I’m not sure. I found the 2242 idea after had already ordered the 2268's. Then someone blew air up my *** that 2268's have sort of a strange or different sound because of the neo-magnets and might not be the right choice for me. I think the 2242's listed for around $600 each. I got nervous about my choice. That's when I sort of talked myself into the LW1400's. Guessing, I get the idea you like the 2242's and AJ likes the 68's. Kris
To the person that believes in the Easter Bunney and thinks the JBL 2268 has 23mm x-max.
Yes a sealed box would eat up all that x-max. A 2268 in a Qtc=0.707 (maximally flat) box would be 3dB down at 75hz. Compared to the reflex box at 31hz it would hit 23mm x-max with only 5.5KW
Why would JBL build a driver that took almost 7X its maximum power rating to take advantage of its x-max?
IF it did have 23mm x-max, AND could handle 5.5KW, then it could play about 120.5dB at 31hz, assuming NO power compression (we must believe in the tooth fairy too). The vented box under the same impossible 5.5KW input and no compression would be playing 130.1dB, but only moving about 11mm.
As regards the Aura 1808, the radially polarized gap is about 2" long, and the coil is underhung. It does have a real x-max of 3/4" (18mm).
Drivers like the TC Sounds are a different kettle of fish. Being overhung they are less efficient, about 7dB~9dB less than the PA drivers under discussion (not to mention tipping the scale at over 45 pounds). I'm sure they can handle the 3KW they're rated at for car stereo 'burps' and typical home theater use, but if you try that kind of power long-term at a dance party I think you will be in for a surprise.
Yes a sealed box would eat up all that x-max. A 2268 in a Qtc=0.707 (maximally flat) box would be 3dB down at 75hz. Compared to the reflex box at 31hz it would hit 23mm x-max with only 5.5KW
Why would JBL build a driver that took almost 7X its maximum power rating to take advantage of its x-max?
IF it did have 23mm x-max, AND could handle 5.5KW, then it could play about 120.5dB at 31hz, assuming NO power compression (we must believe in the tooth fairy too). The vented box under the same impossible 5.5KW input and no compression would be playing 130.1dB, but only moving about 11mm.
As regards the Aura 1808, the radially polarized gap is about 2" long, and the coil is underhung. It does have a real x-max of 3/4" (18mm).
Drivers like the TC Sounds are a different kettle of fish. Being overhung they are less efficient, about 7dB~9dB less than the PA drivers under discussion (not to mention tipping the scale at over 45 pounds). I'm sure they can handle the 3KW they're rated at for car stereo 'burps' and typical home theater use, but if you try that kind of power long-term at a dance party I think you will be in for a surprise.
Xciterking said:
All I can say is what I said previosly - the 2242's in the horns are extemely low compromise. I could probably write a 5 page of 'review' of audiophile superlatives 😉 but that kind of stuff gaggs me- I've built/owned many bass systems and this is the one I listen to below 80 cycles and have not had the urge to replace - ever. It's a fact it will 'keep up' (low compression, high efficiency, low distortion) with any horn speaker system that will fit in my room.
djk said:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Meet the WOOFER-BUNNY !!🙂
All the drivers discussed are good, with the possible exception of the 2241, it has mechanical damage issues.
The 2268 Kris. It is the superior driver, comparable only to the Aura/Seismic (very expensive) and the upcoming TC.
Be prepared for some serious bass when your intermission hip-hop comes on. You won't bottom these like that. You'll see 😉.
Cheers,
AJ
"Looking at the impedance plot of the VT4880A sub which employs the 2269, it appears that this design is in fact a sealed enclosure."
Blind as a bat, I see. The impedance plot shows a vented box with an impedance minima at ~29hz and the traditional double hump, the upper one ~53hz and the lower one around 15hz.
Ohh, you say? The plot cuts of at 20hz? How do you know?
The same way I know the other things I have expressed. The clues are there to someone with more experience.
Blind as a bat, I see. The impedance plot shows a vented box with an impedance minima at ~29hz and the traditional double hump, the upper one ~53hz and the lower one around 15hz.
Ohh, you say? The plot cuts of at 20hz? How do you know?
The same way I know the other things I have expressed. The clues are there to someone with more experience.
