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View Full Version : Help with JBL 2440/1 Horn Choices



Joe Alesi
05-18-2007, 09:31 PM
Hello All,

I hope everyone is happy and well.

I am in the middle of building up a JBL 4560 (fitted with 2226) +2440/1 +2403 + sub for a large room at home. I would like you opinions on some possible horn alternatives for the 2440/1. I haven't got the time to devote to building a beautiful walnut 9800 horn:applaud: unfortunately, so I would like to ask your opinions on your preferred choice of these horns:


1. JBL 2350 (available to me in Australia for US$200+)
2. JBL 2385 Copy (actually not quite a copy- it is some 10-20% larger, but has similar dispersion pattern) (already have these)
3. Altec 2x5 Multicell + mods to fit 2440.( I could get these for US$150 or swap for two 2401 tweeters- without diaphragms) and then try to make or mod the throat/adapter

Your thoughts on the best choice?

Thanks in advance

Best
Joe Alesi

Joe Alesi
05-22-2007, 03:03 PM
Now word yet boys?:D Oooops ....Gals as well.

grumpy
05-22-2007, 04:03 PM
... think I'd go modern, unless you just like the 2350 (I do... outside)

Zilch
05-22-2007, 04:47 PM
More, from Eargle & Foreman:


The main performance problem with the multicells is their tendency to "finger" at frequencies above 2 kHz. Note that the fingering covers a 10-dB range at the highest frequencies and as such is quite audible. Today, multicells are likely encountered only in older installations, and they are rarely specified in modern design projects.

Joe Alesi
05-22-2007, 05:13 PM
Hello Grumpy and Zilch,

Taking both your opinions into account- I think it's option 2: my JBL 2385 "copy" (+~10%).

Size comparison

Size-----JBL 2385A-----JBL 2385 Copy+10%
Width____445mm_______472mm
Height____279mm_______295mm
Depth____236__________240mm

What do you think? I suppose the extra size might buy me a tiny bit more LF cutoff. My plan would be to try and use them as low as possible ~500Hz. By the way I can't find a 2385 datasheet- only a 2385A- any pointers on that or any differences between the two?

Best
JA

Joe Alesi
05-22-2007, 05:24 PM
Hello Grumpy and Zilch,

Taking both your opinions into account- I think it's option 2: my JBL 2385 "copy" (+~10%). What

Size comparison

Size-----JBL 2385A-----JBL 2385 Copy+10%
Width____445mm_______472mm
Height____279mm_______295mm
Depth____236__________240mm

What do you think? I suppose the extra size might buy me a tiny bit more LF cutoff. My plan would be to try and use them as low as possible ~500Hz. By the way I can't find a 2385 datasheet- only a 2385A- any pointers on that or any differences between the two?

Best
JA

grumpy
05-22-2007, 06:36 PM
Hey Joe,

been wrong before, but I believe the differences are not related to the
horn function... backside differences, perhaps cost to manufacture?

If you have the flexibility to try a crossover frequency a bit higher than
500 Hz, you should try it and see what you think... I know what the spec
says :).

-grumpy

johnaec
05-22-2007, 09:15 PM
By the way I can't find a 2385 datasheet- only a 2385A- any pointers on that or any differences between the two?As far as I know, JBL only changed the external throat configuration between the two. The original 2385 hand a much thicker and "cylindrical" exterior where the throat part of the horn meets the mounting flange, and on the 2385A they made this thinner and switched to support gussets to make up the strength, which apparently didn't work as well as hoped - there have been numerous reports of all the "A" series cracking in that area. If a support is made for the driver, you shouldn't have this problem: http://audioheritage.org/vbulletin/showpost.php?p=168507&postcount=12

I assume you're aware the 2385 series have a dispersion pattern of 60x40 degrees? Some would consider this a little "tight" for home use. But if you're interested, I do have some actual JBL 2385A horns in mint condition I'll sell for $50 each.

John

Joe Alesi
05-23-2007, 03:47 AM
Hello Grumpy and John

Thanks for your responses.

Grumpy- I hear you saying you prefer the 2440/1 played up higher than 500Hz. Are you saying perhaps 800- I was considering this and it will be easy to do as I will go active. Only issue would be running the 2226 up to 800 (which is normally fine), but I would be using it in a 4560 enclosure.

John- I appreciate the offer and certainly if you were local I would have already bought them from you since they are the genuine article. But my existing ones are close so I will try them first. Yes the 60 x 40 is TIGHT- it should be interesting. Mine have a slightly wider mouth- this may help a little, but I'm not hopeful.

Best
JA

grumpy
05-23-2007, 06:37 AM
up to 800Hz, yes... that was my intended suggestion that you try for yourself. -grumpy

Steve Schell
05-26-2007, 08:03 PM
Hi Joe,

I have always preferred midrange horns with larger mouths and lower cutoffs as a general rule. They are capable of generating what I call "big goose bumps" vocal reproduction, the sensation of Louis or Ella standing in front of you.

