I looked into the Eighteen Sound mids. None of their models have a significant SPL advantage over the SB except for the 6NMB420. But this one doesn't have great dispersion.
New idea. Instead of four 6" SBs. I will use five FaitalPRO 5PR120. Can't find measurments of it but judging off the performance of the other FaitalPRO mids and the fact they kind of market this as their highest performance, lowest distortion midrange I'm guessing it's very good. Five of these together actually offer about 4-4,5 dB more SPL. And their F3 in a 15 L total sealed box is actually right around 300 Hz. Seems like a great match to me.
Yes, that's very reasonable. But keep calculating the weight, wouldn't be the first project which performs great but fails in the end anyway because it's almost impossible to handle or is too much in rigging effort needed.
The LT6 is not an option for a horn top IMO because it's a a magnetostat and not an AMT and the poor power handling (40W per unit) compared to the AMTs. Magnetostats become suddenly shouty over a certain level. Nevertheless, I didn't know the LT6 and they seem excellent for the price, I'll keep them in mind for other projects. Thanks for the find!
Yes, the BEYMA TPL-150 has to be modified at the back chamber to get rid of the 3k (?) issue but that's not rocket science. I don't see an issue of having headroom. Tweeters are much easier to kill (ie feedback), take it as a plus of 6dB headroom at any time! 😀
On the SBA NERO-6MRN150D I don't like the resonances at 2,1 and 4k but well, others got resonances too. The B&C 6NSM51 got the great advantage of very effective cooling because of the sealed alu back chamber. The SBA got foam surrounds, I'm not that fond of these but well, you always got to eat the one or other compromise.
Again, having headroom never hurts, cone mid and bass drivers take an overload much better than tweeters. Just keep in mind where the limits are. Let's get the concept first and gather driver candidates then decide what fits best.
For 8-12" drivers: you can also consider a V-shaped configuration to save space. I haven't done that myself yet though, others surely have more expertise than me.
The Radian will have much less headroom. There's no harm in having more capable tweeters. 😉 But it's your decision and if you are convinced these are the better option for you, then go for it, it's your speaker, your taste and your money! 😀
Hi, great to hear to problem with the Beyma is easily fixable! In that case I think we've found ourselves the perfect tweeter. You're very right about the headroom, can never have too much. Let's stick to the Beyma actually. I think the Beyma with the FaitalPRO 5PR120s is a rocking combo! Especially with five mids and four tweeters those mids are only 2 or 3 dB behind. I'm comparing 12" mid woofers now to find which one offers the best balance between SPL and F3. 10s aren't gonna suffice. But I think it should be possible to get 12s to play nicely to 330 Hz?
The B&C 6NSM51 looks like a great contender too and the aluminum back chamber is indeed a great advantage in cooling and in the fact it doesn't need an external enclosure. The thing is though looking at the 8" version I'm sure it has very low distortion and great dispersion. The only thing I question is the decay and the F3. The waterfall plot of the 8" doens't look great.
In the specs it says "net air volume taken by driver" is 2 L. Which means that with wall thickness and the driver assembly inside the internal volume is just 1,5 L max. If I put this in a model it gives a F3 of 337 Hz. Isn't that a bit high.
Other than those two concerns it seems like a top notch mid to me. The 5PR120 however has a aluminum dustcap to help with cooling which is also something to consider.
The B&C 6NSM51 looks like a great contender too and the aluminum back chamber is indeed a great advantage in cooling and in the fact it doesn't need an external enclosure. The thing is though looking at the 8" version I'm sure it has very low distortion and great dispersion. The only thing I question is the decay and the F3. The waterfall plot of the 8" doens't look great.
In the specs it says "net air volume taken by driver" is 2 L. Which means that with wall thickness and the driver assembly inside the internal volume is just 1,5 L max. If I put this in a model it gives a F3 of 337 Hz. Isn't that a bit high.
Other than those two concerns it seems like a top notch mid to me. The 5PR120 however has a aluminum dustcap to help with cooling which is also something to consider.
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Actually, appart from just the modeled F3. Also on the FR graph it rises a ~14 dB between 300 Hz. If this has to be EQed flat a lot of it's efficiency would go to waste. I think the 5PR120 is the most suitable option.
