I made this illustration for another thread but I have explored this here earlier too.
I noticed that my 4" cone mid does not behave like a simulated planar dipole when we go to 60¤ and beyond off-axis. Instead of shifting dipole peak up, it comes down! my explanation to this is that a cone radiates differently off-axis than a plane or point source. I got supprot to this from a Klippel paper
Here are Siegfried Linkwitz and John Kreskowsky telling about dipole radiation. The model is based on a plane source.
Here is a collashe of OllBoll's, SL's and my measurements showing this oddity off-axis.
Attachment is my hand-drawn illustrations about what I see happening.
I am so eager to get new baffles to mount Neo8s to "AINOgradient Neo" This is how it plays off-axis. Smack dab in the middle of simulations!
I noticed that my 4" cone mid does not behave like a simulated planar dipole when we go to 60¤ and beyond off-axis. Instead of shifting dipole peak up, it comes down! my explanation to this is that a cone radiates differently off-axis than a plane or point source. I got supprot to this from a Klippel paper
Here are Siegfried Linkwitz and John Kreskowsky telling about dipole radiation. The model is based on a plane source.
Here is a collashe of OllBoll's, SL's and my measurements showing this oddity off-axis.
Attachment is my hand-drawn illustrations about what I see happening.
I am so eager to get new baffles to mount Neo8s to "AINOgradient Neo" This is how it plays off-axis. Smack dab in the middle of simulations!
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hi Juhazi,
the Neo 8 without box & baffle can't be crossed below~1500 hz ? Wha about the 12 " : up to 1000 hz maxi ?!
What about : Neo 10 : 300 LR2 to ~ 1900 the NEO8s to ~5000 hz then your fountek LR4 or B&G Neo 3 ? But the proble of Neo 10 below 1000 hz without large bafle ????
My 2 cents collaborative...
the Neo 8 without box & baffle can't be crossed below~1500 hz ? Wha about the 12 " : up to 1000 hz maxi ?!
What about : Neo 10 : 300 LR2 to ~ 1900 the NEO8s to ~5000 hz then your fountek LR4 or B&G Neo 3 ? But the proble of Neo 10 below 1000 hz without large bafle ????
My 2 cents collaborative...
"the Neo 8 without box & baffle can't be crossed below~1500 hz ?"
How come? It doesn't need much eq to match LR4 at 800Hz. Distortion? Do you have a link to measurements?
B&G original datasheet says PDR can be crossed 400-500Hz LR2. Datasheet measurements are without eq. My measurements did not show any problem with distortion or csd (posted a month ago).
How come? It doesn't need much eq to match LR4 at 800Hz. Distortion? Do you have a link to measurements?
B&G original datasheet says PDR can be crossed 400-500Hz LR2. Datasheet measurements are without eq. My measurements did not show any problem with distortion or csd (posted a month ago).
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I made this illustration for another thread but I have explored this here earlier too.
I noticed that my 4" cone mid does not behave like a simulated planar dipole when we go to 60¤ and beyond off-axis. Instead of shifting dipole peak up, it comes down! my explanation to this is that a cone radiates differently off-axis than a plane or point source. I got supprot to this from a Klippel paper
Here are Siegfried Linkwitz and John Kreskowsky telling about dipole radiation. The model is based on a plane source.
Here is a collashe of OllBoll's, SL's and my measurements showing this oddity off-axis.
Attachment is my hand-drawn illustrations about what I see happening.
I am so eager to get new baffles to mount Neo8s to "AINOgradient Neo" This is how it plays off-axis. Smack dab in the middle of simulations!
Keep in mind that my measurement is of 90-180 of a driver with a very large an obstructing magnet.
The 700 hz dip is an issue with the driver and has been observed elswhere too. The big dips and erratic response above 2 khz is probably more due to the magnet than of dipole peak behaviour. If it was dipole behaviour the front dispersion would have the same issues but it doesn't, at least not in 0-60 degrees:
Measurements of the driver by the manifacturer AE:
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hi,
No I don't talk about distorsion masurement but your simulation which show a poor low-end in term of DB level below 1K ; 1,5 K hz.
