18Sound 18LW1400 vs JBL 2242H

[2100]

Hello guys,

I'd like some comments from anyone who has done any remote comparison/listening between the 18LW1400 and the 2242H drivers in a bass reflex box. The 18sound is used in the EAW SB1000 and KF850, serious hardware. The JBL 2242H is also sort of legendary, and it shows in the price (2X that of the 18Sound).
It would probably be easier to sell the 2242H here locally, but this is a small issue.

I'm interested in doing up a sub (with EQ) and want to do down to 30Hz as it won't be for home theatre. Approx 160L internal vol excld driver/port displacement. Not really going for outright SPLs, 100dB nominally and 110dB for peaks @ 1m would be absolutely fine. My room is small (5m by 3.5m), so its gonna rock.

Will be powering it with a Yamaha P7000S (700W into 8ohms, 20-20kHz bandwidth, 1900W into 8 bridged).

Thanks and Merry Xmax, oppss....Xmas!

[cowanaudio]

G'day 2100

I've used the 18LW1400 in the home, as well as several JBL's, (2206, 2226, 2241, 2245) but not the 2242. I've also used the 18Sound 18LW1400 and the 15LW1401.

The 18LW1400 is an excellent driver by all accounts and the best value out of this bunch. It is cleaner at high excursions than the 2241 and likely slightly better than the 2242.

For the levels you are after you would be better off looking at a driver like the 15NLW9500, this will give you all the output you require, with very low distortion and thermal compression. The 18" driver will deliver much more than you need. I ran my pair in 250L@22Hz with 1100W RMS each.

Cheers

William Cowan

[cowanaudio]

G'day again

Don't underestimate the size of port required when trying to minimise compression when using these drivers. Many people ruin a great sub with a port that is just too small. Here's an internal picture of one of my 18LW1400 subs.

[cowanaudio]

And the outside, without the grill.

[kesa32]

Hi William, are the 18sounds easily obtainable here in oz?
l have a mate who wants to build somthing next year, how would your horn loaded subs intergrate with ported mtm design speakers?

cheers ken

[2100]

Hi there William,

You are so very right about vent port sizing. I ran the numbers in WinISD Pro and if i tune it to SBB4 (ie 31Hz for the 18LW1400), geez its absolutely unbelivable! I use the Flare it program as a rough guide. Though core limit compression is quite high and presents no problem, the problem is chuffing limit of about 17m/s for, and it only does about 108dB for 25Hz before exceeding that speed, even for say a 160L box, 50cm port length and 20cm dia vent.

In fact 17m/s is assumed with some "masking", I guess with some music like low drums I'd hazard a guess you stilll can hear very slight chuffing from 2-3m away. Best is to do 10m/s.

So flaring is definitely needed, i am not sure if my local carpenter knows how to flare a rectangular port slightly. The port is now tuned to 34Hz 160L box so that i can utilise more of the 35Hz region for high SPL, as the vent speed is the limiting factor for 25Hz region.

Apologies for the rant William, I guess you know this like the back of your hand! I'm just putting it down here for the benefit of anybody who's trekking the same path in the future, as its not documented here or speakerplans.

In WinISD Pro, all the curves looks pretty similar bt the 18LW1400 and 2242H. Power compression specs are very similar too. Both have reinforced pleated cones, the 2242H uses fibreglass and the 18Sound i believe is just paper but treated both sides (weather proof), which probably improves the self damping properties and plup strength also.

Thanks a lot for sharing bro, I shall go for the 18LW1400. The fact that you recommended the 18Sound as its better at high excursions than the 2241 (7.6mm Xmax) means lots. Easily can hang around the 2242. The 2242 H2 and H3 curves are amazing.
I figured i'd go for 18" instead of 15", just do it right once and for all. Besides the Fs for the 15LW1401 is 42Hz, that's a bit high and I don't want to push it. I actually wanted to go for the 21LW1400 or new B&C 21SW150 but it is just too big!

Merry Xmax!

[2100]

William, one last question.

How would you find the "musicality" of both the 2241 and 18LW1400, from 25-100Hz?

I'm looking for the tone of the bass, as in enjoyability of the music.

[cowanaudio]

G'day 2100

They are both very clean drivers, and properly implemented will blend seamlessly with your top end. Many years back I had a room at the Melbourne HiFi Show and was voted having the best bass of the show, using a JBL 2226 based sub (300L@16Hz with passive eq).

Ken

Contact me when you're ready to go.

Cheers

William Cowan

[freddi]

hi William - how would you build this type?
http://img.photobucket.com/albums/v3.../ADSCF2511.jpg

[cowanaudio]

Freddi, I see no technical advantage using a Karlson type enclosure. They are a relic of a time gone by that was devoid of any accurate computer based modeling. If you want high efficiency, start studying horns or direct radiating driver arrays. It is relatively easy now to achieve an excellent result on the first cut of a loudspeaker enclosure, assuming your models reflect what you build. The last few tapped horns I built measured within +/-1dB of the predicted response. Accurate computer models are your friend.

Cheers

William Cowan