bonjour de France, j'ai un peu de mal a suivre la conversation avec mon anglais lol
J'ai actuellement 2 boîtes fermées avec 2 lab12 dans chaque boîte. (j'ai un traitement acoustique fait par un pro je suis en dessous de 300ms rt60 sur tout le spectre sauf en dessous de 50hz)
Je voudrais savoir si le lab12 en montage roof, perd-on en qualité des basses ? en intérieur je trouve le 60-120hz super mais être en 60hz c'est brouillon et il n'a plus aucune sensation physique (manque de spl peut être)
et pour choisir si j'ai bien compris le meilleur en qualité sonore serait "corne avant"
alors comme je n'ai qu'une pièce de 40m2 et qu'est ce qu'on peut considérer comme une très basse d'accord 20-10-5hz ? car en théorie je n'utiliserai pas toute la puissance.
MERCI
J'ai actuellement 2 boîtes fermées avec 2 lab12 dans chaque boîte. (j'ai un traitement acoustique fait par un pro je suis en dessous de 300ms rt60 sur tout le spectre sauf en dessous de 50hz)
Je voudrais savoir si le lab12 en montage roof, perd-on en qualité des basses ? en intérieur je trouve le 60-120hz super mais être en 60hz c'est brouillon et il n'a plus aucune sensation physique (manque de spl peut être)
et pour choisir si j'ai bien compris le meilleur en qualité sonore serait "corne avant"
alors comme je n'ai qu'une pièce de 40m2 et qu'est ce qu'on peut considérer comme une très basse d'accord 20-10-5hz ? car en théorie je n'utiliserai pas toute la puissance.
MERCI
"cop" Desole, but this is an ENGLISH language forum. You must post en ANGLAIS. It's in the rules. You must do the translation work, don't make us do it.
oops sorry I forgot to translate: hello from France, I have a little trouble following the conversation with my English lol
I currently have 2 closed boxes with 2 lab12 in each box. (I have an acoustic treatment done by a pro I am below 300ms on the whole spectrum except below 50hz)
I would like to know if the lab12 in roof assembly, do we lose in quality of the bass? indoors I find the 60-120hz great but be 60hz it's messy and he no longer has any physical feeling (lack of spl can be)
and to choose if I understood correctly the best in sound quality would be "front horn"
then as I only have a room of 40m2 and what we can consider a very low agreement 20-10-5hz? as in theory I will not use all the power.
THANKS
I currently have 2 closed boxes with 2 lab12 in each box. (I have an acoustic treatment done by a pro I am below 300ms on the whole spectrum except below 50hz)
I would like to know if the lab12 in roof assembly, do we lose in quality of the bass? indoors I find the 60-120hz great but be 60hz it's messy and he no longer has any physical feeling (lack of spl can be)
and to choose if I understood correctly the best in sound quality would be "front horn"
then as I only have a room of 40m2 and what we can consider a very low agreement 20-10-5hz? as in theory I will not use all the power.
THANKS
Don't know what you mean by "roof assembly", but for the most accurate reproduction (the best in sound quality), the order is generally closed box, front horn, tapped horn.
The horns give more SPL for a given amount of power, so will give more physical feeling. A TH can be made smaller than a FLH for the same low frequency output. The "messy 60Hz" may be a room problem different cabinet designs won't help.
Your closed box cabinets would be a better choice for very low frequency reproduction (below 20Hz) than a 36Hz Fb TH like the one this thread is about, which is more than -24dB down at 20 Hz from 40 Hz.
The horns give more SPL for a given amount of power, so will give more physical feeling. A TH can be made smaller than a FLH for the same low frequency output. The "messy 60Hz" may be a room problem different cabinet designs won't help.