Well, a 5-6" driver is a midrange in PA use. You will never find a that high spl which goes lower without a boost. The same goes for 8", they go a tad bit lower than the 6" but have to be boosted lower or don't have the spl. Both B&C (6+8") got 250/500W so they take a ton of power. But you are right, it's useless to boost 14dB. However, if you want to xo lower then you need something different anyway. At what frequencies do you want to cross each way? That determines what driver is needed.
I think the Beyma AMT is a good choice, I'm glad we've found at least the first driver! 😀
I think the Beyma AMT is a good choice, I'm glad we've found at least the first driver! 😀
I've modeled all the best 12" options, wrote down their F3 in 40 L sealed box and max SPL. The two winners are both 18 Sound units. It's just a matter of picking one or the other. The 12NW350 has a max SPL of 127 dB with F3 @ 117 Hz. The other contender is the 12NLW9300 with a max SPL of 126 dB with F3 @ 86 Hz. The F3 of the last driver mentioned was especially low actually. Much lower than any other I compared. Especially with triple roll surround. There are some other options that might go this low but most of them have rubber surround and nowhere near the SPL capabilities.
I think the 12NLW9300 is probably the best pick since we don't want to cross to the subs too high. And sure I could DSP the 12NW350 to meet the subs lower. But that would mean it's 1 dB higher output will go to waste and it might actually end up being slightly less loud than the 12NLW9300.
I think the 12NLW9300 is probably the best pick since we don't want to cross to the subs too high. And sure I could DSP the 12NW350 to meet the subs lower. But that would mean it's 1 dB higher output will go to waste and it might actually end up being slightly less loud than the 12NLW9300.
I like the 12NLW9300 and I agree, it seems to be the best choice so far. I'm just a bit puzzled because my sim shows a higher f3 and still much less enclosure volume, about 10l for 120ish Hz for one driver. How many drivers did you simulate in 40l? 3? Maybe I've got a different parameter set than you do. For simplicity just let's simulate with just one driver with its 'own' share of volume.
The 12NLW9300 is a driver that needs very little volume and a vent tuned to 60-80 Hz is possible and helps cooling too besides reducing the excursion. The vents start to get problematic because above ~100 Hz the human ear becomes increasingly sensitive to phase differences. Below that it doesn't matter, otherwise BR, BP, TML etc would be unbearable. 😀
The 12NLW9300 is a driver that needs very little volume and a vent tuned to 60-80 Hz is possible and helps cooling too besides reducing the excursion. The vents start to get problematic because above ~100 Hz the human ear becomes increasingly sensitive to phase differences. Below that it doesn't matter, otherwise BR, BP, TML etc would be unbearable. 😀
Great! No modeled two drivers in 40 L. I could still reduce the volume slightly for F3 around 90 Hz. More than 2 of either 10 or 12" drivers won't fit in a four tweeter (~64 cm) high cabinet. A "V" configuration would be awesome if possible. It would reduce rabinets vibration and the ability to use quad drivers would make it a lot easier to reach the desired SPL with a more driver options.
Just for clarification: Which dimensions where you aiming for? And are these somewhat flexible or set in stone?
25 L for two 12NLW9300s gives a 90 Hz F3. Which is quite small. Should probably anyway keep it a bit bigger to allow for some more excursion. If cooling is really that big of a deal i might even look into something like a in-wall heatsink.
I somehow missed a part of that one, sorry. The crossover frequencies of 25Hz - 125Hz are somewhat misleading. The 25Hz are not the bottom reproduced frequency but the low-cut (subsonic) filter that should be used to protect the drivers. The 40Hz will be reached with a single sub and is actually lowered in a stack, a 4+ stack cluster should be able to reach ~35 Hz, An 8+ stack indoors will probably even reach 30Hz.
The thing is that I obviously don't want to make the top cabinets TOO big. So I'm thinking to put in each four Beymas and 5 FaitalPROs because that combo matcha almost exactly in total height and seems like a good total height per cabinet (4 x 16 = 64 cm). The second thing is that I don't want to make the enclosure pretty much anny taller than the driver arrays because I want to be futureproof and want to be able to stack two cabinets per side once I've made enough to invest in a second pair. So yes you could say that ~64 cm height is pretty much set.
