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lgvenable
08-06-2007, 03:13 PM
I'm having troubles finding the spec's for a E-155 for winisd. I've searched high and low and haven't it yet.

second: after searching for several hours I've seen several sub boxes, like the 4546C, and the synthesis SIS-EX, as well as the article from 1983, and another drawing from the time period. I'll post the links to those .

links to what I found:

http://www.audioheritage.org/vbulletin/showthread.php?t=4238&highlight=S1S-EX+enclosure
http://www.audioheritage.org/vbulletin/showthread.php?t=17702
http://www.audioheritage.org/vbulletin/showthread.php?t=17373&highlight=2245
http://www.lansingheritage.org/html/jbl/reference/technical/1983-subs.htm
http://www.audioheritage.org/vbulletin/showthread.php?t=7550&highlight=2245
http://www.audioheritage.org/vbulletin/showthread.php?t=10210&highlight=diy+subs

and I might have left a couple out....


However I wanted to build a sub box; on the order of the 4546C, and wondered how a E-155 might perform in such a box, however wanted to know if I should go for a reconed E-155or go upscale and get a 2245H driver.

Finally wasn't it Giskard that built his synthesis with 3 x 6" ports, however what length were they?

Last but not least; and since I'm a chemist; I'm not too ashamed by this question, as I only pick up the requisite electronics to complete a project (we've got lots of EE's where I work if I get stuck..but right now they are all in China)

--> how do I tune the port; I'm assuming I need a frequency analyzer; meaning after building the monster box, I need to take it to a hi end HIFI shop and have the port tuned?? Is that correct?

Hopefully that last statement wont get me flamed :D

speakerdave
08-06-2007, 05:12 PM
I'm having troubles finding the spec's for a E-155 for winisd. I've searched high and low and haven't it yet.

second: after searching for several hours I've seen several sub boxes, like the 4546C, and the synthesis SIS-EX, as well as the article from 1983, and another drawing from the time period. I'll post the links to those .

However I wanted to build a sub box; on the order of the 4546C, and wondered how a E-155 might perform in such a box, however wanted to know if I should go for a reconed E-155or go upscale and get a 2245H driver.

Finally wasn't it Giskard that built his synthesis with 3 x 6" ports, however what length were they?

Last but not least; and since I'm a chemist; I'm not too ashamed by this question, as I only pick up the requisite electronics to complete a project (we've got lots of EE's where I work if I get stuck..but right now they are all in China)

--> how do I tune the port; I'm assuming I need a frequency analyzer; meaning after building the monster box, I need to take it to a hi end HIFI shop and have the port tuned?? Is that correct?

Hopefully that last statement wont get me flamed :D

You seem to suggest that your e155's are such that you would not mind using them as cores for reconing. If that is true, then have 2245 recone kits put into them; you can do that because the frame and motor for the e155 and the 2245 are the same. Be sure you are getting genuine JBL factory recone kits, not aftermarket. Then you can follow the 1983 article describing the box for the 2245. If you copy their dimensions and construction methods carefully enough maybe you can avoid having to specifically tune your enclosure(s).

David

lgvenable
08-06-2007, 06:41 PM
Actually I had found one newly reconed as a e-155, how would it perform??

speakerdave
08-06-2007, 06:44 PM
Actually I had found one newly reconed as a e-155, how would it perform??

As a hi fi subwoofer, very inadequately.

David

subwoof
08-06-2007, 07:13 PM
LF specs for the E155 in 2 different JBL factory boxes can be found by looking up the data sheets:

G718 ( first generation "G" series )

4695 ( first generation cabaret series )

I found the raw drivers to be excellent choices ( back when there were few ) for nightclub sub cabinets when they also were utilized as dance stages..

The 2240's and 2245's had suspension issues and if not rotated, died early.

One PSA2 and (4) E155's did a lot for a modest budget back then.

sub ( and I don't mean teacher )

lgvenable
08-07-2007, 06:17 PM
OK
Then it sounds like a recone to a 2245 is necessary; then it should be a drop in to make a DIY 4645C
L

lgvenable
08-07-2007, 06:20 PM
Dave
so if I need to tune the sub, or want t check the box after build, I need to use a frequency analyzer?? to complete the task.
L

speakerdave
08-07-2007, 07:03 PM
OK
Then it sounds like a recone to a 2245 is necessary; then it should be a drop in to make a DIY 4645C
L

No, because the 4645C uses the 2242, which you don't have. If you get 2245's, follow the 1983 article.

David

speakerdave
08-07-2007, 07:06 PM
There are some E155 parameters on this website:

http://www.thielesmall.com/database.asp?diam=Select&type=0&brand=JBL&use=0&feat=0&prod=0&form=0&order=X

David

speakerdave
08-07-2007, 07:12 PM
There are dimensions, though no port/duct information, of an E155 PA subwoofer here:

http://www.lansingheritage.org/images/jbl/catalogs/1982-pro/page09.jpg

The specs say the "range" is down to 30 Hz; I would be willing to bet that is a 10 dB down point. The box is about 10 cu ft.

David

speakerdave
08-07-2007, 07:27 PM
Dave
so if I need to tune the sub, or want t check the box after build, I need to use a frequency analyzer?? to complete the task.
L

If you get 2245's and follow the 1983 article you may be able to build without specifically tuning your enclosure (after all, that's one of the assumptions behind the article). Varying construction methods can lead to differing system losses and varying driver performance can lead to different results, so a testing/tuning set up is nice to have. I would proceed without that first and see if the results were satisfactory. If you build a cabinet using the recommmended materials and methods, particularly for bracing, you should be all right. If you use new drivers or new recones there will be a break-in period. Build the enclosure as described and use it for a few months, then consider where you are and go from there. The 1979 Enclosure Manual will give you a good basic foundation in building technique:

http://www.lansingheritage.org/html/jbl/plans/1979-manual.htm

If you decide to get into testing stuff, there are various software/hardware packages for computer which make it cheaper than buying a shelf full of electronic test equipment. I'm not familiar with them because I don't have a WinTel computer.

David

lgvenable
08-08-2007, 12:24 PM
I'm having the E155 reconed w/JBL to a 2245H; after all its only money right; and we can't take it with us...

the discontinued 2245H recone kit > 300.00 ouch! Thanks JBL

At any rate it's being turned into a 2245H

L

speakerdave
08-08-2007, 06:12 PM
I'm having the E155 reconed w/JBL to a 2245H; after all its only money right; and we can't take it with us...

the discontinued 2245H recone kit > 300.00 ouch! Thanks JBL

At any rate it's being turned into a 2245H

L

Good show.

You might be money ahead to sell it--don't know what you paid for it nor exactly what you could get for it, but it's certainly a good bass guitar speaker. JBL pro still has the 2245 for about $525 (just went up).

David