+ the use of it without bafle in your design à la Gradiant (Prefer the Boulle School), my understanding reading your sim is that you can't use it without a big dip below someting 1,5 to 2 K hz XO. Am I wrong ?
Think, the data of B&G are for a very near listening distance and measurement, maybe I'm wrong. Here is a measurement made on his litle brother The Neo8. The S serie is better in low end but still have the same problem of weak curve below around 1000 hz. But maybe here the +3 db predicted by John K in the ~100 to 900 hz help.
In fact this is a question of me, which technique would you use with the Neo 8 s to lift the curve below 1 khz without bafle and box ? EQ ? So distorsion, not sure a planar support a strong EQ like that.
Maybe I have been missanderstanding something about the previous posts, but in my mind the 12" can't go above 1000 in OB without problem of smoothing off axis response.
That's why I wrote about the Neo 10 + Neo 8s with theorical XO given... very interested with your work and the one of Studiotech...Zmyrna (they use the Neo 8s in a sealed box)
Many said the NEO3 PDR is a gem above 5k or 7 k, not really below, same with Neo 10 far better < 2 khz, but some like Greg use it at 3K; Same with Neo 8S, good above 600 hz but problem of spl curve below 1000 hz : many see it like a good mid tweeter between 1K to 5K, some people use it above with strong EQ beginning above 1000 because they saw that the ringings in the higher spl curve was the periodic repitition on a peak below, so XO at > 1 khz avoid a lot of energy peaks in the high end and minimize EQ. In this condition the Neo8S become a good solution to avoid filter in the critical 1K to 8 K hz.
Can you explain me, this a terrible dilemna to me How to have a good fast light mid bass with a dipole between 100 hz to the upper driver (300 or 600 hz max). I really think this aera is critical. I woulg go for the 26LROY below 100 hz in a closed box but above ? The Beyma... too heavy mms is my opinion for this critical aera which need to be very controled... the Audax PR17...Z0 with its 10 g mms and 100 DB SPL/1W/1m does not exist anymore !
So a 3 active ways with dipole or a OSWG with CD > 1000 hz with dipole midrange ? The narrow path is splitting in two direction for me and I'm lost
.
No I don't talk about distorsion masurement but your simulation which show a poor low-end in term of DB level below 1K ; 1,5 K hz.
+ the use of it without bafle in your design à la Gradiant (Prefer the Boulle School), my understanding reading your sim is that you can't use it without a big dip below someting 1,5 to 2 K hz XO. Am I wrong ?
Think, the data of B&G are for a very near listening distance and measurement, maybe I'm wrong. Here is a measurement made on his litle brother The Neo8. The S serie is better in low end but still have the same problem of weak curve below around 1000 hz. But maybe here the +3 db predicted by John K in the ~100 to 900 hz help.
In fact this is a question of me, which technique would you use with the Neo 8 s to lift the curve below 1 khz without bafle and box ? EQ ? So distorsion, not sure a planar support a strong EQ like that.
Maybe I have been missanderstanding something about the previous posts, but in my mind the 12" can't go above 1000 in OB without problem of smoothing off axis response.
That's why I wrote about the Neo 10 + Neo 8s with theorical XO given... very interested with your work and the one of Studiotech...Zmyrna (they use the Neo 8s in a sealed box)
Many said the NEO3 PDR is a gem above 5k or 7 k, not really below, same with Neo 10 far better < 2 khz, but some like Greg use it at 3K; Same with Neo 8S, good above 600 hz but problem of spl curve below 1000 hz : many see it like a good mid tweeter between 1K to 5K, some people use it above with strong EQ beginning above 1000 because they saw that the ringings in the higher spl curve was the periodic repitition on a peak below, so XO at > 1 khz avoid a lot of energy peaks in the high end and minimize EQ. In this condition the Neo8S become a good solution to avoid filter in the critical 1K to 8 K hz.
