I looked at Kimmosto's tuning for Taipuu 3 way speaker (https://taipuuspeakers.fi/en/taipuu-speakers-dsp-active-speakers/) and found the same kind of rising up directivity in the low frequencies as @fluid said. But here the overall system concept is a little different than mine
Then I tried playing around with the diffraction response-based 2x15inch driver responses once more to make the directivity (SPDI) rise than creating a plateau.. Here is a comparison between the results I posted yesterday vs the ones I got today
Directivity matching between DSP EQed 2 woofer sealed box system & EXAR 400 Waveguide from yesterday
Directivity matching between DSP EQed 2 woofer sealed box system & EXAR 400 Waveguide from today
To get the above result, I was trying to do the following things:
1) Sacrifice some amount of low-frequency SPDI to create a rising SPDI instead of a plateau
2) To do the above, make the two 15-inch woofers operate closer in phase with each other below 100ish Hz and make the phase responses diverge above 100Hz.
3) Trying not to give up the greater than 10dB of attenuation to the beyond 135 degrees of angle in the horizontal plane from somewhere close to 200Hz
4) While doing all the above, minimize the excess group delay to as small a value as possible, aiming for a target of excess group delay less than 2.2 ish ms at 100 Hz.
The resulting responses can be seen below
VituixCAD 6pack from today
EQ that created above responses
One of the things I realized from this exercise is that if the lower subwoofer driver has less inductance roll-off towards the high frequencies, it is easier/more flexible to tune the above kinds of responses. But then there might be a compromise of what driver one wants to use and its availability. For me the SB driver is easily available locally. Hence there is a strong motivation to get it..
Also, I am pretty sure the above responses can be changed for better looking (to the eyes) plots. But I am refraining from that now since there should be an end to this proof of concept tuning. Sometime I have to start getting to build the actual boxes and put drivers in them.. 😀
Out of curiosity I was wondering how an 18inch SB driver might do (locally available at less cost than the SB audience NERO SW800 I have used in the above simulations) in this system as the subwoofer driver.. 😉 😀 😀 But because of size constraints and overall height of the 2 boxes, I might have to get settled on a 15inc subwoofer I think....
Then I tried playing around with the diffraction response-based 2x15inch driver responses once more to make the directivity (SPDI) rise than creating a plateau.. Here is a comparison between the results I posted yesterday vs the ones I got today
Directivity matching between DSP EQed 2 woofer sealed box system & EXAR 400 Waveguide from yesterday
Directivity matching between DSP EQed 2 woofer sealed box system & EXAR 400 Waveguide from today
To get the above result, I was trying to do the following things:
1) Sacrifice some amount of low-frequency SPDI to create a rising SPDI instead of a plateau
2) To do the above, make the two 15-inch woofers operate closer in phase with each other below 100ish Hz and make the phase responses diverge above 100Hz.
3) Trying not to give up the greater than 10dB of attenuation to the beyond 135 degrees of angle in the horizontal plane from somewhere close to 200Hz
4) While doing all the above, minimize the excess group delay to as small a value as possible, aiming for a target of excess group delay less than 2.2 ish ms at 100 Hz.
The resulting responses can be seen below
VituixCAD 6pack from today
EQ that created above responses
One of the things I realized from this exercise is that if the lower subwoofer driver has less inductance roll-off towards the high frequencies, it is easier/more flexible to tune the above kinds of responses. But then there might be a compromise of what driver one wants to use and its availability. For me the SB driver is easily available locally. Hence there is a strong motivation to get it..
Also, I am pretty sure the above responses can be changed for better looking (to the eyes) plots. But I am refraining from that now since there should be an end to this proof of concept tuning. Sometime I have to start getting to build the actual boxes and put drivers in them.. 😀
Out of curiosity I was wondering how an 18inch SB driver might do (locally available at less cost than the SB audience NERO SW800 I have used in the above simulations) in this system as the subwoofer driver.. 😉 😀 😀 But because of size constraints and overall height of the 2 boxes, I might have to get settled on a 15inc subwoofer I think....
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This is true and why the idea worked OK for the driver I had to use which is a Dayton HF Reference 15". This is low inductance and the frequency response extends quite high. For the same reason I suggested the SB34. You will have to pick your poison if there is not a driver available that combines excellent volume displacement with decent frequency response above the normal subwoofer range.
You did a good job trying to get the directivity to rise. It isn't easy juggling all the parameters 🙂
I have no idea if either will sound very different from each other or if you will have a preference, but with an active system it will be easy enough to try them out and listen for yourself.
The question you will need to ask yourself is if you are willing to sacrifice 10dB of headroom (c.f twin forward firing woofers on the front panel)
Only you and your ears and listening preferences can decide on that.
If you keep your cabinet flexible, you may not be to decide now. You can adapt and change later.
build with confidence Vineeth! Fine tune later (you have PM)
Only you and your ears and listening preferences can decide on that.
If you keep your cabinet flexible, you may not be to decide now. You can adapt and change later.
build with confidence Vineeth! Fine tune later (you have PM)
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@tktran303: I am definitely going to put the woofers in two separate cabinets with the driver at the middle of each box. It allows the flexibility to experiment
So that I can always flip them around if needed.. 🙂
Having separate boxes with centered drivers might help with reduction in box resonance modes as well..
