What is this?
BL^2/Re value of the 18XL1600 is 132 (0,55 considering Mms). Did you meant the 5FE120 from Faital?
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Then it will sound pretty much the same.
Again, Fourier to the rescue - the rate of transient attack is determined by the high frequency response.
A sub will have a low pass filter which removes any extreme transient content anyway!
This is what your LP filter does to a square wave - there is no rapid transient attack in the signal fed to the sub. The leading edge of the square wave is made up of ever-increasing harmonics, so if you need good transient attack, you need good tweeters!
(Plus, you have yet to define 'kick'!).
I fixed the name... sorry... Its a chart... motor strength (BL^2/Re) and motor strength per gram (MMS). If I were to say these specs are accurate, it looks like the FaitalPRO has much more motor per MMS, double what scan speak is showing... it would be easy to point the finger at this aspect as the reason why bass was less impactful on the scanspeak.... I am still pretty sure that the effect of this on the signal will be seen in Group Delay/Time to peak SPL.
Speaking of Q.... the Scan speak Qes says 0.3, the FaitalPro Qes is 0.5.... based on that, I would not of predicted this outcome but I will keep this in mind in the future.
These are the drivers I am designing with
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But they sounds different in a way I described.
I don't care what Fourier did or said, the mentioned drivers still sounds different in a way that I described.
I defined it, that sharp kick feel in your chest created by the soundwave(s). I don't care if there is no mathematical formula for more scientific defining what bass kick in the chest is. I mean that kick I am (and others) talking about.
I also think the kick sound is a combo of low ad high frequencies, where the highs are the transients and overtones of the low. So you would need a good frequency response over a wide range that is in phase, low distortion, well damped (but not overdamped) and low group delay. I'm relative sure that there are many ways to get there. A good driver is a start, but only the start. The total speaker, and especially the crossover need to be right to have that and you need enough undistorted volume to really feel the kick.
The best kick sound i heared is with a (custom) sealed box with a woofer that goes low but goes up to a tweeter. JBL also does that very well with their bigger speakers (old and new) and i think it has a lot to do with that their woofers are big, and are used over a wide range (for the 4367 from 30 to 700Hz) so the transients are largely intact. The crossover of that speaker to the tweeter is also very well done, so if the transients are higher than the crossover point they also stay intact.
You surely can do that also with several drivers in that band (sub and midbass) but they need to be aligned perfectly in time and phase and have a smooth transiton. The overtones are not made by the driver, they are reproduced by the driver. So yes, you can splitt them up in several bands.
The problem with many speakers is that the crossover is not good enough to get this result. Witth passive crossovers that is hard to do preceise enough, with dsp it became a lot easier i think.
The best kick sound i heared is with a (custom) sealed box with a woofer that goes low but goes up to a tweeter. JBL also does that very well with their bigger speakers (old and new) and i think it has a lot to do with that their woofers are big, and are used over a wide range (for the 4367 from 30 to 700Hz) so the transients are largely intact. The crossover of that speaker to the tweeter is also very well done, so if the transients are higher than the crossover point they also stay intact.
You surely can do that also with several drivers in that band (sub and midbass) but they need to be aligned perfectly in time and phase and have a smooth transiton. The overtones are not made by the driver, they are reproduced by the driver. So yes, you can splitt them up in several bands.
The problem with many speakers is that the crossover is not good enough to get this result. Witth passive crossovers that is hard to do preceise enough, with dsp it became a lot easier i think.
Then for example a purposeful FIR filtering would make them equal kicking? I doubt this would be possible in reality. A 26W/4558 can't do bass kick, you can't make a good hammer from a pillow.
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GD isn't always curable? When a resonance is tied to a long path length for example. You can only sync up the peak energy moment, but you can't always fix the amount of time it takes for the driver to reach peak energy. Instead of FR we are talking about compression. Compression also causes GD.
Group delay should be monotonically descending, avoiding peaks which indicate ringing. To do that, you may need to raise the tuning and possibly create a peak slight in the FR, as a side-effect of getting the GD right.
Compression causes group delay as well.... EQ cannot fix it. Compression is a non linear distortion.
A resonance thats caused by a long path length resonance has a time to peak energy that is directly tied to the SOS, EQ cannot fix that. With FIR you align peak energy. With minimum phase EQ you can remove GD and in the process, lose SPL which is why the GD is going away lol.
A resonance thats caused by a long path length resonance has a time to peak energy that is directly tied to the SOS, EQ cannot fix that. With FIR you align peak energy. With minimum phase EQ you can remove GD and in the process, lose SPL which is why the GD is going away lol.
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Okay, just buy a 26W/4558T00, make a same crossover (or best FIR filtering you can find) as the 4367 and done. Okay, the 26W have less than half the Sd of the 2216Nd-1 but the SS have about twice the Xmax of the JBL so max SPL is about equal in the bass range. Do you think they would sound the same? Haha (sorry!), just tell this to JBL...
Not identical but they seem to trace each other. Never the less. Peak energy Time.
"This can highlight variations in peak energy Arrival"
FR at one SPL isn't the only decider of GD is the point. In the case of compression, GD would increase with amplitude.
"This can highlight variations in peak energy Arrival"
FR at one SPL isn't the only decider of GD is the point. In the case of compression, GD would increase with amplitude.
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SPL may be equal, but look also about group delay and distortion, and smaller drivers tend to do that worse than big driver. They have advantages (go higher clean) but also disadvantages (less clean headroom). Kicks have high peaks in their transients and need huge headroom to be undistorted, and high power big cone drivers to that better. A 10" may be to small to really deliver that kick with all it's transients on a loud enough volume and with enough headroom before distortion kicks in. A rule that i heared somewhere is to count for +20dB headroom. So if you play average at 90dB/1m your speakers and amp should do a clean 110dB/1m to catch all those transients.