Your closed box cabinets would be a better choice for very low frequency reproduction (below 20Hz) than a 36Hz Fb TH like the one this thread is about, which is more than -24dB down at 20 Hz from 40 Hz.
bad translation, I meant to charge in "horn"
that's why I was wondering if with a particular design or a larger case it would be possible to charge it as a "horn" and that it goes down flat up to 5hz let's admit?
is it the lab12 that makes it impossible or just that it is in charge of the horn?
also i saw that "acoustic impedance" was important for the physical feeling and to increase it there are only 2 ways
either increase the total surface of the membranes "Sd" therefore multiply the sub or increase in diameter.
or horn loading which naturally increases acoustic impedance.
what do you think?
and for the feeling at 60hz in music I agree but in films the effects of "lfe" go lower, for example I like the starting scene of the batmobile from the last Batman (followed by a chase in the rain)
the start is done at around 30hz at -5dbfs on the disc information.
with a friend who has 4 um18 indoors in 20m2 I have a huge physical feeling, while remaining "clean" "coherent "
that's why I was wondering if with a particular design or a larger case it would be possible to charge it as a "horn" and that it goes down flat up to 5hz let's admit?
is it the lab12 that makes it impossible or just that it is in charge of the horn?
also i saw that "acoustic impedance" was important for the physical feeling and to increase it there are only 2 ways
either increase the total surface of the membranes "Sd" therefore multiply the sub or increase in diameter.
or horn loading which naturally increases acoustic impedance.
what do you think?
and for the feeling at 60hz in music I agree but in films the effects of "lfe" go lower, for example I like the starting scene of the batmobile from the last Batman (followed by a chase in the rain)
the start is done at around 30hz at -5dbfs on the disc information.
with a friend who has 4 um18 indoors in 20m2 I have a huge physical feeling, while remaining "clean" "coherent "
In the Hornresp simulations in post #6, you can see the excursion minima (Fb) of the TH is around 36Hz, and the horn path length around 3 meters long, roughly 1/4 wavelength. Below Fb, the front and rear output become out of phase, the excursion goes up while output drops.
Doubling the path length of the horn would lower the response around an octave. The Danley DTS-10 is an example of a TH with an Fb around 18Hz using drivers similar to the LAB-12, with dimensions of 59.5 x 44 x 16 inches.
A 5 Hz tapped horn is theoretically possible, but would require around 17 meters of horn path, a huge enclosed volume, and would only remain "clean" and "coherent " up to around 20Hz.
Doubling the path length of the horn would lower the response around an octave. The Danley DTS-10 is an example of a TH with an Fb around 18Hz using drivers similar to the LAB-12, with dimensions of 59.5 x 44 x 16 inches.
A 5 Hz tapped horn is theoretically possible, but would require around 17 meters of horn path, a huge enclosed volume, and would only remain "clean" and "coherent " up to around 20Hz.
Sorry for making this tread go even longer but....
The PAL 12 seems lie a perfect little sub for my application, I have it down to this or a single 18" BR
One thing that is giving me cold feet at this point is the fact that the LAB12 is now an OLD driver The price has also gone up incredibly for a technology that has not changed. When Eminence was only Eminence I had some faith that the driver would stay in production. But, with B&C being in control now I have a bad feeling for the future of the driver for some reason.
Is there another driver that is proven suitable in this enclosure that gives similar performance for a similar price? I'm not afraid to throw more power at it if need be.
Chad
The PAL 12 seems lie a perfect little sub for my application, I have it down to this or a single 18" BR
One thing that is giving me cold feet at this point is the fact that the LAB12 is now an OLD driver The price has also gone up incredibly for a technology that has not changed. When Eminence was only Eminence I had some faith that the driver would stay in production. But, with B&C being in control now I have a bad feeling for the future of the driver for some reason.
Is there another driver that is proven suitable in this enclosure that gives similar performance for a similar price? I'm not afraid to throw more power at it if need be.
Chad
The specs for the Dayton Audio MX12-2 suggest that it might work well in a PAL12 box, with a predicted smoother response to. And at about $150, it's cheap enough to try it out. Make sure to confirm first that its physical dimensions allow it to fit in the box though.
Thanks Brian,
They look to be able to fit physically. Now I need to finally get un-lazy and learn the software I guess..
The pricing is indeed attractive which brings them closer to the original $325 price point. I wonder how well the Dayton holds up versus the Lab12. Definately like the idea if the rubber surround on the Dayton but like the Kevlar impregnated cone on the Lab. In other words, I wonder of it can it take the pressures in a professional application.
They look to be able to fit physically. Now I need to finally get un-lazy and learn the software I guess..