I love these TC speakers http://www.tcsounds.com/news_pa.htm
http://www.tcsounds.com.unixweb-7.nethere.net/padrivers.htm
I think I will send back my LW1400's and get two of these. I wish I had a fix on them just a little earlier.
http://www.tcsounds.com.unixweb-7.nethere.net/padrivers.htm
I think I will send back my LW1400's and get two of these. I wish I had a fix on them just a little earlier.
In my experiance long excursion, low efficiency drivers like the TC sounds are prone to power compression and high distortion (poor sound) . I don't see those specs at the website linked.
High efficiency drivers (like JBL 2242) loaded in a horn is a whole different animal. It would take like 16 of the TC sound 15" woofers to equal the output of one of the 2242's in a corner horn - Xmax means little when you are @ 106 db with a watt in a horn.
It's been said for decades the longer the stroke and cone movement the higher the distortion. Also think about all those 'watts' being lost with the TC' low efficiency conversion - heat & compression are bad not good.
High efficiency drivers (like JBL 2242) loaded in a horn is a whole different animal. It would take like 16 of the TC sound 15" woofers to equal the output of one of the 2242's in a corner horn - Xmax means little when you are @ 106 db with a watt in a horn.
It's been said for decades the longer the stroke and cone movement the higher the distortion. Also think about all those 'watts' being lost with the TC' low efficiency conversion - heat & compression are bad not good.
I have decided to just keep the Eighteen Sound LW1400's for today. I'm up early today to go out there and install one in one of my cabs and hook up the system to hear for myself the difference between (at least) the 2241G and the LW1400 in person. People were telling me that the LW's are installed in some of the high end EAW's. Might not be true, crossing my fingers. I will take some pics to post later today. I’m just not sure if I like the looks of these things. They are very large; I must be used to JBL.
Another engineer called last night and has offered up two 4718's with covers in perfect condition for $1000. I might just get those also, leave no doubt of satisfaction. Then if I like the LW's that much, I could pick up a couple more, grabs some power and Walla, case closed. Thanks for all of your help guys!
🙂
Another engineer called last night and has offered up two 4718's with covers in perfect condition for $1000. I might just get those also, leave no doubt of satisfaction. Then if I like the LW's that much, I could pick up a couple more, grabs some power and Walla, case closed. Thanks for all of your help guys!
🙂
23mm is not impossible:
More info: http://www.jblpro.com/pressroom/VT4880_06/VT4880_06.htm
An externally hosted image should be here but it was not working when we last tested it.
More info: http://www.jblpro.com/pressroom/VT4880_06/VT4880_06.htm
Ho-hum, another driver with no datasheet.
The only thing they say about that driver is that it can move 1-3/4" one-way before something slams into the frame or magnet.
As regards the 2268:
I really don't care, if you want to believe the bogus numbers, go right ahead.
I will stand corrected when you have a JBL engineer e-mail me with the gap height and coil lengths.
JBL claims 23mm x-max on the 2268H in their line listing of T/S parameters. If you look closely the other two drivers with the same basic motor are only 8mm and 11mm respectivly. The 8mm driver is the same efficiency as the 2268, the other is lower efficiency, hence the longer x-max (it also has higher Le than the 2268 indicating a longer coil,m and az higher Bl, indicating a longe coil too). On a line right above that is a driver with the efficiency listed as 700%, I suppose he believes that too.
JBL has not published a full data sheet on these drivers, so we don't really know. But the Le and Bl tell the story in their own way, as does comparing it with its siblings.
The completely different W15GTi has two 0.5" gaps, and two 1.3" coils. The x-max claim of 0.8" is proven by these measurements. The W15GTi needs over 3KW to make it hit its x-max. Its only 92dB/2.83V, and its 3 ohms, so it is 87.74dB/W/1M
The 2268 is 2.8% efficient, that's 96.5dB/W/1M
Do you suppose it's almost 9dB more efficient because it has a much shorter coil?
No such thing as a free lunch.
Again, I will stand corrected when you have a JBL engineer e-mail me with the gap height and coil lengths (like they provide for the W15GTi).
The only thing they say about that driver is that it can move 1-3/4" one-way before something slams into the frame or magnet.
As regards the 2268:
I really don't care, if you want to believe the bogus numbers, go right ahead.
