JBL 4430 newbie needs some help

[modena]

Hi to all
I live in Athens, Greece and I have purchased a pair of JBL 4430s through an internet ad. Woofers have been recently refoamed... but the suspension feel of one woofer is stiffer than the other one. Excuse my English... what i mean is that if you push the woofer with your hand, the woofer moves back by lets say 3 "clicks", while the other woofer only by 1 "click". Slightly knocking it with a finger, this same woofer sounds "dead", like knocking on something solid and acoustic dead... The other one with the suspension that moves freely, sounds quite different with a live sence of echo. Before I dissasemble the woofer and have it checked / repaired, I thought to ask you guys for some advice. Any input would be much appreciated. I can post photos if these would be of any help. I am really thrilled by their sound, even with this faulty woofer and I am willing to do my best to restore them.
Another thing i need is some plans with dimensions for the covers, as my speakers arrived without covers (and with a lot of scratches on the cabinets)! Can you help?
And a last -silly- question, about the binding posts at the back. I connect bare speaker cable to the lower 2 binding posts. Are these speakers biwirable, so i can use two stereo power amps for vertical passive biamping? Or are the 2 upper binding posts only for active bi-amping with external crossovers?
Many thanks
George

[readswift]

Hello modena! The horn can be sanded and repainted/sprayed, mine are suprisingly good given their age, Im not sure I want to do it at all. There are a few threads here about 443x restoration, you should give the search button a go :) I would be glad if you can document the process with pictures in& out .

[richluvsound]

welcome George,

Active bi-amp only . Bi-wiring is for B&W hifi girls:D
You need cards and a active crossover. What amps are you using ?

Rich

[readswift]

I wont do biamp... setting up remote controlled preamp is insanity. :biting: I think about this bullshlt for 6 months now and not worths my time so I see now... My buddy was right from day 1, I could just fork money out of window. I will just use this 10k ohm ALPS black beauty rotary pot and an active preamp stage going into diy class-a and over. So Im looking for charge coupled 4435 stuff.

[richluvsound]

readswift,

I had my 4435's bi-amped . Not much to gain from my experience. infact there are few posts around here that agree. CC xovers though are a huge up grade having heard Guido's 4435's . But then again ,I'm sure the Nelson Pass influence is not to be ignored .

Rich

[grumpy]

Hi George,

The 2 upper binding posts are only for active bi-amping with external crossovers.
Bi-amping, even with recommended JBL crossover & cards
is ... different. Worth trying if you have the opportunity, but there's
certainly no consensus on which sounds "better". I've gone back to
passive, but mostly because I got tired of flipping all those damn power
switches. ;)

http://www.jblproservice.com/pdf/Studio%20Monitor%20Series/4430LR.pdf

Loose 2235H suspension sounds questionable...

As just measured:
20 11/16" x 21 13/16" ... 1" frame (more in corners to accommodate
mounting holes), 1" thick material. For bevel & back cut (for cloth)
see 4435 plans...

-grumpy

[nrwjbl]

readswift,

I had my 4435's bi-amped . Not much to gain from my experience. infact there are few posts around here that agree. CC xovers though are a huge up grade having heard Guido's 4435's . But then again ,I'm sure the Nelson Pass influence is not to be ignored .

Rich

Hi Rich,

that's really true. Biamping 4435 was ok but did not bring the success I exspected (in contrast to biamping 4343!) But - after implanting Guido's cc-x-overs I'm so pleased with my 4435's and that even without Pass influence.
Maybe I'm on the way installing Pass amps soon.

peter

[modena]

Hello modena! The horn can be sanded and repainted/sprayed, mine are suprisingly good given their age, Im not sure I want to do it at all. There are a few threads here about 443x restoration, you should give the search button a go :) I would be glad if you can document the process with pictures in& out .

Hi readswift.
I've read everything about 4430 in this forum (restoration as well), before I deside to buy them. I will start this project in short time... the only thing that holds me back right now is that I simply cannot stop listening to music! I feel like rediscoveing all my CDs with these speakers. :)
I will post some photos later on...
Thanks for reply.

[modena]

As just measured:
20 11/16" x 21 13/16" ... 1" frame (more in corners to accommodate
mounting holes), 1" thick material. For bevel & back cut (for cloth)
see 4435 plans...