Can you explain me, this a terrible dilemna to me How to have a good fast light mid bass with a dipole between 100 hz to the upper driver (300 or 600 hz max). I really think this aera is critical. I woulg go for the 26LROY below 100 hz in a closed box but above ? The Beyma... too heavy mms is my opinion for this critical aera which need to be very controled... the Audax PR17...Z0 with its 10 g mms and 100 DB SPL/1W/1m does not exist anymore !
So a 3 active ways with dipole or a OSWG with CD > 1000 hz with dipole midrange ? The narrow path is splitting in two direction for me and I'm lost
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I have measured Neo8-PDR dipole response from 200Hz up and it has almost as low distortion as Audax HM100Z0, according to my preliminary tests. Vifa NE95-w distorts much more but I have two of them in series. Now we must wait a little before I can fit Neo8 in the new baffle. Then I'll perform new set of measurements, that are fully comparabe to present system.
I use minidsp for AINO. I don't use level gain above 0dB except below highpass, to avoid digital clipping/distortion. Because of dipole correction 6dB/octave any driver is challenged. However Neo8 has much smoother response than circular drivers as dipole, so it does not need that much eq. Neo8 has better efficiency than NE95 but less than Audax. Audax is too wide to be used dipole above 2kHz. (see my posts from late October)
Translated from German, test of Neo8. Klirrfaktor = distortion "Very low distrtion from 500Hz up (green level) and record-level low distortion from 1000Hz up"
Neo8S has best efficiency and lowest distortion. Neo8-PDR version has damping material on the most lateral area of the membrane, this is to make it acoustically smaller and to give better high end response. This is exactly what I need. LR4 at 800Hz should not be a problem, LR2 might be - at least it is for NE95s.
I use minidsp for AINO. I don't use level gain above 0dB except below highpass, to avoid digital clipping/distortion. Because of dipole correction 6dB/octave any driver is challenged. However Neo8 has much smoother response than circular drivers as dipole, so it does not need that much eq. Neo8 has better efficiency than NE95 but less than Audax. Audax is too wide to be used dipole above 2kHz. (see my posts from late October)
Translated from German, test of Neo8. Klirrfaktor = distortion "Very low distrtion from 500Hz up (green level) and record-level low distortion from 1000Hz up"
Neo8S has best efficiency and lowest distortion. Neo8-PDR version has damping material on the most lateral area of the membrane, this is to make it acoustically smaller and to give better high end response. This is exactly what I need. LR4 at 800Hz should not be a problem, LR2 might be - at least it is for NE95s.
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I just said that I don't use gain to correct for dipoel dip. But I forgot to say that instead I use attenuation to correct it!
Correction slope crosses 0dB at highpass F and attenuates above it according to measured response (reversed), the resulting sum is 0dB constant measured spl (well almost) between xo points and some range beyond them, to get by-book xo slopes (a mix of LR and ellipsoid)
Like this earlier posted pic of some version. Minidsp makes it possible to change slopes and xos easily and with no extra cost!
Correction slope crosses 0dB at highpass F and attenuates above it according to measured response (reversed), the resulting sum is 0dB constant measured spl (well almost) between xo points and some range beyond them, to get by-book xo slopes (a mix of LR and ellipsoid)
Like this earlier posted pic of some version. Minidsp makes it possible to change slopes and xos easily and with no extra cost!
Thanks Juhazi.
On the SPL curve I see ~10 db loss between 800hz and 2 Khz ? + the dipole loss, no EQ, no baffle, I am anable to understand how you can flat the Neo8 ? You pad off the high curve to put it at the level of the low one and then with the tweeter ? This is why why I questioned you. Maybe i will understand after you sow the design tested with neo 8 and others drivers.
I suppose that without EQ above 0 db for a driver, we can ajust the global DB of each amp to align the drivers each others or play with the needs or M-Fletcher curve... for example + 3 db below 150 or 200 hz in relation to the next driver above (>200 hz) whic is amplified at theorical 0 db ?? that why i want to go with active too : playing with the design and the spl of the drivers in relation to each others.