An other not mentioned issue is the power amp. To have a heavy hitting kick, your amp need to have enough headroom also. A low power tube amp will damp out the transient because the amp can't deliver the power need to the speaker to have those transient peaks. It's what most who love those amps want, But for a pucnhy hitting kick you better have a lot of peak power in reserve. That is one of the reasons that in pro audio they use amps that are often double the rating of the speakers connected, to have headroom to catch those transient peaks.
Group delay difference can be eliminated easily. As I said, the audible difference is there even at low SPL, where distortions is about the same/very low for both drivers.
If this is a car audio topic, then did you flick it. If you want a pressure wave, you want a stiff cone in a sealed box. Them cheap subs probably make some terrible noises in the higher frequencies, but are stiff. Often ribbed designs using hard plastic, which will never be found in home audio. Spend more and the SQ demands move away from them cone types, and sensitivity that will make them jump, just because you got in the car without anti-static socks on.
Designing a car system to thump, is a physical process. Chasing low F3's and smooth response, won't help. It's about energy. We are talking about feeling, not hearing. Porting can be an absolute disaster, because it can suck the bass out. Kick/punch is single piston action. If you put a ported box into another enclosure (the car/boot) then it's a bit like taking away the baffle. There is no resonance to tune the port with, it's just a hole. Cancellation is highly likely.
I don't avoid cone weight, just as long as I can move it, and stop it. That cone is coupled to the car, to me. E=MC2 and I want to feel it. The speed is fixed, but I can add mass, to add energy. From my amp.
Physical design considerations, beyond free air testing.
No, this isn't how I build house speakers either. Nor any other SQ based speaker. This is just thumping.
True 'Feel' is (of course) about vibrations rather than audible sound; in order to feel chest vibrations they must occur there. It has little to do with audiophile-type levels of sophistication (which relate to how our highly developed hearing can hear audible subtleties).
More significant chest vibration occurs (as with many things) at it's resonant frequency. The SPL needs to (of course) be sufficient, but because it is a resonance the effect is disproportionately large for the amount of energy at that frequency. Which includes increasing the effect of frequencies that might be attenuated due to roll-off. So a subwoofer with a bigger apparent audible impact may have less effect on our 'feel' than a more modest subwoofer with a shallower roll-off. Clearly this relates to the box design, not just the driver. Or a PA system with relatively high low-frequency roll-off can still have enough energy lower down to shake our bits.
That particular frequency will depend on the individual; proper whole-chest resonance is typically around 30hz for many. But of course there are numerous components within the human chest, which may be excited at different frequencies. IIRC frequencies up to around 85hz have been said to induce some kind of chest feel.. EDIT: It is not one single thing; if you have felt properly low and loud 'sounds' this is different (but complimetary to) feeling slightly higher frequency ones; below/beyond a certain level the feelings can include nausea and even be physically dangerous. Then there are questiions about whether it is just the chest or can the abdomen or other bits join the party?
However, whilst the tile of this thread includes 'science', like most threads of this nature it has immediately gone beyond known fact into conjecture and feelings etc. Partly because it is subjective and different people understand things like feel, attack, thump etc as meaning different things. I think it would be fair to say too, that in reality and in listening to real music things are almost always bundled together; we rarely only 'feel' chest kick, without also hearing something correspondingly loud in the ears. It may not even correspond directly; if I subjectively listened to music with feelable chest kick but with a bland reproduction of the snare drum, the overall feel would probably 'seem' to have much less kick in general, even though the snare does nothing (or less) to my chest.
More significant chest vibration occurs (as with many things) at it's resonant frequency. The SPL needs to (of course) be sufficient, but because it is a resonance the effect is disproportionately large for the amount of energy at that frequency. Which includes increasing the effect of frequencies that might be attenuated due to roll-off. So a subwoofer with a bigger apparent audible impact may have less effect on our 'feel' than a more modest subwoofer with a shallower roll-off. Clearly this relates to the box design, not just the driver. Or a PA system with relatively high low-frequency roll-off can still have enough energy lower down to shake our bits.
That particular frequency will depend on the individual; proper whole-chest resonance is typically around 30hz for many. But of course there are numerous components within the human chest, which may be excited at different frequencies. IIRC frequencies up to around 85hz have been said to induce some kind of chest feel.. EDIT: It is not one single thing; if you have felt properly low and loud 'sounds' this is different (but complimetary to) feeling slightly higher frequency ones; below/beyond a certain level the feelings can include nausea and even be physically dangerous. Then there are questiions about whether it is just the chest or can the abdomen or other bits join the party?
However, whilst the tile of this thread includes 'science', like most threads of this nature it has immediately gone beyond known fact into conjecture and feelings etc. Partly because it is subjective and different people understand things like feel, attack, thump etc as meaning different things. I think it would be fair to say too, that in reality and in listening to real music things are almost always bundled together; we rarely only 'feel' chest kick, without also hearing something correspondingly loud in the ears. It may not even correspond directly; if I subjectively listened to music with feelable chest kick but with a bland reproduction of the snare drum, the overall feel would probably 'seem' to have much less kick in general, even though the snare does nothing (or less) to my chest.
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Did you heard a live drum sound from close distance or from not too far? Everyone can recognize that kick in the chest.
Edit: but even from longer distance can be heard and felt.
It's true that the fundamental from such a kick is low, but if you filter the top (the transients and overtones) out of it it won't hit hard neighter. You need headroom in both and you need a even sound to have it.