L50 troubles

[Laslo]

Hi there, I was recently given of a pair of JBL L50's however ive been having some troubles with them. One of woofers has busted so i don't expect to get much sound out of it until i fix it or have it fixed, the other appears to be in perfect condition but gives very little sound. I've tested it on two recievers, a Yamaha RX-350 and a Yamaha A-960, both of which give the same results. When the volume is on full on either reciever, the non-busted woofer vibrates alot as if it were playing at extreme levels.

Both woofers are 127A's

I've been contemplating either replacing both woofers with either 127A's or 125A's, however there could be a problem with the crossover. If not that, I might just pay to have them fixed.

If you have any ideas on what may be wrong with these two or any advice on how to remedy the situation, that would be greatly appreciated.

Cheers, Sam.

[pelly3s]

pull the bad woofer and measure the DCR, then put some audio through it and move around the tinsel leads at least that will help you figure out if it needs a recone or not

[boputnam]

One of woofers has busted

Explain "busted". You likely need some new surrounds...

[Laslo]

Sorry about this but i'm very new to DIY speaker repair so I understood very little of what you had to say pelly3s

I also forgot to mention that I took the good woofer out and ran some audio straight from an amp to its connectors. While sound was coming out, it was at a pretty low level. Also, I believe it is the surrounds that have gone on the other one. I did the same thing and connected it straight to an amp and sound came out so thats a plus.

Do you think these speakers are worth having both woofers fixed or replaced? or will the advantage over my current TLX-12's be minimal?

I can always wait a little while to get them fixed, i've just turned 18 so my funds are pretty minimal right now

Thanks for the replies.

[boputnam]

Do you think these speakers are worth having both woofers fixed or replaced? or will the advantage over my current TLX-12's be minimal?

Dunno... That depends.

Can you post some pictures of the woofers? Your idea of running the woofers on the bench, while interesting, unfortunately does not tell very much. On speakers of this vintage, it is likely the surrounds are toast - unless they have been misused in some other manner.

I bought and refurbished a pair for my 18-yr old daughter, and I can tell you these really can sound excellent. They got the "pump", dood.

Refurbishing does not cost a great deal - believe it or not. It will require some time and interest on your part, but the results are usually very pleasing.

[johnaec]

I also forgot to mention that I took the good woofer out and ran some audio straight from an amp to its connectors. While sound was coming out, it was at a pretty low level.

You'll get almost no volume at low frequencies when the speaker isn't in a cabinet because the back wave from the rear almost completely cancels the front wave. What does it sound like in a cabinet? (With the other drivers also mounted - the only output you want from the back of the speaker is what comes out the port.)

John

[Zilch]

I would advise not playing these until they are repaired. If the surrounds are shot, you could be damaging the voice coils doing this....

[Laslo]

Dunno... That depends.

Can you post some pictures of the woofers? Your idea of running the woofers on the bench, while interesting, unfortunately does not tell very much. On speakers of this vintage, it is likely the surrounds are toast - unless they have been misused in some other manner.

I bought and refurbished a pair for my 18-yr old daughter, and I can tell you these really can sound excellent. They got the "pump", dood.

Refurbishing does not cost a great deal - believe it or not. It will require some time and interest on your part, but the results are usually very pleasing.

I'll take some photos tomorrow morning for you, then I might be taking them to get quoted for repairs. Thats good to hear nonetheless about the quality of them and i shall keep you posted

You'll get almost no volume at low frequencies when the speaker isn't in a cabinet because the back wave from the rear almost completely cancels the front wave. What does it sound like in a cabinet? (With the other drivers also mounted - the only output you want from the back of the speaker is what comes out the port.)

John

The low volumes came while the woofer was secured into the cabinet, interestingly enough, when i switched the woofer over to the other cabinet which originally housed the blown woofer and i noticed a slight increase in output.

Thanks for your help guys, ill post photos tomorrow and may have them checked out.

[Laslo]

Ok, i've taken them to get fixed and I should have them in around a week

Thanks for all your help, i'll post pictures of them fixed and my report of how they're running when i get them back

Sam.

[Laslo]

I got them back yesterday and they're running really well

The place i got them fixed always does a great job, so if you''re in melbourne and need a set repaired, have a look at Total Recoil

I've taken 3 speakers there and they've done great jobs. On these L50's, they were nice enough balanced them precisely. They drilled it into me that i'm not to play around with the levels on the front because it took them so much time :P

Anyway, here are some photos of how i'm using them, I decided to put my TLX-12's on top of them so that their tweeter was close to earlevel when sitting. Keep in mind this is my bedroom setup.

[pelly3s]

what are the woofers and tweets in those L50's

[pelly3s]

about the balancing of the L-pads that they did, all that work they said they did involving that really is useless because it all depends on the room they are in and how they are set up.

[Laslo]

They're kevlar recones of the original drivers. The tweeters are replacements which they manufacture.