I will stand corrected when you have a JBL engineer e-mail me with the gap height and coil lengths.
JBL claims 23mm x-max on the 2268H in their line listing of T/S parameters. If you look closely the other two drivers with the same basic motor are only 8mm and 11mm respectivly. The 8mm driver is the same efficiency as the 2268, the other is lower efficiency, hence the longer x-max (it also has higher Le than the 2268 indicating a longer coil,m and az higher Bl, indicating a longe coil too). On a line right above that is a driver with the efficiency listed as 700%, I suppose he believes that too.
JBL has not published a full data sheet on these drivers, so we don't really know. But the Le and Bl tell the story in their own way, as does comparing it with its siblings.
The completely different W15GTi has two 0.5" gaps, and two 1.3" coils. The x-max claim of 0.8" is proven by these measurements. The W15GTi needs over 3KW to make it hit its x-max. Its only 92dB/2.83V, and its 3 ohms, so it is 87.74dB/W/1M
The 2268 is 2.8% efficient, that's 96.5dB/W/1M
Do you suppose it's almost 9dB more efficient because it has a much shorter coil?
No such thing as a free lunch.
Again, I will stand corrected when you have a JBL engineer e-mail me with the gap height and coil lengths (like they provide for the W15GTi).
Look what I found:
Re = 5.3 ohms
Fs = 33 Hz
Qts = 0.36
Qms = 3.8
Qes = 0.39
Vas = 328 liters
no = 2.8 %
Sd = 0.1269 sq m
Mms = 168 grams
Bl = 21.5 T*m
Pe = 800 W
Xmech = 23 mm (spider bottoms on gap sleeve)
(Still no spec for x-max though)
Re = 5.3 ohms
Fs = 33 Hz
Qts = 0.36
Qms = 3.8
Qes = 0.39
Vas = 328 liters
no = 2.8 %
Sd = 0.1269 sq m
Mms = 168 grams
Bl = 21.5 T*m
Pe = 800 W
Xmech = 23 mm (spider bottoms on gap sleeve)
(Still no spec for x-max though)
DJK,
I'm surprised you're still wasting your time with this. The 23mm xmax is obviously an error, probably an error by a secretary entering technical data instead of an intent to mislead. You've already explained quite well why it must be an error and even pointed out another typo in the same listing. You tried, but "You can lead a horse to water...".
I'm surprised you're still wasting your time with this. The 23mm xmax is obviously an error, probably an error by a secretary entering technical data instead of an intent to mislead. You've already explained quite well why it must be an error and even pointed out another typo in the same listing. You tried, but "You can lead a horse to water...".
At the risk of repeating myself:
"The only thing they say about that driver is that it can move 1-3/4" one-way before something slams into the frame or magnet."
"I'm surprised you're still wasting your time with this. The 23mm xmax is obviously an error, probably an error by a secretary entering technical data instead of an intent to mislead. You've already explained quite well why it must be an error and even pointed out another typo in the same listing. You tried, but "You can lead a horse to water..."."
John, you're absolutely correct. I've sent JBL some mail as regards this, we'll see if they reply.
"The only thing they say about that driver is that it can move 1-3/4" one-way before something slams into the frame or magnet."
"I'm surprised you're still wasting your time with this. The 23mm xmax is obviously an error, probably an error by a secretary entering technical data instead of an intent to mislead. You've already explained quite well why it must be an error and even pointed out another typo in the same listing. You tried, but "You can lead a horse to water..."."
John, you're absolutely correct. I've sent JBL some mail as regards this, we'll see if they reply.
I wouldn't expect a reply if you used the same pugnaciousness tone you're using here.
The whole thing is puzzling, though.
I've never seen an accordian suspension with as much excursion as they're claiming.
I wonder if by x(mech) they mean x(sus), which is a measure of suspension stiffness nonlinearity, not max mechanical excursion.
The whole thing is puzzling, though.
I've never seen an accordian suspension with as much excursion as they're claiming.
I wonder if by x(mech) they mean x(sus), which is a measure of suspension stiffness nonlinearity, not max mechanical excursion.
djk said:
Yes but will you believe them when they tell you that the xmax is 23mm ?
I don't know what the problem is here, JBL is not known to fudge the numbers. I have used them for years.
The differental drive system that JBL developed is a bit different from the conventional.
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