First was just unusually low Qes for what it is. An educated guess. That confirmed that when I put the data into Hornresp, the Bl was off.
Then I used another formula than you did, to read the data from the impedance chart and put it to the equation. And the calculated Qes did not match presented data by RCF obviously, because Bl basically must hold.
You better argue, as this "needs" to be solved. It is good to get to the bottom of the things, and it doesn't matter much who is right. It's okay to be wrong. But given the research, it seems I am not wrong at the moment.
Then I used another formula than you did, to read the data from the impedance chart and put it to the equation. And the calculated Qes did not match presented data by RCF obviously, because Bl basically must hold.
You better argue, as this "needs" to be solved. It is good to get to the bottom of the things, and it doesn't matter much who is right. It's okay to be wrong. But given the research, it seems I am not wrong at the moment.
Yes, I have far far less experience on this stuff than you so trying to learn. I know that pro drivers I have for home hifi use case measure different TS parameters than datasheet values so I'm interested if there is some typical error that could be somehow taken into account before buying drivers. I suspect on some applications, like in home hifi where the system can be oversized, there is actually not that much problem with bad specs compared to application that utilizes every bit of performance a driver has to offer.
I'm currently helping a friend to make a big hifi system that can do 100ppl (10m x 10m outdoors and indoors) party comfortably and trying to figure out the compromize between practical issues, cost, sound and capacity, the usual. You have given interesting knowledge about overhung motors and cooling on this thread which I think that was cruzial information for my quest, to effectively utilize small number of boxes to max while preventing failures. Helps to evaluate options bit better, so thanks!
ps. I was looking at this one https://www.sbaudience.com/index.php/products/subwoofers/nero-18sw1900d/ tuning it quite low, tried to find a driver that could extend response down to ~20Hz for quiet hifi listening between parties, while opening more ports and switching DSP settings for party mode would enable more SPL. If I understood correctly this is what you think is important for cooling high excursion drivers, tuning quite low so that impedance max somewhere 35Hz or above where most of the action is, to reduce power while simultaneously maintaining high excursion. If it's what you ment this would have been accidentally a good plan, but now I know better and can actually be confident about how to approach the use case/problem of high excursion high power handling drivers. As this kind of drivers work at max performance I suspect enclosure construction, amplifier and electrical power feed all need more attention so perhaps I should try figure out how to use multiple drivers and less power instead for better chance of success. Thinking out loud here 🙂
I'm currently helping a friend to make a big hifi system that can do 100ppl (10m x 10m outdoors and indoors) party comfortably and trying to figure out the compromize between practical issues, cost, sound and capacity, the usual. You have given interesting knowledge about overhung motors and cooling on this thread which I think that was cruzial information for my quest, to effectively utilize small number of boxes to max while preventing failures. Helps to evaluate options bit better, so thanks!
ps. I was looking at this one https://www.sbaudience.com/index.php/products/subwoofers/nero-18sw1900d/ tuning it quite low, tried to find a driver that could extend response down to ~20Hz for quiet hifi listening between parties, while opening more ports and switching DSP settings for party mode would enable more SPL. If I understood correctly this is what you think is important for cooling high excursion drivers, tuning quite low so that impedance max somewhere 35Hz or above where most of the action is, to reduce power while simultaneously maintaining high excursion. If it's what you ment this would have been accidentally a good plan, but now I know better and can actually be confident about how to approach the use case/problem of high excursion high power handling drivers. As this kind of drivers work at max performance I suspect enclosure construction, amplifier and electrical power feed all need more attention so perhaps I should try figure out how to use multiple drivers and less power instead for better chance of success. Thinking out loud here 🙂
I see there's a V3 now. I have V2.
https://www.parts-express.com/Dayto...udio-Component-Test-System-390-807?quantity=1
Tmuikku: In short answer to all, yes.
One just does his homework. Putting some good driver through the simulations, finding out what displacement volume is needed to reach the goal, researching drivers that could deliver that in preferred size and weight, checking if the data is true, if the driver can eat the power, and then trying physically. As experienced here, one has to be cautious about the data presented and double check, especially for hot new stuff claiming its superiority.
You do good with the driver choice. It looks like capable respectable driver. The issue with rig scaling is that you can't divide power between people. If you have 5000W rig and 500 people, it doesn't mean 5 people would be happy with 50W of input power.
You seem to do good. Go on...
