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View Full Version : Blown L100 ! Why me ?



bonanzadave
11-13-2005, 11:34 AM
I was warming up before the Aussie Floyd concert with a little Dark Side and the LE5-2 & LE25 on the Rt side left the building. I use a Yamaha M50 and and was wondering what I did wrong or what happened. Have already swapped over the drivers and they are definitely bad. I read posts on this site last night for 3 hours. My next step to get this speaker going will come from within. Thanks. Bonanzadave

Mr. Widget
11-13-2005, 12:12 PM
I was warming up before the Aussie Floyd concert with a little Dark Side and the LE5-2 & LE25 on the Rt side left the building. I use a Yamaha M50 and and was wondering what I did wrong or what happened. Have already swapped over the drivers and they are definitely bad. I read posts on this site last night for 3 hours. My next step to get this speaker going will come from within. Thanks. BonanzadaveI have no idea what a Yamaha M50 is, but I am guessing that it is a low powered amp. You are much more likely to blow mids and tweeters by clipping an under powered system. Typically you will hear the distortion telling you to turn it down! If you don't head that warning, the heat generated in the voicecoils of the mids and tweeters that are attempting to reproduce the almost squarewaves your amp is producing will damage virtually any speaker. Crappy speakers are less susceptible to this damage but they too will be damaged.

Assuming this is the case, after you replace your mid and HF drivers get an amp with 100 to 200 watts and listen more closely to the music... it will warn you in advance of failure.

Widget

Don C
11-13-2005, 12:13 PM
The mids may have failed due to the voice coil coming unglued from the former. I have a few like this. If that's what happened, it is not anybodys fault. The bad news is, the other one will probably be gone soon too. You can tell by looking at the DC resistance through the coil. If it measures OK, but puts out no sound, it's that glue problem. I'd put in something newer, maybe a 104H-2. I don't know what to say about the tweeter, except that I have a few bad ones of those too. It's more likely to find the voice coil is open on those.

Mr. Widget
11-13-2005, 12:13 PM
I didn't read this over, but I'd assume it says basicly the same thing I did but in more detail.

http://www.jblpro.com/pub/technote/lowpower.pdf


Widget

speakerdave
11-13-2005, 12:23 PM
I'm with Mr. Wizard, here. Since the mid on that speaker is run full on top, it will also be getting the massive quantity of high frequency grung that is produced by clipping your amp, and you have knocked out the tweeter and mid together.

The good news is that the LE5-2 midrange and the LE25 tweeter are frequently available on ebay (for widely varying prices). I would also check the capacitors in the crossovers, would probably replace them with ones having higher voltage ratings, for the kind of treatment you are giving them--which is OK--I understand completely the occasional urge to feel the sound as well as hear it.

David

bonanzadave
11-13-2005, 12:32 PM
Thanks gents, All I can say is bummer ! I thought the Yamaha M-50 & C-50 were ok. I found a local LE26. Think that will work ? I could scavenge my brothers L166s. Repair or replace ?

duaneage
11-13-2005, 01:03 PM
The M-50 is a decent amp.. Those speakers were pretty old and it was probably just their time. I just sold a pair of 5-2 speakers on the 'Bay and your price to replace them will vary.

I have a pair of 104-H mids if your interested, PM me.

Mr. Widget
11-13-2005, 01:10 PM
The M-50 is a decent amp.. I wasn't suggesting that it is a bad amp... just that it might not have the power to play as loudly as was required. How many watts is it?
Those speakers were pretty old and it was probably just their time.Just their time for a tweeter and a mid to fail simultaneously???

My L100s are pretty old too... I don't expect them to fail anytime soon.


Widget

bonanzadave
11-13-2005, 01:34 PM
Sorry I dont have The M50 specs on hand. The data tag says 200 watts. I understand totally that this is a mid range consumer amp and I got what I paid for. No offense taken. All this infomation is completly constructive. Thanks.

johnaec
11-13-2005, 03:13 PM
Are you sure it's not the crossover? Have you tried the "bad" speakers in the good enclosure, or measured the resistance across the leads to see if the coils are open?

John

morbo!
11-13-2005, 03:51 PM
get your multi meter check your cables too
i would start with the source.
and work my way through the system till i find the weak link
the process of elimination
ive seen people dismantle their entire systems for something simple

multimeter is invaluable

Don C
11-13-2005, 04:25 PM
The Yamaha M-50 power amplifier is rated at 120 watts per channel. I would think that this is enough to avoid clipping unless you listen at very high levels.