I am still not sure about the color scheme.. And I don't know if that ring around the top woofer might make it into a final build.. I request everyone to suggest some color scheme ideas.. 🙂
So that I can always flip them around if needed.. 🙂
Having separate boxes with centered drivers might help with reduction in box resonance modes as well..
I am still not sure about the color scheme.. And I don't know if that ring around the top woofer might make it into a final build.. I request everyone to suggest some color scheme ideas.. 🙂
@tktran303: Nowhere.. 😀
Drivers will be black anyway. But the 3D files from scanspeak doesn't allow me to change their color in fusion 😀
Drivers will be black anyway. But the 3D files from scanspeak doesn't allow me to change their color in fusion 😀
The drivers being discussed aren't both able to be used to cover the same frequency range on the front panel, so any loss of headroom is theoretical based on being able to use two drivers on the front across the full frequency range.
Having the sub driver go back to omni at around 100Hz means that below that frequency there is really no difference between the driver facing forward or backwards. The option is always there to forego any extra directivity control and just cross directly between the two drivers. Quite a few W371A owners seem to choose to do this.
Other than portability I don't see any real value in making the upper and lower boxes separate. It could easily turn out to be a problem if the lower sub causes the top box to dance around.
@tktran303: Regarding drivers
SB34NRXL: Not available for the last 1 year
RSS390: Not available since 2-3 years back
SB34NRXL: Not available for the last 1 year
RSS390: Not available since 2-3 years back
For Vineeth availability as he stated, the other reason would be that neither of those driver is usable much beyond 300 to 400Hz, where the 15PR400 is.
Another possible reason could be to avoid having large bass excursions modulate the lower midrange frequencies.
A great speaker could be made with two of those drivers facing forward (Jon Marsh's Isiris ) but it wouldn't be quite the same or as flexible as what was being discussed.
Too bad the Dayton is not avaliable in India or more expensive than SB Acoustic in Europe. 85 sealed was good for a 15" and enough low end for hifi.
Why not trying band pass design for the bass with the low pass part around 100 to 150 hz ? The further upper ripple can be notched active. It can fire on the back while you cardioid à la 8C the midwoof front driver ?
Too much complex ?
I would study the Boston acoustic 500l bass cabinet. It rocks and let the acoustic cross around 100 hz with a second order damped low pass electrical if i am correct plus the mechanical low pass of the band pass : steep slope, no much modulation on the upper midwoof driver.
If a band pass can also been made vented why not lossy cardioid way as well.
Why not trying band pass design for the bass with the low pass part around 100 to 150 hz ? The further upper ripple can be notched active. It can fire on the back while you cardioid à la 8C the midwoof front driver ?
Too much complex ?
I would study the Boston acoustic 500l bass cabinet. It rocks and let the acoustic cross around 100 hz with a second order damped low pass electrical if i am correct plus the mechanical low pass of the band pass : steep slope, no much modulation on the upper midwoof driver.
If a band pass can also been made vented why not lossy cardioid way as well.
Tip: plenty bass automotiv bass drivers with low Vas in India. Take two per cabinet. 6" to 8". No problème with class D.
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I really like this kind of finishing/color scheme 😀 (My wife likes it too.. 😉 )
I might go with this..
I might go with this..
Yes agreed.
I thought that the white drivers and white side panels were err…
Meanwhile the black side panels are more slimming…
I thought that the white drivers and white side panels were err…
Meanwhile the black side panels are more slimming…
So the beasts have arrived home (I bit the bullet and got the SB audience NERO SW800.. 🤓)..
I am supposed to have got it here for the best price in the whole world including shipping (according to the dealer)
Only once it reached home (very quickly), I realized that there is a substantial amount of "driver" in there.. About 20kgs of "it" per box.. 😲😲
I don't understand why it is so heavy 🤔
Being used to the weight of the Faital pro15PR400 (very lightweight), I accidentally tried to get the driver in one hand and barely escaped getting myself, and the driver hurt.. 😳
I can imagine this will be some work the day I try to take measurements and move the system (whenever and whatever that is) to its final place..
Till then, maybe I should try to focus on building some muscle.. 🤔🤓
I am supposed to have got it here for the best price in the whole world including shipping (according to the dealer)
Only once it reached home (very quickly), I realized that there is a substantial amount of "driver" in there.. About 20kgs of "it" per box.. 😲😲
I don't understand why it is so heavy 🤔
Being used to the weight of the Faital pro15PR400 (very lightweight), I accidentally tried to get the driver in one hand and barely escaped getting myself, and the driver hurt.. 😳
I can imagine this will be some work the day I try to take measurements and move the system (whenever and whatever that is) to its final place..
Till then, maybe I should try to focus on building some muscle.. 🤔🤓
I also wonder, what is that thing I see inside the mesh.. 🤔
and why my driver doesn't have the nice pattern like there is in Joseph Crowe's testing pics..🤔
and why my driver doesn't have the nice pattern like there is in Joseph Crowe's testing pics..🤔
If you are talking about the response ripples below 100 Hz, they are floor responses from their measurement on an IEC baffle.
Compare that data sheet to their 15OB350 - they are almost exactly the same.
Do a ground plane or a close-mic measurement of the drivers and they will be much smoother!
Compare that data sheet to their 15OB350 - they are almost exactly the same.
Do a ground plane or a close-mic measurement of the drivers and they will be much smoother!