No need to be sorry It's perfectly normal, I will edit and work on a summary, the original idea I had have changed a lot since the beginning.
As a beginner in this I was not really able to make informed decisions in that matter, at first I thought just simulating a crossover in VituixCAD with the specs from the manufacturer was sufficient, but ScottG & Kimmosto where nice enough to help me (try to) understand that it's not a good workflow to succeed, and now I am following ScottG advices on his proposed design as he know a lot more than I do.
Hopefully in the process with the help I have (from anyone) I'll be able to be more in control for my future projects, but at this state I will make work with what I can.
From what I think I understand
The AXP-08 have a high sensitivity but in the range I will use them and the baffle-step it should be able to link with the FF85WK that seem to be close to 90db at the crossover frequency
Anyway what should I do when I encounter contradictory information's and I am unsure of which is valid?
I understand I think, so basically it's like a horn-loaded at the back, but this one one is a long squared tube with no taper, and the angle of reflection is narrow, by shortening that tube and/or tapering I would increase the angle of reflection.
ScottG advised to make the tunnel narrower by covering the tunnel sides top & bottom with lossy padding, so I guess he have some result in mind for that setup.
Ho so in that case an upward reflector at the exit of the tunnel to direct the reflection to the ceiling.
Floyd Toole? Was it a recording from a presentation ?
I thought that an IEC baffle was useful in designing speakers by measuring the frequency response without including the diffraction's from the shape of the speaker to perturbate the measurements on and off-axis, and by so allowing to simulate the diffraction and experiment with front faces using VituixCaD, how can I make a decision about the general size and driver placement without having to redo multiple time that box ?
Please let me know If that workflow logic fail?
PS: I'm afraid I am dispersing information's for my project on two threads, would you mind responding in the other thread and consider this one out, as the repair of the LS plan not possible ?
That would work if you'd tune them deep and cross them over very low, like a subwoofer at ~120, max ~150 Hz. That would use none of its advantages (wide frequency range usable, high spl, low cone weight) and instead make all drawbacks of the driver really 'shine' (very expensive crossover parts at that xo point, low excursion, medium-low power capabilities) and on top of that increase the distortion of the FF85WK by a lot because then it has to make a lot more excursion.
I'm sorry but that pairing does not make any sense. Don't forget: The Fostex will lose 1-2dB because of the crossover and you got no reserves for any correction whatsoever. None. You cannot increase the spl passively! Go active (dsp) or use a different FR or different woofer.
- Try to get other information sources.
- Try to learn the basics. There are courses, books, videos, guides and examples out there. You don't have to make every mistake by yourself.
- Try to follow arguments logically, try to find the weak points or ask yourself or others for disadvantages of a solution. I initially doubted the 93dB of the Gradient and suspected they would reach the 93dB only at the upper mids and/or because of a very low impedance but then I found measurements opposing that and showed the combination will not work.
- Apply the basic rules and mechanics. The mid and high drivers have to be louder or at least of the same spl as/than the bass to pair up. If it sounds too good to be true, it probably is.
- Try to understand the concept of the offered alternatives and that you'll likely have to change what you've been working on so far.
- Ask yourself if someone actually wants to help or wants to fanatically just propagate his own 'perfect' standards (ofc that's exaggerated). If all you've got is a hammer, everything looks like a nail. Check, if he himself got a flexible, adaptive point of view and can work with something else too (and not just his one idea).
- For some problems or certain situations are several solutions possible. For some, there is only one (unless you change more of the situation). There are combinations which will not work.
- Ask for the advantages of an offered option. Ask for the disadvantages of it, too. Or, if not already explained, how something works or why/how it applies to your problem.
- Verify the informations you've got with your own simulation. (Any simulation will show the pairing of the FR and the midwoofer will not result in a well designed passive speaker)
- Don't try to fight physics or get things 'working' with force. You can't cheat physics.
- An enclosed volume with a smaller opening/tube/channel attached will work as a resonator.
- A resonator will resonate at some frequency or multiple ones (TML).
- If the resonances are wanted (BR, TML), it's okay but check if they actually wanted.
- If the resonances are not wanted, check if they are outside the frequency range you want to use. If they are, np.
- Such a construction would pose as a bandpass, at least for the back energy. Do you want that? For a dipole with a fullrange, very likely not. Usually the same response from the back as from the front is what's desired, otherwise it would only work as a dipole in a certain range.
- Such a construction would restrict the backwards radiated sound in pattern very much. Do you want that? If yes, would it probably better if there wasn't any back sound comming back?
Well, I disagree. I don't know what goal he wants to achieve by that but that doesn't fit the concept of a dipole. Maybe it would be more clear if he described exactly what target points he's persuing with that. And maybe it would help if you could describe what you actually want to achieve and it would help a lot more to check if that goal is reachable or not.
No capes! Erm, no tunnel. Tunnel and reflector doesn't work in combination, it contradicts each other.
Floyd Toole? Was it a recording from a presentation ?
Yes, Floyd Toole. Note he didn't go into dipoles, non-parallel positioning (i.e. diagonally used rectangle or square room), headphones or omnidirectional speakers.
Usually you've got restrictions on how big the speaker may get, upper and lower limit because of the space and positioning available but also on what enclosure volume the bass driver needs to work properly. You've also got the height of the tweeter set, which is the same as the ears (usually the listening position, sitting, ~1m). That often leaves just a small certain range for the rest of the parameters. To make such measurements is beneficial if you want to build more speakers with the same drivers.
On your project and situation, it does not provide an actual advantage. It got three disadvantages though: You don't have to juggle with more/too much variables in the simulation. The simulation can't work with the backwards radiated sound and the room reflections so you can only rely on the simulation in a limited way anyway. The simulation has to be verified by measurement anyway (at non-dipoles too), so you can drop the effort (and probably added error margins) without any drawback.
Aside from that, you'd need an (actually very big) enclosure to make standard measurements of the woofer. And you have to build a system to swap the baffle (or a part of it) because of the different cutouts of the drivers. That takes up much more space most ppl are willing.
I will if you write a summary, details of your goals and a complete description of the signal chain and if active/dsp is an option, a list of requirements (max spl, how deep in the bass etc), of your preferences (music, important characteristics of your listening preferences). And ofcourse, your budget.
You have no idea what you're talking about. We are talking about PASSIVE speakers. If the FR is not loud enough, you cannot increase it to the same spl as the woofer passive.
I'm simply fed up you bring up the same, completely wrong crap over and over again at any random thread where it doesn't even remotely contribute to the topic, situation or understanding, let alone helping in any way.
Yes, because you are too ignorant to learn and to use, and that applies to both.
It can, if..
..you are willing to take the highly increased Q and overswing
..you are willing to take the vastly worse decay
..you are willing to take the phase changes
..you are willing to take the immensely higher group delay
..you are willing to take the worse impulse answer
..you are willing to limit the bandwidth
..you are willing to take the low impedance (guess where the energy for that comes from?)
..you are willing to take the immense hit on the SQ
..you are willing to accept the influence on the crossover (if it can be done at all because the filters interact)
..you are willing to pay for the parts (usually more expensive than the driver)
..1-2 dB increase are enough, because you'll have to get the bump on top flat again
Which means, it's never even an option. Please, show me an example in a simulation.
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Again, total BS!
That graph does not have anything to do with a speaker. Take a simulation of a 2 or 3 way speaker, no matter if it's Boxsim, Virtuix or whatever but use it with a speaker and show the impedance and how it works with the crossover.
Funny you're using coils with 1,1mH with just 10 mOhm (milliOhm).
And just a little hint: A delay of just 1ms equals a distance offset of 34,3 cm!
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