Improving a pair of 4301B

[tweeter]

Hello guys.
This is my first post.
Recently I´ve purchased a pair of beautiful 4301B monitors.
The cabinets are in near mint condition but woofers needs a new foam surrounding.
How can I test the electrical health of drivers and filters?
What can I do to improve the performance of the speakers and restoring the cabinets?
Thanks for help and suggestions.

[soundboy]

Plug them in and run some music at low levels....and listen to the drivers. I, too, have a mint pair of these. I replaced the old mylar caps with SA series Claritycaps, bypassed with .01 Auricaps. Let them break in and smooth out for a few days....and spray contact cleaner in to the L pad for the tweeter...And that's it. If you just replace the surrounds, and use Auricap .01 bypasses on the origonal caps, that is an easier, quicker, cheaper, very noticeable improvement. I wouldn't mess with the design, drivers, or crossover values. It's a killer little speaker....better than the sum of the parts used. The tweeter is quite surprising with better capacitors. Search out Rick Cobb on this forum for the surrounds...I used him, and everything worked perfect, without removing and messing up the dust cap....My two cents.

[SEAWOLF97]

others may disagree , but when I am testing unknown speakers that need LF refoaming....I lay them on their backs , facing striaght up so that gravity is not working against their lack of centering support. not very loud, tho.

[soundboy]

others may disagree , but when I am testing unknown speakers that need LF refoaming....I lay them on their backs , facing striaght up so that gravity is not working against their lack of centering support. not very loud, tho.

Yes, that's a good idea.

[tweeter]

Thanks for suggestions.
About cabinets, I´m going to re-paint, so I wonder which color is the front blue paint.
Any help?

Thanks.

[soundboy]

Thanks for suggestions.
About cabinets, I´m going to re-paint, so I wonder which color is the front blue paint.
Any help?

Thanks.

Someone on this forum has the correct paint color...it's a tough one to duplicate. Don't know about where you are, but my local paint store has a scanner that can duplicate anything within a fraction of a percent. Tried it once, and was amazed. Always wanted to try JBL blue....but they said I would have to hold the speaker myself in front of the scanner. 4301's....easy...4331's, well:blink:

[hjames]

Thanks for suggestions.
About cabinets, I´m going to re-paint, so I wonder which color is the front blue paint.
Any help?

Thanks.

You might try the Search function for JBL paint - I know I ran across them talking about it and they even had paint color names from one brand ... It may have been Bo Putnam so an extended search for JBL Blue and username boputnam may get you what you want -

AH - here 'tis! (try #26 in this thread)

http://audioheritage.org/vbulletin/showthread.php?t=1910&highlight=JBL+Blue

[tweeter]

Thanks guys!
I can see that RAL 5005 or 5007 would match with original Blue color.
I´ll try to find it here in Spain.

About crossover network, I´m in doubt the kind of caps to bypassing the original Mylar caps.
Which are better, polypropylene or polystyrene?
What are exactly the caps I should have to purchase?
Audiocaps?
Auricaps?

Sorry for my ignorance.

[Zilch]

AudioCap Theta, 0.01 uF

[soundboy]

Auricap 600v .01uf

[tweeter]

¿?:blink:

[Joe Alesi]

Thanks guys!
About crossover network, I´m in doubt the kind of caps to bypassing the original Mylar caps.
Which are better, polypropylene or polystyrene?
What are exactly the caps I should have to purchase?

Hello Tweeter:

If it's a 0.01uF just use a 400 V or 630 V, Polystyrene (i.e:film/foil construction)

Best
JA

[Zilch]

¿?:blink:


:p

[Joe Alesi]

Plug them in and run some music at low levels....and listen to the drivers. I, too, have a mint pair of these. ...........
...........
It's a killer little speaker....better than the sum of the parts used.

Hello Soundboy,

Since you have these, perhaps you could comment on whether you feel they could do with any more bracing as that might be a modification that "Tweeter" could also easily do. How do they withstand the usual knuckle tap test? Of course being a smaller cabinet makes them better in terms of stiffness anyway, but you never know.

Best
JA

[soundboy]

¿?:blink:

Your point?

[soundboy]

Hello Soundboy,

Since you have these, perhaps you could comment on whether you feel they could do with any more bracing as that might be a modification that "Tweeter" could also easily do. How do they withstand the usual knuckle tap test? Of course being a smaller cabinet makes them better in terms of stiffness anyway, but you never know.

Best
JA
I wouldn't do anything other than crossover parts upgrade, because:

1. They sound great the way they are after cap upgrade.
2. Adding structure to the inside would be a pain, and change box volume and tuning. You are then messing with a great part of this system for it's size....the bass.
3.They don't need it. My pair is solid, without any major resonances, and lot's of fibreglass lining.

[Zilch]

Your point?Tweeter asked which of three capacitor alternatives would be recommended, and got votes for all three. :)

Actually, "Search" will reveal more comprehensive crossover upgrades for due consideration, I beleive.... :yes:

[soundboy]

Ok. :D

[tweeter]

Well, I understand more or less.
I suppose I´ll use polypropilene Aircaps, Ok?

Finally, I found RAL5007 color at last!, what a lucky!
so, my last question about Blue color is the correct finishing,
Brilliant, Glossy or Matt?. That´s all.

Thanks in advance.

[soundboy]

All of the 43XX JBL's I have had are more of a satin finish blue....although I have only had two......the 4315, 4301B.

[tweeter]

Has anyone upgraded the internal wiring and modified crossover network to biwiring.
Will get any improvement?

Regards.

[soundboy]

Has anyone upgraded the internal wiring and modified crossover network to biwiring.
Will get any improvement?

Regards.

Upgrading the internal wiring may make them sound different...but not a huge improvement like better, more modern capacitors. Frankly, I am as big a tweek as there is, and I think it a waste of energy and time, considering the small wattage they will be see, and relatively short wire runs. It seems, with the huge amount of money JBL put in to the bigger monitors (state of the art caps, metal network housings,foilcals on the baffles, and on every driver, etc) if it made any difference, they would have used bigger internal wire.
As for bi wiring, it may help if you are also bi amping...in a three way system, with the woofer seperate from the midrange...in a two way, crossed at 2500 hertz, it seems another waste of time.