually eliminates "dipole cancellation"). The crossover point is about where the "beaming" pattern matches a dipole pattern. In the original ORION (single tweeter) the pattern then transitions to roughly hemispherical. In a uniformly reflective room the power response stays relatively flat . . . the rear lobe of the W22 being replaced by the side radiation of the tweeter. Power response then begins to fall as the tweeter beams (assuming flat on-axis tuning). This worked fine for frequency response, but not so fine for "soundstage" and "imaging", which led to the introduction of the rear tweeter.
But with the rear tweeter came the "bloom" problem . . . transitioning from dipole to what was essentially omni (in power response) led to a hump in power response in the lower tweeter range. Correcting that with equalization led to a dip on-axis. It's a classic problem, rather like baffle step except higher in frequency . . . you can get one right, or the other, but not both at once. It led SL to do a lot of never-completely-satisfactory fiddling with the ASP (crossover/equalizer), and made overall response dependent on sidewall reflection in the room. The LX521 resolves that by being true dipole through the mids, and by the time it is crossing to the tweeters (at 7kHz) they are already beaming, so there is no side radiation to speak of. The vertical polar is still, as it always is with multiple drivers in a line, a bit of a mess . . .
If one felt a need to "improve" ORION (without going to an altogether new set of drivers) it might be easier to just replace the pair of Millennium with the upper-mid and tweeters from the LX521 (or something similar). If you're doing that on a new design, however, there's little reason to keep the (relatively expensive) W22, so you get something more like what SL has done with his new speaker.