For Audax I was talking about an old driver the PR17H00Z0, but doesn't exist anymore.
I will wait for your empirical experiment with the Neo 8... Very interisting work you make.
I just happened to have that Audax! When I ordered it I hoped that I could use it in AINOgradient. It is a very special midrange, a legendary Aerogel, again in production.
Minisdp 4x10Hd or 2x8 gives freedom to use drivers with problematic curves and unequal efficiencies. User can set spl level, xos, many eqs, delay and polarity for each output channel, in my case 2x4. In addition user can set 5 peqs for each input channel (L/R) UI-software (plu-in) is very easy. Minidsp has revolutionized diy-audio! Problem is need of many amplifiers and one must be very careful to not accidentally switch it on/off while amps are on - it gives a huge pop-pulse!
Minisdp 4x10Hd or 2x8 gives freedom to use drivers with problematic curves and unequal efficiencies. User can set spl level, xos, many eqs, delay and polarity for each output channel, in my case 2x4. In addition user can set 5 peqs for each input channel (L/R) UI-software (plu-in) is very easy. Minidsp has revolutionized diy-audio! Problem is need of many amplifiers and one must be very careful to not accidentally switch it on/off while amps are on - it gives a huge pop-pulse!
I checked the distortion of B&G Neo8-PDR vs. Audax HM100Z0 both as dipole and just handheld at 1m to mic. IR gating is 9ms in spl graphs. Measured without any eq or xo, range 300Hz-22000Hz.
Both have low distrotion but Neo8 is much better. Neo8 needs less eq to bo crossed at 800Hz. Neo8's dipole peak is higher than Audax. Both have very smooth but different off-axis behaviour (not shown here) because of their different dimensions.
Both have low distrotion but Neo8 is much better. Neo8 needs less eq to bo crossed at 800Hz. Neo8's dipole peak is higher than Audax. Both have very smooth but different off-axis behaviour (not shown here) because of their different dimensions.
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5 ways ?
beyma 90 to 350hz then Neo 10 to 1900 hz then NEO 8 to 7k then NEO3 (5 ways) ? Or Beyma 100 to 1000hz then Neo 10 1000 to 1900hz ?
Or Beyma to 1200 (above that: off axis issues?) then the Neo 8 ? But the pit ! You will need strong EQ...or use the 12" Beyma with beaming if above 1200 hz...
Hope your first test before Cristmass with the Neo 8.
beyma 90 to 350hz then Neo 10 to 1900 hz then NEO 8 to 7k then NEO3 (5 ways) ? Or Beyma 100 to 1000hz then Neo 10 1000 to 1900hz ?
Or Beyma to 1200 (above that: off axis issues?) then the Neo 8 ? But the pit ! You will need strong EQ...or use the 12" Beyma with beaming if above 1200 hz...
Hope your first test before Cristmass with the Neo 8
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Eldam, I am very confident about my success with Neo8 800Hz - 4000Hz. Test baffle measurements of directivity are reliable (post #348) . Looks like my laser-cutter guy is busy.
I got the new acrylic frame plates today! Delivered to my hand still warm from cutting! And smelly!
New frames will replace the MTM frames seen in teh first picture. Attached with three screws to the pole supporting 12" driver.
Logo is engraved on the front side. I must install tweeter horns on top to avoid edge diffractions. Neo8 goes to the backside. I don't have M4 bolts and nuts at home now and I have a busy evening tomorrow. Measurements can be expected on friday evening or saturday. Perhaps the sound will be transparent too?
New frames will replace the MTM frames seen in teh first picture. Attached with three screws to the pole supporting 12" driver.
Logo is engraved on the front side. I must install tweeter horns on top to avoid edge diffractions. Neo8 goes to the backside. I don't have M4 bolts and nuts at home now and I have a busy evening tomorrow. Measurements can be expected on friday evening or saturday. Perhaps the sound will be transparent too?