-grumpy

Many thanks grumpy
Any chance you know the kind of blue colour for the cover's cloth? I've seen it in photos, but i was wondering if i could get a more reliable info than judging from a computer screen :) (like Pantone colour or RAL?)

George

[grumpy]

Forum member Zilch actually has a bit of the proper cloth, last I understood...
You might send him a PM. -grumpy

[modena]

welcome George,

Active bi-amp only . Bi-wiring is for B&W hifi girls:D
You need cards and a active crossover. What amps are you using ?

Rich

Hi Rich
Thanks for reply... and thanks for the best comment I have ever heard for bi-wiring :applaud:
I am using BVaudio P1SE preamp + PA300SE power amp, fed by a Benchmark DAC-1. Source is a Mac Mini with AIFF files. What amps are you using?

George

[modena]

This is the current condition of the speakers.

[richluvsound]

Hi George,

they are sweet my friend. They like lots of power. You may want to think about cc networks as an great up grade. If they were mine, I'd try some valves on the top end. (I kinda wish I'd tried that on the 4435's before I sold them.)

My rig :

Mac book, wav file-Panasonic DVD as a transport to Deqx 2.6,to SAC class A mono blocks HF and Alps DIY mono blocks LF. Nakamichi ca 11 pre that I use for a phono pre to a 1200 mk 11
Rich,

[readswift]

yes they are!! Speaking of 4430's I find it incredible there is no translation for what we call in hungarian "masni" and germans call "schleife"
http://www.bastelfrau.de/modules/FCKeditor/userimages/Kopie%20von%20schleife4ohren1.jpg
dictionary gives me only the rather horrid: "loop" .. bow-tie is closer, Is there anything else Rich ?

[readswift]

Rich , I suppose your LF amps supposed to be Pass Aleph's . :)
The ALPS Black Beauty are japanese made (discontinued since) stepped rotary switches , with laser trimmed resistors and feature +- 0.2 dB step error.
They are related to JBL to a degree, too, and occasionally pop up on ebay :

http://www.head-fi.org/forums/1748300-post7.html
whole thread there:
http://www.head-fi.org/forums/f6/alps-black-beauty-148166

[readswift]

Im going to put up pictures of my ALPS BB if there is interest mine is stepped laser trim for real, not fake.

[richluvsound]

yes they are!! Speaking of 4430's I find it incredible there is no translation for what we call in hungarian "masni" and germans call "schleife"
http://www.bastelfrau.de/modules/FCKeditor/userimages/Kopie%20von%20schleife4ohren1.jpg
dictionary gives me only the rather horrid: "loop" .. bow-tie is closer, Is there anything else Rich ?

just bow in english, but french is "ruban" or ribbon . :D

[Zilch]

just bow in english, but french is "ruban" or ribbon . :DTo be more precise, "ribbon bow," as opposed to the one I tie in my shoelaces daily.

[Well, MOSTLY daily.... :) ]

[modena]

Hi all
this is the drawing i came up, based on grumpy's measurements. Can you pls confirm it is correct?
Material would be routed MDF, 1'' thick.

[grumpy]

looks about right. I believe there is a flat region on the edge before the bevel starts,
and a mild (1/32"?) rebate on the back to accept the foldover of the cloth.

See member-provided edge detail:
http://www.audioheritage.org/vbulletin/showpost.php?p=20806&postcount=12

(mine aren't rounded over, but the effect is similar... perhaps there is more than one
version of this minor detail).

[modena]

Today woofers were sent to a specialized JBL repair shop near by. A little "sponge" was missing from the magnet, at the back of one of the woofers... propably stuck somewhwere inside the cone. This was kept for repair... the other one was OK, so I took it back home.

The mid horn, the Alnico 2421A mid driver... a dolphin and a shark that were found inside the cabin :)

[Chas]

a dolphin and a shark that were found inside the cabin :)

Hmm...a JBL aquarium...:D

[richluvsound]

George ,

some may say you lucked out getting 2421a Alnico. I would suggest new dia.
I'm pretty sure you can put an aquaplas Ti dia in there.
Have you sent the serial numbers to HP for the registry ? It's his birthday, it would be a nice little gift for him.

