Help - Low frequency horn – T18

As you guys suggested here are more comparison regarding the sections

S1=S2 for B and C simulation

An externally hosted image should be here but it was not working when we last tested it.


Click here for larger image: https://s15.postimg.org/obvt1ljh7/Hornresp_sections.png

An externally hosted image should be here but it was not working when we last tested it.


Click here for larger image: https://s22.postimg.org/7bhbkl2ht/Hornresp_sections_input.png

An externally hosted image should be here but it was not working when we last tested it.


Click here for larger image: https://s21.postimg.org/wvwvpebgn/Hornresp_sections_results.png
 
Hello Marcelo, could make me an understanding?
Because I love the sound of t18, I will make 4 offices, and I am in the choice of speakers, to as close as possible to 50hz.
Following the measures granted in post # 3, and taking its title as the same intention, the speakers that best answered in t18 were. In this order...
HPX 2180
Sub1000
Esx185
I could confirm this to me?
Or a new tip?
Thank you.
 
Hello DJGARAM,

I selling my two T18. Let me know if you have interest.


The following order are right, some guys helped me to to improve the simulation. Would be better to find more simulations and compare all of them before make a conclusion. Once I just leanerd the advanced method to unfold cabs it should be used to improve this simulation.
 
If loaded properly a T18 can be a wonderful cabinet. We have 12 running and they get a lot of attention from other users because of the output and sound. Load them with the sub standard drivers and you get a bad cab.

We have a lot of clients requesting them for their gigs. That's anything from extreme EDM through rock / metal to jazz gigs. They can do it all. But, that's because we have them loaded up with the correct drivers. Please do not skimp on the 18"s. I can highly recommend the RCF LF18G401.

Also. When building the T18, brace properly. Add bracing on that bottom panel. They like walking around with high power drivers in.

AND: Use real amps. Buy decent second hand touring quality amps.
We power ours with simple old 5000VZ's. They make all the difference. We find it to sound better than our LAB FP10000Q's.

T18's have wonderful throw when used in stacks. We can throw all the way to the back of sports fields. Much further than the line mid highs we use above them.

So. Its actually very simple. Load them with real drivers. Units with strong BL's above 22 preferably, QTs in the region of 26 and with proper excursion. The horn unloads quickly close to the 40Hz high pass. Also make sure to look out for dual suspensions. Get a driver with two spiders. Keep that VC centered.

And. Stop looking at the spec sheets and predicted response curves. It all changes when you run it through the crossover. You have to high pass a T18 at 40Hz. Also, EV's old datasheets specified anechoic environments. That means no reflective surfaces. Real world measurements are better than their plots.

Simulated response of a single T18 loaded with a RCF LF18G401 with 900w into the driver:
1x-t18-rcf-900w_1_orig.png


Simulated response of six T18's loaded with RCF LF18G401's with 900W each driver:
6x-t18-rcf-900w_1_orig.png
 
Hello Hugo
I found 2 x SB1810 in the basement of the city hall they where about to get thrown out. They are massive speakers the drivers are unfortunately shot roaches made a meal of the cones and the compression drivers are gone. Which of RCF 10" would be good for the mid?
 
50 hz

I need a scaled down T18. A, T12 or T15 tuned for bass guitar, that is 50 or 60 hz. I'm not technical but I know what sounds good. Bass cabs have a wider freq. response than a sub but the T18 is much to large for gigging bass players. The Cubo boxes look a lot like a scaled down T18 but don't have same the same throat as a T18 so they are not going to project mid range like a T18. Help.
 
A 50hz horn will be very large. Maybe look at the old school horns that have a vented back chamber to get a smaller horn with a bit of bass. I don't think many 50hz horns will get up to 3.5k without assistance.

Cheers,
Rob.

Edit: something like these out of the Fane loudspeaker book.
 

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at first thought you meant a Fitzmaurice "T18" dunno if Karlson have what you want but do have virtue. Acoustic Control's 115BK scaled 1.2X for an 18" would be 32"T x23"W x 16" external with tuning in the low 40s.

18" which extend high might be hard to find - EV's old 18B went high on axis

1qXwfSW.jpg


little box fudge sim - vent should probably be shortened at least 15%

o2VfNQS.jpg
 
What would the throat area be like in a cabinet tuned for 50hz on up to say 3500hz?
Cubo's and the T18 as far as I can tell, are band pass boxes. That means that they limit the upper frequency response up to 2 or 3 octaves at best, after which you'll find a series of dips or peaks. Typically they're used by bass guitarists, I suppose in combination with a regular guitar cabinet / speaker for the higher tones.
 
What would the throat area be like in a cabinet tuned for 50hz on up to say 3500hz?

Academic since it requires a driver with an effective Qts' = 2*50/3500 = 0.0286. 🙁

Based on St = Sd to closest frame size: [50*3500]^0.5 = ~418.33 Hz = ~13543/pi/~418.33 Hz = ~10.31" eff. dia./~83.4"^2 = 12" frame.

From above, the lower Qts' is the more horn loaded BW, so find the driver to 'find'/design the horn or at least an acceptable trade-off such as Rob's vintage suggestion with a 12" mounting adapter and DSP to 'taste'. 😉

GM