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Neo8-PDR replaces double Vifa NE95W-04, MTM becomes MT with c-c distance 150mm. Fountek NEoCD3.5H will remain as tweeter. The thickness of acrylic is 6mm. Width is 100mm/90mm
Edge simulation of Neo8 in 90mm baffle. Good match with my measurements in test baffle. Suggested xos 800Hz LR4 and 4000Hz LR8 (acoustic)
Yes Eldam, the aircraft grade birch plywood 2x4mm with tung oil coating looks fantastic. But it is expensive- a carpenter's unique handwork! Sad to throw it away really...
Edge simulation of Neo8 in 90mm baffle. Good match with my measurements in test baffle. Suggested xos 800Hz LR4 and 4000Hz LR8 (acoustic)
Yes Eldam, the aircraft grade birch plywood 2x4mm with tung oil coating looks fantastic. But it is expensive- a carpenter's unique handwork! Sad to throw it away really...
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The visual MTM with the Vifas's Peereless are pretty too...
If they are the 4" Platinium line, I would asking myself to a 150 hz to 2 k hz... in a closed box.
I'm very eager to see the result of the Neo 8... I think it's a good way to go about the XO. I'm lookink for driver able to run 1000 k hz to 7 K hz... they are few... and all with a poor efficienty around 85 db or less !
No news from Zmyrna, did he give up its sealed box with Neo 8...?!
If they are the 4" Platinium line, I would asking myself to a 150 hz to 2 k hz... in a closed box.
I'm very eager to see the result of the Neo 8... I think it's a good way to go about the XO. I'm lookink for driver able to run 1000 k hz to 7 K hz... they are few... and all with a poor efficienty around 85 db or less !
No news from Zmyrna, did he give up its sealed box with Neo 8...?!
Bad news first - I broke 2 of 4 acrylic frame panesl during my fist test. Polycarbonate will be new material, but it must be cnc'd I guess. Laser cutting lead sto burned/melted edges.
Good news, excellent measured results for AINOgradient Neo ! Low distortion and constant directivity when used below dipole null. Neo8-PDR was crossed 800Hz LR4 / 4000Hz LR8.
Only 0, 30, 60 and 90¤ measured now. Not listened at all yet. 4kHz area is too hot, LR4 4500Hz might be ok with some peq individually for Neo8 and NeoCD3.5H
Notice! Response below 500Hz is plaqued with reflections, indoor measurements!
Good news, excellent measured results for AINOgradient Neo ! Low distortion and constant directivity when used below dipole null. Neo8-PDR was crossed 800Hz LR4 / 4000Hz LR8.
Only 0, 30, 60 and 90¤ measured now. Not listened at all yet. 4kHz area is too hot, LR4 4500Hz might be ok with some peq individually for Neo8 and NeoCD3.5H
Notice! Response below 500Hz is plaqued with reflections, indoor measurements!
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thanks for measurement. One day you explain to me how you calculate or choose the LP XO of an OB driver in relation to its size
I believe from my own taste that 4k to 5k hz bump will give you maybe some problems.... You maybe pad down the tweeter with 2 to 4 db ? Or an EQ to dig this aera (3k to 5 k hz).
Have myself yesterday a great improvement with a passive notch band pass at 4000 hz - 4db with my main speakers (measurement at 3,5 meters, listening position). before at 5k to 7k.
Birch ply is far more beautifull than transparent materials, just MHO.
I believe from my own taste that 4k to 5k hz bump will give you maybe some problems.... You maybe pad down the tweeter with 2 to 4 db ? Or an EQ to dig this aera (3k to 5 k hz).
Have myself yesterday a great improvement with a passive notch band pass at 4000 hz - 4db with my main speakers (measurement at 3,5 meters, listening position). before at 5k to 7k.
Birch ply is far more beautifull than transparent materials, just MHO.
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Noticed how close the mounting holes are the the frame edge. Very fracture prone area.
Lovely curves, have you considered flipping the panel so the tweeter is on the bottom?