bonanzadave
11-13-2005, 07:54 PM
I put the bad drivers in the good box. No joy. I put the good drivers in the bad box. Works fine. I have been known to get the M50 wound a bit. Damn Dire Straits ! Can I use a LE26

morbo!
11-13-2005, 08:01 PM
time to remove the glue from the cone

some carefull prodding with a multi meter might reviel the break usuall near the solder on the -negitive terminal i think inside the driver
and if your real lucky remove the glue and resolder
bingo
make sure to solder well if you find it plenty of heat
them voice coils suck the heat out
but not to hot
lol
p.s attach the multi to one terminal the feel for the wire with a needle while testing the needle with the other probe

bonanzadave
11-13-2005, 08:55 PM
How about a pair of LE26s and 104-Hs. Will this work. Dont want to mod the cabs or work the crossovers.

speakerdave
11-13-2005, 09:04 PM
Well, OK. Applying an appropriate standard to the circumstances and situation as described just about anything might work. Drop 'em in and crank 'er up!

morbo!
11-13-2005, 09:33 PM
where abouts are you bonanza perhapps
someone here can look ay them for you
and probally anywhere in the world

bonanzadave
11-13-2005, 09:45 PM
Morbo, Im in MN. I found a local shop with a LE26 so I might skip work and visit the "Speaker Clinic" in Minneapolis. This all started with Aussie Floyd. These guys rock !! Have you herd them ?

speakerdave
11-14-2005, 07:47 PM
bonanzadave sent me this in a PM, but said it was OK if I brought it back to the thread:

"The LE25-4s on ebay call out 4.2 ohms each. Think these will be ok in the L100s ? Thanks, Dave"

Pesonally, I don't know, but you may be able to get information about the LE25 series by using the search function on this website.

My response to your earlier question about 104's and LE26 really means that you didn't seem to be really focused in on the subtlety of the sound, and so more or less haphazardly chosen components may suit you. Now you seem to be going in the other direction. Best idea is to search out exact acoustical/electrical replacements. There are A FEW differences in model number suffixes that mean only different color, black or chrome, on the frame face, but I am not knowledgable about the tweeter series in question. If you keep looking on the site you may find it. Don't be surprised if no one comes along to save you the work. The people who know some of this stuff feel like they have already repeated it many times and would like seekers of information to use the tools that are available for finding it.

It would be nice if there could be a process of systematically organizing all of the information that is in these thousands of threads, but that does not seem to be possible right now. If I win the lottery I may take out a few weeks and do it myself, but not before.

David

duaneage
11-14-2005, 11:18 PM
The 104H-2 is more damped than the LE 5-2 but in the L100 it should work fine. That is because the L100 had a simple crossover network compared to later models with elaborate compensation . Since the midrange only has an 8 uf capacitor for a crossover network substituting a different midrange will not cause major problems. if it had a 3rd order network with Zoebels and L-pad networks it would matter much more.
The L pad control allows the midrange to be adjusted to match the tweeter, at most you might want it slightly higher or lower.

bonanzadave
11-15-2005, 09:10 AM
Once again, Thanks for the input. Sorry for the newbee drivel. Im exploring the search function with real fascination. Wow ! Im blown away by the expertise and the willingness (by most) to share this vast knowledge. Sorry again for whipping a dead horse but this being the first time Ive explored the guts of these speakers I dont want to do anything wrong. I understand Im kind of a bottom feeder with this system but after about a full days research on this site Ive concluded two things...

1. Go factory equipment when replacing parts. It sounded good then and It keeps the origianlity (value).
2. You get what you pay for. Duh !! (Im cheep)

Thanks again, Ill update when I get them going.

Mr. Widget
11-15-2005, 10:30 AM
...after about a full days research on this site Ive concluded two things...

1. Go factory equipment when replacing parts. It sounded good then and It keeps the origianlity (value).
2. You get what you pay for. Duh !! (Im cheep).

I'd suggest you track down exact replacement parts. They are readily available on eBay and typically reasonably inexpensive. There is room for improvement with the L100 as with any speaker, but unless you know what you are doing, you are more likely to go backwards.

Good luck... keep us posted and when you do get them both running again, use a bit of moderation on the old volume knob. Or, get a bigger amp and possibly bigger speakers too... ;)


Widget

GordonW
11-15-2005, 02:35 PM
How about a pair of LE26s and 104-Hs. Will this work. Dont want to mod the cabs or work the crossovers.

LE26 yes, 104H, no.

LE26 is pretty much (to a degree that it's pretty much impossible to hear a difference) identical to the LE25. In fact, the LE25-2 (which has also been used in some L100As, from what I'vs seen) uses the same exact recone kit as the LE26. If you put the pair of LE26s in, you should be just fine.

OTOH, the 104H is different, completely... different cone material, different diameter voice coil, different type dustcap, totally different. Won't work properly with the stock crossover...

Things you should be looking for, that will work, with quite close similarity to your originals: LE5-2, LE5-5, LE5-9, 2105H. Any of those should work satisfactorily as a midrange in a stock L100...

Regards,
Gordon.

bonanzadave
11-15-2005, 03:34 PM
Thanks GordonW. Once I get these L100s going I'd like to get your input on Amps.