Need help replacing drivers in Dual 18" Folded Horn Sub

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hey all

Need some advice as needing to change drivers after i blew them at a party over the weekend in a dual 18" folded horn sub (could hear the bass about 1000M away in all directions), Similar to a W bin but backwards, drivers either end throwing sound out the middle, the box isn't ported fully sealed housing, drivers facing backwards.

The original drivers i had in them were the Cerwin Vega 189es blew them by over powering them (throw the voice coil out of the magnet) i think 2400W was a bit too much.

the T/s for that driver which someone calculated on computer software is=

Z=0
Fs=37
Pe=400
SPL=0
Re=4.65
Le=0
BL=0
Xmax=0
Cms=0
Qms=1.25
Qes=0.37
Qts=0.28
Rms=0
Mms=0
Sd=0
Vas=165
Dia=0.457200914401829
DualVC=0
Type=0

to my knowledge the driver is 400Wrms 3inch voice coil

The driver i am looking at putting in the housing is a Technical pro 18 ZXP18
T/S=
Voice Coil Diameter
5 "VC
Magnet Weight
2x120oz
Resonant Frequency (fs) Hz
25 Hz
Usable Frequency Range
25Hz-2KHz
Sensitivity
97 dB
Nominal Impedance (Re) ohms
8 ohm
DC Resistance
8.9
Coil Inductance (Le) mH
2.3
Mechanical Q (Qms)
8.32
Electrical Factor(Qes)
0.3
Total Q (Qts)
0.29
Comp. Equivalent Vol. (Vas)
545.7liters/18.6 cu.ft
Voice Coil Overhang (Xmax) mm
5.3
Surface Area of Cone (Sd) cm2
1143.5

and its a 4000W peak power driver.

the other option i have is its smaller counter part Technical Pro Z18.1
T/S =
Voice Coil Diameter
4 "VC
Magnet Weight
120oz
Resonant Frequency (fs) Hz
45 Hz
Usable Frequency Range
52Hz-2KHz
Sensitivity
102 dB
Nominal Impedance (Re) ohms
8 ohm
DC Resistance
5.1
Coil Inductance (Le) mH
1.67
Mechanical Q (Qms)
8.18
Electrical Factor(Qes)
0.31
Total Q (Qts)
0.3
Comp. Equivalent Vol. (Vas)
550.7liters/19 cu.ft
Voice Coil Overhang (Xmax) mm
4.5
Surface Area of Cone (Sd) cm2
1182

and is 2500W Peak power.

now i don't know how much the housing is inside, but i did take some measurements which is
440mm angled to 330 then to 350 onto 100 then 750mm back to starting point.
the width inside all this is 610mm.

Now the closet sub design ive found these days is the Bob Audio CS218 Dual 18" double folded horn subwoofer 1600W RMS

BOB AUDIO PASSIONATA

now im already going through and fixing up the housing to make the newer drivers fit in (Lid work mainly) and adding speakons but that will not effect any space inside the driver housing.

Now if your wondering what im running for mid highs, it is Martin Audio Phillishaves and AT and JBL 2" horns
each phillishave is a dual 12"horn loaded i also run 2x 15" folded horn subs aswell with the setup. all run off Crown XLS drivercore amps.

XLS2000 4.9kg for horns (8 ohm loads per channel 375W)
XLS2500 4.9kg for mids (4 ohm loads per channel 775W)
2x XLS 2500 4.9kg in bridge mode for subs (2x drivers per amp 4ohm loads 2400Wper amp)

and iam planing on making another 4 of these Dual 18" subs (own 2 already) as i now have 8 Martin audio Phillishaves 4x JBL 2" horns and 2x AT 2" horns
i will be running
3x Dual 18" folded horn subs
4x Phillishaves
2x JBL 2"
1x AT 2"
Per Side.(6x 18") (8x 12") (3x 2")

Kind regards And many thanks for anyone able to help me out here

PS also open to some other ideas for drivers and amplifiers
(but i like light and powerful amp)
PSS i also have some pictures of the housing internally and externally and the old drivers if anyone would like to have a look. also of my Speaker stack.
 
Well out of all the drivers I'm capable of getting. Mind you I already have 1 z18.1 and it goes harder and more efficient then any other driver I have had that includes. Etone b&c paudio. Jbl is a bit pricey and the closet jbl ive heard to it is the srx and there expensive as hell.
Just remember I'm in Australia too so it's not easy or cheap to get drivers out of the states to is even pushing it to get over here.
 
Hey all

(throw the voice coil out of the magnet)
like 18 hurst suggested,its not so much the power but more an excursion "problem".
you realy need an apropriate high pass filter,to make sure excursion stays in limit.
it looks like its a bandpass horn,
to find the right driver you realy need to model the horn with the driver.
if you had a drawing or something ,whe could sim it for you.
regards erik
 
Well I think it was just too much power but if I compared that sub with a front loaded dual 18 I bet id get more sound out of them then I do with the cerwin Vegas that's my problem I can see is that the drivers are quite bit.old fashioned to keep up with bass demands theses days. I'll post a drawing in the next 24 hrs of the horn shape for you. Also the sub was crossed at 125hz with a 24db litz crossover point

If the cerwin Vega had a 4 inch voice coil I wouldn't have had this problem.
 
I'd recone the Cerwin Vegas

To protect them, use the proper high pass filter and adjust the limiter to prevent overpowering the subs.

https://reconingspeakers.com/products-page/brands/cerwin-vega-189es-aftermarket-recone-kit/

Once the proper filtering and limiting is set for the subwoofers, you won't blow them up and they will sound much better.

I'd like to recone them but the magnets are ****** too. One voice coil wedge it self in the magnet had to rip it out. And they both have all dirt ands metal p shavings in them. one of the voice coils ripped in half. I never just blow a speaker or burn a coil out. I always do a good job a blowing something up
 
Also the sub was crossed at 125hz with a 24db litz crossover point

If the cerwin Vega had a 4 inch voice coil I wouldn't have had this problem.
the above is a low pass filter
i'm talking about a high pass filter(low cut) to prevent overexcursion.
usualy in the range from 25 to 50 hz.
here is an old example excursion plots with and without hpf
filterdjk.jpg
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.