Hoffman's Iron Law: Efficient, Low, Small, pick two.
It is possible to "beat" any cabinet design in at least one aspect.
Hornresp is a great modeling program.
Akabak allows even more advanced modeling, but much more difficult.
Bjorn Kolbrek is a great source to get you into horn knowledge :
https://kolbrek.hornspeakersystems.info/index.php/publications
Horn Theory: An Introduction, part 1 (Bjørn Kolbrek, AudioXpress, March 2008)
Horn Theory: An Introduction, part 2 (Bjørn Kolbrek, AudioXpress, April 2008)
"Better" depends on what you are attempting to accomplish.
At ~1550 Hz, both 6" or 8" -6dB horizontal dispersion is more than 90 degrees.
Direct radiator line array vertical dispersion (and cancellation patterns) are determined by center to center spacing and line length.
Given the same excursion, 8" will have more Sd (cone area) for a given line length, so will have more displacement, output and efficiency.
Speaker Dave (David Smith died January 18, 2024) papers may help you understand line array behavior:
https://www.diyaudio.com/community/...ducers-line-arrays.165596/page-3#post-2257395
https://www.diyaudio.com/community/...heir-behavior-through-simple-modeling.388279/
And in this thread Speaker Dave presents a simple line array model:
https://www.diyaudio.com/community/...heir-behavior-through-simple-modeling.388279/
And another :
https://www.diyaudio.com/community/...h-simple-modeling.388279/page-10#post-7126076
Anyway, nothing really "simple" about line array behavior 😉
Discussing response with no actual raw measurements to compare is not very useful.
A horn array's increased mouth area increases LF efficiency, but it's Fc (cutoff frequency) is still determined by the horn path length, which is unchanged in multiples.
I don't think you will find an actual measurement with the low corner dropping more than a few Hz below the horn Fc when used in multiples.
Art
Anybody have any knowledge about if a "V" configuration where the drivers are almost opposed and the throat is the top of the "V" would work for the mid bass?
https://audiojudgement.com/folded-horn-speaker-design/
According to this article "scoop" horn offer great low extensions while also using the driver's direct radiation. Seems like a great option for the subwoofer cabinets. Perhaps also with two opposed drivers in the middle with a exit out the front for the direct radiation and the horn exits on the outsides of the cabinet.
https://audiojudgement.com/folded-horn-speaker-design/
According to this article "scoop" horn offer great low extensions while also using the driver's direct radiation. Seems like a great option for the subwoofer cabinets. Perhaps also with two opposed drivers in the middle with a exit out the front for the direct radiation and the horn exits on the outsides of the cabinet.
The 1550 Hz I was talking about wasn't necessarily my desired crossover. It was the about the wavelength of an 8" driver being around that frequency so I was wondering if it 8" mids would start suffering from comb filtering from that frequency.
I haven't really set a XO frequency yet. But the Beyma can go pretty low and doesn't show a rise of distortion to the bottom yet in the AudioXpress measurments which go to 2 kHz. So maybe a crossover around that 1500 Hz would be possible.
So you're saying 8" mids would perform fine without significant dispersion issues at 1500 Hz? Appart from it's decay the 8NSM64 would be a solid driver with much more SPL on tap. You recon the decay issue could be helped by imporved damping inside it's enclosure?
I found out however that according to AudioXpress the sensitivity is actually 89 dB rather than the specified 100 dB.
The mid bass/midrange crossover frequency kind of depends on what the mid bass is will be capable of.
Did some searching again. I literally can't find even a 8" mid that should outperform the 5PR120 in SPL. They might go lower. But the 100 dB sensitivity at 100 W RMS seems unbeatable.
DHL says Monday for my pair 5PR120.
I'll compare it to the PHL1660NdM-SQ2 I've been testing.
I'll compare it to the PHL1660NdM-SQ2 I've been testing.
I said at ~1550 Hz, both 6" or 8" -6dB horizontal dispersion is more than 90 degrees.
That may or may not be an issue, you don't seem to have decided on what dispersion pattern you want.
Direct radiator line array vertical dispersion (and cancellation patterns) are very erratic, which is an issue.
I don't know what "decay issue" you are writing about.