After a suggestion by
and the discussions regarding the discontinuation of the Infinity that take place at the Infinity thread
, it was decided that there was a need for an official JBL CS1214 thread. The JBL seems to be the closest driver to the Infinity we can now get for around the same money. It can be bought for around 43USD in the US, 35-45GBP in the UK, 50-65 Euros in Germany.
This is a new thread regarding a driver that has not been used extensively yet so the thread will be updated continuously. I hope everyone can contribute to this thread so we can gather all the information we all need. I am quite new to this and not an experienced DIYer or technical person, so whenever someone has anything to contribute we would all appreciate it. A lot of thanks go to
for all their help in my original thread.
Links to new builds, your measurements etc are always welcome.
While the JBL seems to be the closest alternative we now have, there are some differences that are worth mentioning.
The Xmax of the driver is 12.1mm overhang. As LTD02 explains "a typical value for xmax is overhang plus about 1/3 of gap, so about 14.7mm. The next stop would be 'usable' which might include another 1/3 of the gap, so about 17.3mm. The next stop would be where the coil leaves the gap, which would typically be xlim (assuming nothing else is happening such as the spider meeting the top plate or the former striking the back plate), which would be about 19.9mm.
For modelling... use about 15mm and if it went over by a couple mm that would be fine...something around 500 nominal watts for a home theater application. 250w is probably the safer bet for extended music blasting."
This is for a sealed configuration in a 50L box.
Fs: JBL is 28hz, Infinity is 23.5hz.
Vas: JBL is 76.6L, Infinity is 82.96L
I managed to find some distortion graphs of the driver from a German home theatre forum. They seem to praise the driver for what it costs. I am not sure if I am allowed to upload the graphs and/or provide links to the forum. If yes, I will upload and reference as required. Any input on this is appreciated.
Personally my original plan was a Full Marty, but after consideration I thought that 8 nearfield were the better choice for my needs. 4 drivers in series-parallel will be wired on each channel on an inuke 6k
Based on what I have gathered and the WinISD models, multiple 12' JBL enclosures would have multiple advantages over the Ultimax. More air will be moved, possibly more dbs depending on the speakers and power, more flexible positioning (can also act as TV/Speaker stands), more db room gain due to multiple subs, better response due to multiple speakers, more extension when going with sealed, and easier to build. Stacking them would also produce more db gain.
Here are some models of sealed drivers for comparison. These are with a frist order high pass @ 10hz to simulate the inuke 6k roll off.
Orange: 4 and 8 JBLs in 50L boxes, Qtc 0.704, Ql 10, Qa 4. Xmax @ 21hz, 380w per driver
Yellow: 4 and 8 Infinity 1260w in 37.5L boxes, Qtc 0.705, Ql 10, Qa 100. Xmax @ 20hz, 395w per driver
Green: 1 and 2 UM18-22 in 200L, Qtc 0.706, Ql 10, Qa 8. Xmax @ 17hz, 1340w per driver.
As you can see both the JBL and the Infinity have an advantage over the sealed UM-18. The models have also been spot on when eng-399 tested the drivers, which is a good thing. Following are the two test he has completed so far comparing the JBL to the Infinity and to everyones surprise, the JBL is louder than the Infinity!
Thanks go to eng-399 for letting me post his measurements. Purple line is the JBL and green is the Infinity 1260.
In addition a test was completed to compare the 1.7cf to a 1.3cf box before driver and bracing. Needless to say the the bigger box has an advantage.