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Need advice for renew JBL L300

Hi all,

I have L300 speakers which I really love,
But due the age I think i can get much better sound if I renew some of the parts,
Starting the LPADs which currently they are quite noisy .
Far as understand I need 16ohm and 8ohm but not sure what to buy.
I found these ones:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-254

and for the 8 OHM:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-252

In addition i'd like to renew the croosover but need advice where to start?I'd like to focus on the critical parts that is recommeneded to replace and just rebuilding the crossover.

Thanks you all!
avico
avico OP
18 posts
 
The LPADS are really hard to move,and making lot of noise .
Can you please explain how to clean them?
In case they are total lost(almost sure one of them broken).
Can you please which LPADs can I use instead?

reagarding te caps , some one explain me that all caps have expiration date and speakers that are 35 yrs are must renew with new caps is it true?
any recommenedation is most welcome.
magfan
1,583 posts
 
Caps apparently don't age well.
Oil filled? Bees Wax(!) and others can dry over long time periods.
Newer cap designs may pay dividends with better sound. Crossovers are a thing unto themselves. Some guru might even recommend dropping the iron core inductor, if so fitted, and go to air core.

You might want to replace the L-pads altogether with a fixed resistor after getting everything sounding right. Measure carefully!
Some speakers had (have?) a switch for 2 or 3 settings, with different resistor values to be switched into or out of the circuit as needed.
avico OP
18 posts
 
Thanks Magfan

I'm not sure I want to bypass the lpads cause I think they can be useful especially when I'm moving(living in a rent house) and the acoustics is different.
In addition,I'd like to keep the original design .

Is some1 know for sure what LPADS will fit?I'm asking it again cause it's diffcult to replace them because it's require removing the original aluminium tabs and these are attached to front cabin(the lpad's knob placing right behind it).
tried to remove but the tabs bend easily.
btw-Any ideas how removing this tab without bending it?
magfan
1,583 posts
 
That there are few if any modern speakers made with L-pad attenuators should say lots about 'em.

My panels have jumpers where fixed resistors can be installed. You could do similar and have a place to jumper in resistors to lower the HF output. Though why would you? Setup makes a huge difference.
magfan
1,583 posts
 

lpad link::

http://www.bcae1.com/lpad.htm
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