Rich

[modena]

...on Friday evening.
Besides the missig "sponge", the woofer cone was missaligned.
Re-alligned cone and sponge replacement cost was 20 euros. Put the woofer back in place, listen to familiar songs for a while and, yes... the improvement in sound was obvious.
I cann't stop wondering... If 4430s are that much fun, what the 4435s would sound like?
[Rich, i seriously consider your recommendations]

There was snow in Athens during the weekend (!), none went to work today, so I google a bit for cabinet restoration. Lots of people tend to agree on using Howard Restore-A-Finish or Linseed oil. I'll try to find any of these and i will give it a try before i address professioal woodworker.

As for the horns... There are some spots which the previous owner tried to mask using a black marker...
Can you recommend a technique (or the use of a product) that will restore the finish without painting?
In case painting is the way to go, does any one know the kind of synthetic material the 2344 horn is made off?

[jerv]

....

As for the horns... There are some spots which the previous owner tried to mask using a black marker...
Can you recommend a technique (or the use of a product) that will restore the finish without painting?
In case painting is the way to go, does any one know the kind of synthetic material the 2344 horn is made off?

I had the same question a couple of months ago, and was directed to this thread:
http://audioheritage.org/vbulletin/showthread.php?t=1270&highlight=2344

800 grit sandpaper and black vinyl spray paint. I used the same technique, and my horns were as good as new!

[richluvsound]

Hi George.

Try using a bleach based spray cleaner. This removes all grease marks and you'll see the original colour. Its the darkest charcoal grey you can imagine.

PLASTICOAT make a very good MATT BLACK spray MATT, MATT,MATT:)

If you PM Guido , I took him a can to touch up his new speakers. Don't use satin, it looks crap IMO

Rich

[modena]

look much better now, thanks to... ArmorAll Multi-Purpose auto cleaner! It gave a nice deep black to horns and to the black paint on the cabinets. Zilch's grille cloth arrived today (thanks Zilch!), grilles have been routed and meanwhile, all this time i was listening to my favorite music. When the fun factor and excitement gone away, after some critical listening, i found myself wondering...
Where is the bass? Is this all those overpromissing 15" can do?
So... what do I need?
a. A sub
b. 4435s
c. Crown or QSC pro amp
d. ???

George

[readswift]

d = room modes , they should be soffit mount (into the wall) ... Im sorry to burst your bubble, this is the truth. :P

if you dont like wall idea you can try a sealed subwoofer 18Hz - 50Hz but it wont match the sensitivity of JBL's easily .

http://bobhodas.com/pub3.html

[readswift]

maybe you have also some comb filtering going on, opposite phase waves cancel eachother. Im no expert , just a wild guess.
Soffit gives LF extension for sure and not a bad idea to spend on bass traps to stop standing waves (reflection from walls) -> phasing -> frequency irregularities

[mech986]

Hi George,

The absolute first thing to do since the speakers were taken apart for woofer work is to check the polarity of the woofers out of the box, and then check the wiring polarity as you hook them back up. A quick and dirty check would be to switch polarity of ONE speaker at the back jack and see if the bass returns. If so, there is a wiring fault in at least one speaker, best to check both.

Also, its possible if the woofer was reconed they could have been miswired. Check that both drivers, out of the cabinet, will move backward (negative pressure) with positive voltage (1.5V battery) to the RED (non-Black) connector. Similarly, the whole 4430 speaker is also a "negative" speaker - that is, a positive voltage input to the RED (non-black) terminal will result in a NEGATIVE pressure. So be sure its wired correctly. Why the polarity is that way is a long story, best to search in the archives under "polarity" for the discussions. See this tech paper from JBL Pro:

http://www.jblpro.com/tech-library/JBL_TechNoteN1V12C_v5.pdf

Use the schematic below to be sure everything is as it should be - the 4430 should be able to give you very good bass response even in non-soffit mounting, just not as fully extended when mounted in soffits.

http://www.jblproservice.com/pdf/Studio%20Monitor%20Series/4430LR.pdf

Let us know what you find.

Regards,

Bart

[modena]

to you guys, for sharing your experience. I will do my homework, as Bart suggested and i will check polarity.

George

[modena]

to play around, so this is a sum up of my (quite limited) experience with 4430s so far.

Bart, I did a rough check and polarity is correct. But i will do a more extensive check, with your diagram on hand, as soon as i get some spare time. Bass is there, it just does not exceed my expectations, mids are a bit forward, (setting L-pads to -2 or -4 helps)...but trouth is, that these 4430s make listening to music an enjoyable and unique experiece.

