Hi 3wayaddict,
This time i'm gonna have some thoughts about your overall design choices.
One thing bother me in the fact that you use 2 group of three speakers for low mid (100hz to 400hz).
I fully understand your point about membrane surface but this kind of vertical arrangement will probably lead to issues with directivity(vertical).
If you want acoustic coupling of speakers you should stay within 1/4 wavelength (at fc) C to C spacing and i fear this would not be the case on the whole range they'll have to reproduce. You talked about linearray previously but for my understanding, line array doesn't match fairly well with a point source approach ( which is the raison d'etre of MTM in my view). Either you go full into line array either you go full point source, not sure you can mix both ( at least i've not seen anything like that).
That said, mtm or mmtmm are pretty effective to minimize floor bounce ( which happen in the 150/300hz area where the drivers will be effective), don't know for something like you plan, i'll have to simulate that to have an idea of what'll results.
Have you lived long term with good designed MtM? Some people dislike the rendering ( i like it when correctly done!).
Another observation about the fc for sub/low and low mid: why did you choose 100hz and 400hz? What is your line of thoughts about that?
For me 100hz is not an optimal choice: if you look at satelitte +sub approach it is often 80hz as sat to sub fc. This is because most first harmonics of low instruments are located around that freq ( and our brain is able to reconstruct the missing fundemental from there). This give an 'almost' full range from sat and give the 'hard' work to sub. From my experience you'll gain in coherency. It is usually considered that there is much less directivity info below 80hz ( in fact i think indoor this is more related to next point).
An other approach could be to integrate your room into this: schroeder frequency of your room will determine modal behavior where the room takes over your loudspeaker. If your room is small this could happen as high as 200hz, if big it could be 100hz or slightly lower.
As you plan some kind of distributed low why not take advantage of this and locate fc at that point of schroeder freq?
This time i'm gonna have some thoughts about your overall design choices.
One thing bother me in the fact that you use 2 group of three speakers for low mid (100hz to 400hz).
I fully understand your point about membrane surface but this kind of vertical arrangement will probably lead to issues with directivity(vertical).
If you want acoustic coupling of speakers you should stay within 1/4 wavelength (at fc) C to C spacing and i fear this would not be the case on the whole range they'll have to reproduce. You talked about linearray previously but for my understanding, line array doesn't match fairly well with a point source approach ( which is the raison d'etre of MTM in my view). Either you go full into line array either you go full point source, not sure you can mix both ( at least i've not seen anything like that).
That said, mtm or mmtmm are pretty effective to minimize floor bounce ( which happen in the 150/300hz area where the drivers will be effective), don't know for something like you plan, i'll have to simulate that to have an idea of what'll results.
Have you lived long term with good designed MtM? Some people dislike the rendering ( i like it when correctly done!).
Another observation about the fc for sub/low and low mid: why did you choose 100hz and 400hz? What is your line of thoughts about that?
For me 100hz is not an optimal choice: if you look at satelitte +sub approach it is often 80hz as sat to sub fc. This is because most first harmonics of low instruments are located around that freq ( and our brain is able to reconstruct the missing fundemental from there). This give an 'almost' full range from sat and give the 'hard' work to sub. From my experience you'll gain in coherency. It is usually considered that there is much less directivity info below 80hz ( in fact i think indoor this is more related to next point).
An other approach could be to integrate your room into this: schroeder frequency of your room will determine modal behavior where the room takes over your loudspeaker. If your room is small this could happen as high as 200hz, if big it could be 100hz or slightly lower.
As you plan some kind of distributed low why not take advantage of this and locate fc at that point of schroeder freq?
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Okay, will stick to the 32W then.
I was already afraid the flat-wave-effect like that of a line source might be hard to obtain with a setup like this in mid bass. So I was already thinking of making the shape of the cabinet adjustable, like with the Focal Utopia and Wilson Audio speakers. This way you can aim the drivers exactly at the listening position at perfect equal distances, like drawing a cirkel of drivers with the right diameter around the listening position. This will give perfect time-alignment. Then, when not going for something like a line source anyway, I could also use four of the bigger W26FX001s in case of the Seas Excel drivers. Because you guys seem to get pretty mad at me for not believing smaller drivers with the exact same Sd yet higher motor/Sd ratio will sound as good but will be quicker.
In casenof the Accuton drivers it will stay with six C220-6-222s since there's no bigger model anyway.