One just does his homework. Putting some good driver through the simulations, finding out what displacement volume is needed to reach the goal, researching drivers that could deliver that in preferred size and weight, checking if the data is true, if the driver can eat the power, and then trying physically. As experienced here, one has to be cautious about the data presented and double check, especially for hot new stuff claiming its superiority.
You do good with the driver choice. It looks like capable respectable driver. The issue with rig scaling is that you can't divide power between people. If you have 5000W rig and 500 people, it doesn't mean 5 people would be happy with 50W of input power.
You seem to do good. Go on...
what is the difference ?
V2 vs V3
ohh and i just recalled the software that is the DIY version of SMAART
opensoundmeter
https://opensoundmeter.com/en/
manual here
https://opensoundmeter.com/static/manuals/v1.3.pdf
the couch potato inside of me says "get the DATS"
hypothetical speaking , lets say i get out of my couch potato state and want to do some lab measuring.....mmmm....
look at the costs of some 4 wire ohm measuring meters.... Ayyyyyyyyyyyyyyyy !!!
DATS all the way
hypothetical speaking , lets say i get out of my couch potato state and want to do some lab measuring.....mmmm....
look at the costs of some 4 wire ohm measuring meters.... Ayyyyyyyyyyyyyyyy !!!
DATS all the way
Impedance and TS parmeters are quite easy to DIY assuming you already have two channel measurement setup. See ARTA LIMP manual here https://artalabs.hr/support.htm
Few resistors needed, perhapa an enclosure and some wiring. Can be havked together quite fast depending on how permanent you want the setup to be. Might cost 0e if you happen to have some kind of electronic component locker with odd bits and bobs.
If not, the DATS seems fine choise, no unnecessary extra hustle.
Few resistors needed, perhapa an enclosure and some wiring. Can be havked together quite fast depending on how permanent you want the setup to be. Might cost 0e if you happen to have some kind of electronic component locker with odd bits and bobs.
If not, the DATS seems fine choise, no unnecessary extra hustle.
Afraid of originality, seller, transport etc. Already got two, and will probably buy another pair locally. But help is much appreciated.
I am building power dense "efficient" bins.
It is just for me and some gig here and there. Definitely an overkill.
I am developing what I call "port assisted closed box". The port is tuned very low, 25-28Hz, and subsonic/highpass cutoff is set above port tuning frequency. That way the speaker is able to operate in small enclosure efficiently around its impedance peak, not using the impedance valley. It is only possible with high excursion drivers for good results though.
I am building power dense "efficient" bins.
It is just for me and some gig here and there. Definitely an overkill.
I am developing what I call "port assisted closed box". The port is tuned very low, 25-28Hz, and subsonic/highpass cutoff is set above port tuning frequency. That way the speaker is able to operate in small enclosure efficiently around its impedance peak, not using the impedance valley. It is only possible with high excursion drivers for good results though.
Purchased LF18X451s instead. The same coil as on LF21X451 which is marked 2000W/4000W swayed me, as well as price and old school copper/ferrite solution. Displacement capabilities would be limiting for the port assisted design, but this thing still goes to 15mm one way with very little power, and so with double the amount of drivers, it´ll be more than fine. Still, sad that the new neos didn´t end up mine.
The hypervented cooling gets on the nasty side, but in the box, it is still well within the limits of usage needs.
The new neo drivers now have ETA ~12th Oct on TLHP France.
The hypervented cooling gets on the nasty side, but in the box, it is still well within the limits of usage needs.
The new neo drivers now have ETA ~12th Oct on TLHP France.
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So, LN19S400 available at TLHP France, but T&S parameters seem to be off. The awaited/anticipated LN19S450 not available yet, but T&S parameters (Bl) also seem to be off. I cannot resist to test it though, so I am waiting for my local (fairly big)shop to stock them too, and borrow/purchase one for measurement. If these are any good, the X451s will go...
The LN16S400 actually looks as exciting, because with its size, weight and excursion capabilities, it can replace many older 18"s in extremely small and light package.
The waiting though is unbearable.
The LN16S400 actually looks as exciting, because with its size, weight and excursion capabilities, it can replace many older 18"s in extremely small and light package.
The waiting though is unbearable.
Speakers do not have needs really. In modern PA, it is all question of balancing efficiency, size and usability. Once the motor is strong enough, it is happy to work in smaller enclosures. And this one certainly is. It will work well in 2.5-3 cu.ft