EN3's to rethink...

[Nightbrace]

I have decided to sell my L200B's and want to put my EN3's back into more regular use...

Currently they have:
LF>2203H woofers (they are actually the sonic equivalent to the 121H's now as the correct kits are no loger available) (Hopefully I'm good here )
HF>2420/2312/2308 (how does this combo compare to the LE85/H92/L92 combo)
UHF>2404's (which do not fit properly, but are mounted on the outside of the cab.) They do not sound too bad... but I'd like to get UHF transducers that will physically fit in the opening... So they are officially up for sale.. PM me if interested... 075/2402's are on the top of my list thus far, but am wanting more info about the 076/2403's and 077/2405's which should both physically fit to make a better decision. There are 2402H's with 2405H diaphrams on Ebay that I am contemplating trying, what you guys think?

http://cgi.ebay.com/2-JBL-2402H-05-b...QQcmdZViewItem

Networks, um, well the short of it, they need to go, were put together (not by me, so I cannot take the blame) just to get the tweeters working in their usable frequency range.. and I need to start from scratch and sell them, they are from the 4331's which I bought as donors.

My question is what JBL Network will work for this combo, assuming I decide to go with the 075 UHF transducers? Or must I build something from scratch?

[Zilch]

Musta been tough gettin' those 2312s in a cabinet that's only 12-17/32" deep....

[Nightbrace]

I was thinking the same as you are, but they do fit. These are the horns JBL called for with these cabs..

http://www.lansingheritage.org/image...pro/page13.jpg

[Zilch]

2420 pokin' out the rear, is it?

[14-5/8" INSIDE depth required on 2312.... ]

[duaneage]

Would that be like "Woofer in front and poking in the rear"

[Nightbrace]

LOL, thought I fooled ya, there's a cutout in the back to accomodate for them..

[Nightbrace]

Hmm, why not just use the LX30 networks, but then won't then sound more like the Jubals?

[Zilch]

Something you did, or they came standard that way?

Again, how 'bout some pics....

[Nightbrace]

I will!, they came with a removable opening for these from the factory, or so it looks.. Pics on the way. No more 2404's though, already removed as are the crossovers.. I'll be listing them for sale here soon along with a lot of other JBL goodies that I don't need including those L200B's.

Spent the past day going over all the specs and reading through the old JBL literature.. 077/2405's are going in... Seems as if I'll have something similiar to the L300 when I'm done.. Not too sure if the LX30 networks will work well enough though with the 2420/2312/2308 combo. Won't I need to use a 16 Ohm L-pad?



Hmm, what about these "upgraded" N333 Networks for my EN3's?? I may have to do some tweaking with the LF section though... although not too far off as all I'd have to do is remove one of the 20.0 uF caps in the LF section to duplicate the LX30's, and definitely better than what I have now...



I really don't want to have to go back to the LE5-6's I had now that I got these compression drivers and horns rockin' out, but they would actually sound pretty decent with the LX30's... Decisions, Decisions... I hate to sell those compression drivers and horns as they are so darned hard to find..

[soundboy]

I went through the whole gamut 25 years ago with the 2420 horn/lens thing...they are really fairly common now, especially on ebay, and with the relatively low efficiency of the 2203's, the LE 5 really would be a better choice....the crossover is designed for it, and unless you used a 4333/L300 crossover, and turned the mids and highs WAY back....well, don't mess too much with different drivers and mixed and matched crossovers....the filters are everything...luckily within a year or so of getting my 2312's and 2420's in about 1980...the biradials came out, and I traded them promptly after first listen BTW, are you leaking air out the back around the horn driver, or? I would hold out for a pair of O77's...the 075/2402 doesn't really go any higher then the 2420's, and has VERY beamy response...great for high end on a bass or keyboard amp...but not really hi fi IMNO...

[Nightbrace]

Yeah I agree, not too great for easy listening, I am saving using the 075's for my other project. (a clone C36/C38). Already have D130's and N2400 Networks, so might as well make something cool out of them... What would be the best application for the C36/C38? Maybe to use as keyboard/synth. speakers? Or are they a little more versatile than that?

There is an opening in the back of the EN3's which I filled with more insulation... This isn't too much of an issue. There is a little cutout in the back and its not a big opening... Bass sounds great with the "121H's".

I agree with you about the LE5-6's and didn't want to even mention it as I like the idea of having compression drivers horns and lenses, but it does make more sense for these cabs with the crossovers I am considering and the woofers I am using..

How much you think I could get for the compression drivers/horns/lenses? If I sell them, I could get by really cheap here and have enough money to either build some C36/C38 cabs or find some originals.

Here are the rolloffs from a previous post by Giskard:

" The filter for the 124 slopes off at ~ 6 dB / octave
The filter for the LE5 slopes off at ~ 12 dB / octave
The filter for the 077 slopes off at ~ 18 dB /octave

The voltage drive crossover frequencies with a standard 8 ohm test load are -3 dB at 550 Hz and -11 dB at 9 kHz"

Does this mean I need to buy -6 dB caps, -12 dB caps, and -18 dB caps respectively?

[soundboy]

It would take too much to explain...you're not getting it. I would stick with a purpose designed crossover with the correct drivers. The quotes you listed have to do with the slope of the filters...nothing to do with the values, or frequencies, or electrical/acoustic response, etc....I would do more reading on here, and get an idea of the correct selection of drivers/crossover...everyone has an idea, but the tried and true JBL combo's are a good place to start...somebody already engineered them. I am not at all familiar with the really old stuff past the mid 70's....but, unless you are being sarcastic, I think a C36, looking at the drivers, other than being collectible, would make a great keyboard/synth cab. The value of the horn/driver/lenses is completely dependant upon working and cosmetic condition. Look at the closed auctions on ebay...they are all over the place when it comes to final selling price....good luck and have fun!!!!

[Robh3606]

The filter for the 124 slopes off at ~ 6 dB / octave
The filter for the LE5 slopes off at ~ 12 dB / octave
The filter for the 077 slopes off at ~ 18 dB /octave

124 One pole filter 6db an Inductor in series Low pass

LE5 Two pole filter 12db that is a band pass, band pass means it has two sections made up of a high and a low pass filter. So an inductor and cap in series and a cap and an inductor in parallel.

077 Three pole filter 18db high pass filter a cap in series and inductor in parallel and another cap in series.

Look at the schematic. The number of capacitors and inductors determine the slope. Each cap or inductor adds 6db to the slope and is one of the poles. You need to hit books a bit so you can understand this better

Rob

[Nightbrace]

Thanks Rob, thats what I assumed, thought I needed to order a special type of cap. I think these networks are straight forward enough for a beginner like me, don't you??

Does anyone have the ability to run a bass box program with 121'H's with LX30 networks in these cabs?