Readswift, room acoustics comes next. (I bought a s/h Behringer DEQ2496)
And last, i might try different amps, as i have a Rotel and an Art Audio lying arround, just to compare with my BVaudio. (though i don't expect much)

Until then, the ultimate tweak for me, is good recordings...
Listening to specific CDs (John Mayal "Along for the Ride" 2001 CD comes first in mind) is pure magic... Poor recordings through the 4430s are simply unlistenable.

George

[readswift]

I'd neverf advise digital processing to adress bass related problems :blink:

Neither of my tipps were about digital processing. I'd be aware doing so , clocking issues might arise.

[modena]

Do any of you guys have any experience in soffit mounting the 4430s? Can you point me to plans or "How to" guides to built soffit? Think i could do that, if it would improve performance... but i cannot use cement or bricks... just these Rigips sheets (plasterboard?)

Many thanks
George

[richluvsound]

George,

can you post some details of the room make-up -what are the walls ,floor and ceiling made of ? Dimensions ? Soffit mounting is not worth doing in some cases. The money may well be better put into room treatment/correction ! Perhaps bi-amping will help with the LF / HF balance.

First things first . DIMENSIONS .

Rich

[modena]

Here it is... It's the meeting room of an open space, 270 sqm graphic design studio. 11m of windows with rollers or blinds, 4m of cement wall, granite or laminate floor.
Actual listening space, with sofas etc but no carpet, about 26sqm. (4,4 x 6m)

[richluvsound]

George,

you are going to struggle with both the shape of the room and having an almost continuous glass wall down the right hand side . I can't imagine how much reflection there is in that room. Concrete and glass :o:

Try this :

get the 4430 off the floor min 600 mm and couple them to the floor on sand filled steel stands , bring them forward to just in front of the stairwell. Get a rug to place in front of the cabs. . Think about changing the room around and keep in mind the Golden Section, 1-1.63 this the ratio that most studios are designed to . You are going to have to reduce the room reflections to have anything like a decent sound .

I would swap the room around and put absorbtion in front of the glass where its needed ,but thats just my opinion. Andy Oz would be your best bet . Send him a pm and ask for advice !


Rich

[Andyoz]

I'm confused, where are the speakers in relation to the listening position?

Surely they are not 11m away....if so your, direct to reflected sound ratio would be slightly "strange".:blink:

I think soffit mounting is the least of your worries at the moment.

[grumpy]

listening in a working environment? I'd personally consider hanging them...
upside down & angled down a bit. Out of the way & not primary focus. Still
can sound very good. -grumpy

[modena]

Andy, sorry if i didn't make it clear. Listening position is quite flexible, as i can move sofa forth and back, but no wall behind it. Yes, windows are a problem... thinking of installing fabric rollers(?) (like curtains, but flat, no folds) U think these might help?

Rich, afraid cannot move them that forward, there will be a bar next to that wall (BTW, solved the Mac issue?)

Grumpy, these won't be used for background music during working hours, but for serious listening after work, as there are no neighbours around. Hanging them... suppose i could do that, as no works in the space have not been started yet.

George

[Krunchy]

Think about changing the room around and keep in mind the Golden Section, 1-1.63 this the ratio that most studios are designed to .

Hi Rich !
Can you elaborate on this as it pertains to this discussion and speaker placement. very interesting! :)

[Robh3606]

With all that glass I would set-up for a tight listening space within the room. Set up your speakers for a 8' spacing and sit 8' out so you have an equilateral triangle. Toe them in so you are on axis with the horn throats. This will delay the reflection off the windows. The 8' spacing is just an example. You use what's best and workout what distance from the wall/speakers gives you the smoothest bass response. Even though they are 100x100 you can still use the horn directivity to your advantage. Those are short throw horns so don't be afraid of getting in close.

Rob:)

[Andyoz]

Yep, best you can do is get the direct to reflected ratio up by getting in close.

[sourceoneaudio]

Modena,
Have you tried moving them fully into the corners? This will help much on LF output for every boundary you gain 3db of LF boost. Also I would suggest a very large nice/thick area rug in front. Also in a two channel listening situation a perfect triangle is recommended. This of course is up to you and the room set up if even possible. ??

;)