The pricing is indeed attractive which brings them closer to the original $325 price point. I wonder how well the Dayton holds up versus the Lab12. Definately like the idea if the rubber surround on the Dayton but like the Kevlar impregnated cone on the Lab. In other words, I wonder of it can it take the pressures in a professional application.
Here's how the two compare in the PAL12 - LAB12 in red, MX12-2 in green. Theoretically you give up a bit of output at 40 Hz and gain more output below that. And the MX12-2 has 6mm more Xmax than the LAB12, so overall you should get more output than with the LAB2 if you feed it more power.
Of the two however, I'd probably build neither, unless I had the drivers on hand and I wanted to build a TH with them.
Of the two however, I'd probably build neither, unless I had the drivers on hand and I wanted to build a TH with them.
First off, thank you for dong this Brian, very much appreciated.
It's a 9CuFt cab if I recall, and a 9CuFt with a modern 18 will also really boogie in my application (under a set of 12/horns)
Do I want a 12" tapped horn for the footprint and because it's different? I sure do.
Am I also swayed by simplistic and proven designs? Yep!
Not opposed to doing a dual 12 sub if I could find the right driver. The Thoman Pyrit 212 is really interesting, But, the specs for the same box vary wildly depending on whose badge is on it.... AND I'm in the US so......
It's a 9CuFt cab if I recall, and a 9CuFt with a modern 18 will also really boogie in my application (under a set of 12/horns)
Do I want a 12" tapped horn for the footprint and because it's different? I sure do.
Am I also swayed by simplistic and proven designs? Yep!
Not opposed to doing a dual 12 sub if I could find the right driver. The Thoman Pyrit 212 is really interesting, But, the specs for the same box vary wildly depending on whose badge is on it.... AND I'm in the US so......
Is there a thread or resource you would recommend to dive into the Offset Transmission Line a bit?
Is there a significant gain over vented at this point? (pro use)
Is there a significant gain over vented at this point? (pro use)
Chad,
B&C does not have a driver in their line up with TS parameters equivalent to the LAB12, I doubt they would stop production on it.
Hmm.. maybe not exactly equivalent, but I suspect that one of these would give the LAB12 quite a challenge... 🙂
https://www.bcspeakers.com/en/products/lf-driver/12-0/4/12fg100-4
https://www.bcspeakers.com/en/products/lf-driver/12-0/4/12fg100-4
http://www.quarter-wave.com/index.html
For prosound you want inverse tapered with the terminus = (Sd), so basically design whatever BR alignment you want with a (Sd) size vent and convert to a tapered line like I did way back when all I had was this math:
T/S max flat alignment:
Vented net volume (Vb) (L) = 20*Vas*Qts'^3.3
(Ft^3 = (Vb)/~28.31685)
Vented box tuning (Fb) (Hz) = 0.42*Fs*Qts'^-0.96
F3 (Hz) = Fs*0.28*Qts'^-1.4
(Qts'): (Qts) + any added series resistance (Rs)
Agreed, but requires a lot more power to use it's potential 🙂
Wasn’t aware of the B&C 12FG100-4, but it’s higher FS of 34Hz compared to 22Hz for the LAB12 is quite a difference. The physical differences are enough that the 12FG100 won’t be a “drop in” replacement for front mounted applications.
The 12FG100-4 bolt circle is the same as the LAB 12, but it’s baffle cutout diameter (and Sd) is slightly larger, so a retrofit in mRgSr’s PA12 would probably require a slightly larger cutout to keep the surround clear of the opening.
The B&C 12FG100-4 (light gray lines) models well in mRgSr’s PA12 design:
Given over twice the power (839 watts at 50 volts at the impedance minima of 2.98 ohms to reach Xvar of 14mm, vs. 365 watts at 40volts into 4.38 ohms to reach Xmax of 13mm), it appears the 12FG100-4 would have greater output potential with a bit more extended and smoother response than the LAB12.
Given the larger voice coil and additional cooling vents, the power compression from voice coil heating would probably be less for the 12FG100-4 at those power levels.
Art
Note that there's also an 8 ohm version of that driver that might be even more comparable to the LAB12