I was already afraid the flat-wave-effect like that of a line source might be hard to obtain with a setup like this in mid bass. So I was already thinking of making the shape of the cabinet adjustable, like with the Focal Utopia and Wilson Audio speakers. This way you can aim the drivers exactly at the listening position at perfect equal distances, like drawing a cirkel of drivers with the right diameter around the listening position. This will give perfect time-alignment. Then, when not going for something like a line source anyway, I could also use four of the bigger W26FX001s in case of the Seas Excel drivers. Because you guys seem to get pretty mad at me for not believing smaller drivers with the exact same Sd yet higher motor/Sd ratio will sound as good but will be quicker.
In casenof the Accuton drivers it will stay with six C220-6-222s since there's no bigger model anyway.
Im not sure about few(one?) big or more smaller woofers, but one experienced guy asked me to think about knocking my fist as hard/fast as I could thruu the air. Most of the air would just slip past as fist cut through. whereas as closing a light wellfitted door lightly will let you feel the pressure in the room. Also think about pebbles in water. Try heavy smaller objects in water and then light larger object and observer the ripples
Bigger drivers also usually have bigger motor and Xmax (and Vd).
They also usually have a lower Fs (this means they are "slower", but only when playing slower frequency).
But you must not move your head.
I listened to this, but they sounded like headphones (which I really dislike) and if you move head just a bit, lobbing begins.
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In my mind, line arrays seems to be the ultimate design, ”infinite” lines from floor to ceiling like roger russells ids-25 but with s-s 10f or better is my dream, i have never heard one but i can imagine it will blow my pants of and how i faint by pleasure
But you must not move your head.
I listened to this, but they sounded like headphones (which I really dislike) and if you move head just a bit, lobbing begins.
They probably sounded like headphones because it's an array of drivers all aimed at one point, but with all full range drivers.
I made something like this (9 x 4" focused array), you sit 1' in front of the focus.
Much larger vertical sweet spot than my 4 x 4" focused array.
It sounded really good everywhere (near, far, sit, stand), but best at sweet spot.
Really lights up a room with sound, but sound seemed to come from the middle 3 drivers.
And width of dispersion depends on cone size, so a 4" did couch wide at 8'.
Headphone like, yes, but the image is in front of you, not in your head.
Were i not into my jbl's, solstice, or needing beat you up midbass, I wouldn't hesitate to build another.
If anyone has questions on focused arrays, please email me here, so you do not repeat my mistakes.
A great option for people into time alignment or full range drivers (crossover phase sensitive 6db people too !).
Norman
Much larger vertical sweet spot than my 4 x 4" focused array.
It sounded really good everywhere (near, far, sit, stand), but best at sweet spot.
Really lights up a room with sound, but sound seemed to come from the middle 3 drivers.
And width of dispersion depends on cone size, so a 4" did couch wide at 8'.
Headphone like, yes, but the image is in front of you, not in your head.
Were i not into my jbl's, solstice, or needing beat you up midbass, I wouldn't hesitate to build another.
If anyone has questions on focused arrays, please email me here, so you do not repeat my mistakes.
A great option for people into time alignment or full range drivers (crossover phase sensitive 6db people too !).
Norman
Yes, it is not exactly like headphones.
Anyway I didn't like them, but than again I listened them just for a few minutes.
Versions with four mid woofers. In the case of four mid woofers the W26FX001 does seem like a good option. If that impulse response relative to Sd and excursion is true, which I believe you in it is, the is still copes with the smaller drivers. Anyway when comparing four W26s to four W22s the W26 obviously have a way bigger Sd and also much bigger Xmax, and they go much lower by themselves. And F3 of 41 Hz in a sealed box in simulation! So in case of a design with four mid woofers I do think the X26s are the right choice.
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And a new design of the bass towers. They are a bit wider and deep than the initial design, though they now feature two drivers per module mounted in opposite directions for vibration canceling. Vibrations with such a high structure with such many big drivers would have become quite bad.
Also, even with the huge feet under them one of these modules isn't as tall as two of the previous modules. The huge feet are to make the slots between two modules as big as the surface area of the two woofers.
Also, even with the huge feet under them one of these modules isn't as tall as two of the previous modules. The huge feet are to make the slots between two modules as big as the surface area of the two woofers.
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Loudspeaker designs typically start with a list of performance goals and constraints that must be satisfied. From this the basic driver configuration is chosen and only then specific drivers are picked.
I suggest you do not rush the designing proces and start at the beginning.
I suggest you do not rush the designing proces and start at the beginning.
Here the goal is best posible sound from some choises of configurations i believe. Constraints will be a room with sealing, floor and minimum 2 corners. Endresult wont nessesarily be realised beyond being designed.