Most of the polar plots I have seen of large multicellular horns show the onset of serious fingering only above 6 or 7kHz. This worked out in the old days (1930s and 1940s) as they didn't seek to reproduce higher frequencies anyway. These days we usually cross to a tweeter, so it still is not an issue. I used a variety of huge old 300Hz. multicellulars in my living room system for years and never found fingering to be a problem. Perhaps it is a different story in a theatre when measuring 50 or 100 feet out with an RTA.

Of the horn choices you listed, I would tend toward the 5x2 horn, especially if it is a 1003 rather than a 1005. I have run 288s with 6dB/oct. passive crossovers on 300Hz. horns without blowing them up, but of course this was at living room hi fi levels. You could build throat adapters to fit the 2440s to the Altec horns; a friend once built some very suitable custom adapters from fiberglass resin and cloth.

Mr. Widget
05-26-2007, 08:31 PM
I have always preferred midrange horns with larger mouths and lower cutoffs as a general rule.I agree 100%

Alternatively, if you don't have a large horn, cross it over at a higher than recommended frequency. For example the "800Hz" 2397 sounds better when crossed over above 1000Hz.


Widget

Tom Brennan
05-27-2007, 09:44 AM
My experience with multicell horns, tar-filled Altec 1005s on 288s, was VERY good. They sounded open and effortless and made wonderful vocals. This fingering thing may be more a theoretical problem than a practical one, at least in hi-fi applications.

Note too that the move away from multicells must have had cost benefits for manufacturers, I can't think of a more expensive way to build horns, replacing a tin-knocker with a mold has to be cheaper.

Joe Alesi
05-28-2007, 05:55 AM
Hi Joe,

I have always preferred midrange horns with larger mouths and lower cutoffs as a general rule. They are capable of generating what I call "big goose bumps" vocal reproduction, the sensation of Louis or Ella standing in front of you.



Hello Steve,

WHAT AN INCREDIBLE THING TO SAY: A few months ago I reported on our March 2007 Melbourne Audio GHuild meetting. Here is what I said:

OK Guys report on this GTG:

SUPERB

FANTASTIC

INSANE DYNAMICS_ SOME OF THE BEST MOST DYNAMIC SOUND I HAVE HEARD

ELLA AND LOUIE WERE THERE LAST NIGHT- yes I mean there. The dynamics WERE 90-95% ( I choose this figure VERY VERY VERY carefully) of that of a live performance amplified through the loudspeakers. The imaging was also good and you could hear deep into the sound stage. Through some music I just sat there and smiled- this is it- the end of the road- look no further. WAF- forget about it. Get the idea I liked it?

Well last night we listened to a 3 way ALTEC/JBL horn system: coutesy of Russell and Peter. They did lots of set up work on the day prior to the evening. Steve from Reference Audio Visual was kind enough to measure the system response through the DEQx. Sure it wasn't perfect, paticularly in the mid bass, but 500 Hz and up it was very flat with good HF extension. There was a bump in the bass at around 60-80Hz, but we lived with that and it was evident and detracted somewhat (1%) from some of my fav. recordings.


Bass: 15inch Altec 515 driving a front bass horn, with porting,
Mid: 500 hz to about 12kHz Altec 288 Compression driver driving a 8 cell Altec Multicellar Horn (read large)
Trebele: 12kHz upwards JBL 2405 Slot loaded horn tweeter

Amplification varied from the Varkeylabs Single ended valve power amp to a 6BQ8 push-pull valve amp. CD player(transport) was a Cambridge CD2 feeding a EAD DAC and Power Supply or alternatively the Altman spruce board DAC. the Preamp was a DIY valve amp.

Dynamics were way beyond the capabilities of commercial offerings- You would need to spend LOTs (I mean L O T S) to even approach these dyanmics. Sorry Guys- this time you missed it- the holy grail (or part of it atleast) was on demo.

Yes I havve pictures on my phone(!!!!????###), need to find my download software.
EDIT:
Done- excuse the image quality from my phone, ome good some not so good....the shutter is on a mega lag and uses a very slow speed.

Buy the music pictured it sounds great. One for you too Amfi...ahhh...Kieth. Some OT photos aswell from the night before at the motorshow.

Best
JA

Sorry for the long post- I can add photos later?

Also thanks to Steve, Mr Widget and Tom for your responses.

Looks like I need to get the Altec Multicell and build a new throat to suit the 2441. Does anyone think this will be an unholy alliance (better/same/worse???) compared with using a 288?

Thanks in advance,

JA

hjames
05-28-2007, 06:05 AM
Hello Steve,

Buy the music pictured it sounds great. One for you too Amfi...ahhh...Kieth. Some OT photos aswell from the night before at the motorshow.

Best
JA

Sorry for the long post- I can add photos later?

Very cool - always interested in new horn knowledge.
You can edit your posts within 24 hours of their first post - upload pictures as well as long as its in that window. And please - let us know what albums you referred to ...

Earl K
05-28-2007, 06:16 AM
Hi Joe,

- Based on your own experience with 288s & multicells / I would encourage you to grab the pair of multicells available to you. ( One reason for this, is that to duplicate what you heard & reviewed , you'll eventually want to own a pair of Altec 288 drivers ) . BTW; What model 288 was reviewed ?

- You'll need to make a pair of entry adapters / a la the Dukane 2" type. These were used to enter into VitaVox multicells ( OEMed in N.A. for Dukane ) .

- I would also encourage you to stick with 2440 diaphragms ( instead of 2441s ) since you're using a tweeter above the mid horn .

:)

Joe Alesi
05-28-2007, 06:30 AM
Hello Guys and Gals,

Some more Pics. (Not bad for a mobile phone camera!)

Best
JA

Joe Alesi
05-28-2007, 06:38 AM
Hi Joe,

- Based on your own experience with 288s & multicells / I would encourage you to grab the pair of multicells available to you. ( One reason for this, is that to duplicate what you heard & reviewed , you'll eventually want to own a pair of Altec 288 drivers ) . BTW; What model 288 was reviewed ?

- You'll need to make a pair of entry adapters / a la the Dukane 2" type. These were used to enter into VitaVox multicells ( OEMed in N.A. for Dukane ) .

- I would also encourage you to stick with 2440 diaphragms ( instead of 2441s ) since you're using a tweeter above the mid horn .

:)

Hello Earl,

I think you are right- buy the Multicells. Sorry I'm no Altec expert- but they were the ceramic magnet version 288, which is a 288C- I think???? What do you all think- Better than the 2440 or 2441? Or is that too controversial to ask:D.

PS: Heather- I have posted PICS of some of the CDs and Albums played. I am still trying to hunt down which Louis and Ella was played- I was so gobsmacked I forgot to get a PIC of the cover.

PSS: there is a Lansing Heritage Forum Australian Member pictured in one of the pics. I cannot reveal who because he has not signed his modelling release. :D:D Maybe he can ID himself if he chooses to.

Best
JA

Earl K
05-28-2007, 06:57 AM
Sorry I'm no Altec expert- but they were the ceramic magnet version 288, which is a 288C- I think????

- A ferrite ( ceramic ) magnet means it was either a 288-8K or 288-16K ( different impedance diaphragms ) .


What do you all think- Better than the 2440 or 2441?

- I consider the Altec 288-8K ( which I have here in my front room ) to be one of the easiest to listen to compression drivers, available . Its' characteristics of diaphragm damping are just right for my ears .
- JBLs' SR offerings ( meaning any diaphragm without a coating of aquaplas , put out too many obvious diaphragm resonances for my liking. I just can't hear past these resonances to get to and then enjoy the music. Mind you, I also hear capacitor resonances that I must damp down by dc-biasing ( Charge-Coupling ™ ) pairs of caps.
- I guess it all depends on what ones' ears are sensitive to when making these choices .

BTW ; I use 3" diaphragmed 2431Hs and 1.75", 2426H drivers on an almost weekly basis in my SR work. My 4" diaphragmed, 2440 and 41s and 82s are retired for the time being.

Steve Schell
05-28-2007, 12:21 PM
Joe, what can I say? I guess great minds think alike. I enjoyed your enthusiastic review.

My fascination with large midrange horns began in 1991, when I built a pair of square cross section 150Hz. exponential horns from masonite. Being unhampered by knowledge, I made the mouths 28" square and took the throats down to 1" diameter for use with 802C drivers. With such long slender throats they beamed horribly, and required locking one's head in a vise for stable imaging. Nevertheless they had body, tone, and that "they are here" believability to vocals. I later chopped them to a 1.4" exit for use with 288s, which worked better.

Most hi fi speakers compress dynamics horribly. Since beginning with the horn stuff I've never looked back. Sure there are challenges of size, horn colorations, time alignment and all the rest, But I'd rather improve on these as best I can (or tolerate them) rather than live with a speaker that muffles dynamics. I think this is why the A5 and A7 systems have become such a test bed for DIY experimentation; despite their flaws they do preserve dynamics quite well.

kalkan0
05-31-2007, 01:43 PM
Hello Joe,

I advise you an iwata horn like on my system, expensive but the sound is great !
I have seen a 2385 on ebay europe, in a box of wook filled with sand . That would be also a good solution
http://cgi.ebay.fr/2-Pavillons-JBL-2385-2-pouces_W0QQitemZ200114293908QQihZ010QQcategoryZ137 944QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Have a look on my system http://kalkan0.free.fr/
Sincerly Maurice
http://kalkan0.free.fr/mes%20images/JBL4560COTEpetit.jpg

Joe Alesi
06-01-2007, 03:48 AM
Hello Maurice,

Thankyou for your response. I like your 4560- nice work. I have some copy 2385 type horns (although about 10% bigger). I like the sand filled box method- that way you can re-use the horn, which is not easy if you use something like concrete or plaster.

Would you say the Iwata horn would be close to the JBL 2350 in sound/dispersion?

Best
JA