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Leave the Arcosia drivers, the models in the line just don't fit this concept. Those 4" midranges, honestly I just find too small. I doubt if they will have any body to them, they might be more useful in a four way concept where there is a lower and higher midrange. And the 7" isn't really useful at all. Like any magnesium mid woofer of the size it's only useable to 1,5~1,7 kHz at highest. It should be very good as amid woofer but not here because we are looking to use bigger woofers.
The Symphony II woofers however seem very capable. I don't doubt they have very low distortion and all and though their size they are blazingly quick. However, I personally don't like poly cones. So I looked at something of it's size that performs similar but with a metal cone. I came to the Scan-Speak Revelator 26W/8867T00. It's a metal cone so it should offer the sound characteristic I want at it should blend well with the hard cone midrange. And it's blazingly quick. *** fast as the 11" Eton woofer and certainly faster than the Seas Excel woofers. It has a bigger Xmax and so more linear excursion than the W26FX001 and it will certainly have lower distortion as well. Because that't the only main problem I have with the bigger Excel woofers, they aren't that quick compared to what else is on the market. The Scan-Speak should beat it in any way.
The Symphony II woofers however seem very capable. I don't doubt they have very low distortion and all and though their size they are blazingly quick. However, I personally don't like poly cones. So I looked at something of it's size that performs similar but with a metal cone. I came to the Scan-Speak Revelator 26W/8867T00. It's a metal cone so it should offer the sound characteristic I want at it should blend well with the hard cone midrange. And it's blazingly quick. *** fast as the 11" Eton woofer and certainly faster than the Seas Excel woofers. It has a bigger Xmax and so more linear excursion than the W26FX001 and it will certainly have lower distortion as well. Because that't the only main problem I have with the bigger Excel woofers, they aren't that quick compared to what else is on the market. The Scan-Speak should beat it in any way.
Symphony II isn't really a poly-cone. Sort of a kevlar-skin with resin over a structural honeycomb (..which is likely some sort of poly). The sound isn't like a "poly" driver at all. Motor structure for most of their driver range though isn't the greatest though (though the 3" version may well be based on their excellent motor).
You might want to look closer at these:
Dayton Audio Drivers - EPIQUE by Dayton Audio
You might want to look closer at these:
Dayton Audio Drivers - EPIQUE by Dayton Audio
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Oh yeah those. They're literally the Accuton C220-6-222 without the grill with a carbon Fiber cone. AudioXpress has measurements of the 5-1/4" model. They seem quite good. In terms of speed, obviously, they're the best on the market because of the fact they're just reconed Accuton's. They seem to go low enough for the crossover as well. They seem pretty good, though I don't know about the sound of the carbon fiber cones, and even though it's an Accuton motor and basket with just a different cone, does anyone know how they sound? Do they actually sound good as well?
And why should I get these over the Accuton? It's literally the same but with a carbon fiber cone.
And why should I get these over the Accuton? It's literally the same but with a carbon fiber cone.
For a configuration with metal cones. I actually think six Scan-Speak Revelator 22W/8857T00 should be amazing. Yes it's three drivers again and it's 8" instead of 10" but hear me out.
The 26W is quicker than the Seas Excel W26FX001. It's the fastest 10" I know of. It has a Sd of 320 cm2 and a Xmax of 9 mm. Then, the 22W, because it's slightly smaller, it is even slightly faster. And yes it is smaller but. It has a Sd of 220 cm2 and also a Xmax of 9 mm. So if you take six W22s vs four 26Ws. You actually have 40 cm2 more Sd than the 26Ws, so they have to move slightly less to move a given volume of air AND because they have the same Xmax, they make this movement just as linear and easy as the 26Ws would. AND because they are slightly smaller they already are slightly faster of themselves. So they are faster AND don't have to move as much. Seems like a winner to me.
The 26W is quicker than the Seas Excel W26FX001. It's the fastest 10" I know of. It has a Sd of 320 cm2 and a Xmax of 9 mm. Then, the 22W, because it's slightly smaller, it is even slightly faster. And yes it is smaller but. It has a Sd of 220 cm2 and also a Xmax of 9 mm. So if you take six W22s vs four 26Ws. You actually have 40 cm2 more Sd than the 26Ws, so they have to move slightly less to move a given volume of air AND because they have the same Xmax, they make this movement just as linear and easy as the 26Ws would. AND because they are slightly smaller they already are slightly faster of themselves. So they are faster AND don't have to move as much. Seems like a winner to me.
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