hello all this is my firtst post ,i have a pair of jm labs 915's that were abused and i want to recap them . to the revised 915.1 i think it was for better bass. i have the schematic .maybe i can post it but i think it for the 915. focal uk was helpful to supply me with this. so what i am looking for it suggestion on new caps and such. i see the mundorf is very favored so i am willing to use them. i have attached the crossover schematic file for all to look at.
thanks any help will be grateful.
thanks any help will be grateful.
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Hey there! Those always kind of captured my imagination as mini-Utopias. The 100uF cap is your best bet for the bass, but your chances of making it better are 50/50. I suggest a Mundorf electrolytic, or a combination of Axons. The biggest issue I have with Focals is they rely on inexpensive SCR/Solens for the films. I suggest if you can, try replacing the 3.9 and 6.8 with Mundorf MKP caps. You'll definitely hear a change, and you'll learn something inexpensively. Unlike the Profiles, this looks like a more reasonable, straightforward crossover. Not much more I can suggest to you without being able to measure the drivers too. Oh, try replacing the resistors with Mills. 🙂
Best, Erik
Best, Erik
Hi cegtv,
can you spare a photo of the abused speaker/crossover? I advise to not let yourself be misled by believing in brands. Take your time to evaluate the current state of the parts and once proven necessary, perform the changes. I believe in fair prices, so if I needed a 6.8 uF cap, I'd just go get 10x mkt 250V Roederstein equivalent for 16 times less money than a single white mundorf mkp cap. A bit extreme DIY. 🙂
edit: Thanks for the filter schematics. Will add to the collection.
can you spare a photo of the abused speaker/crossover? I advise to not let yourself be misled by believing in brands. Take your time to evaluate the current state of the parts and once proven necessary, perform the changes. I believe in fair prices, so if I needed a 6.8 uF cap, I'd just go get 10x mkt 250V Roederstein equivalent for 16 times less money than a single white mundorf mkp cap. A bit extreme DIY. 🙂
edit: Thanks for the filter schematics. Will add to the collection.
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i guess i should have been more clear it was late.
1) cabinets are not great cosmetics
2 )one speaker always sounded lower than the other so i decided i would do a recap as they were made 1998 or so plus i read there was a revision to the speaker. and lets face it ,we are all always trying to improve our audio systems.
1) cabinets are not great cosmetics
2 )one speaker always sounded lower than the other so i decided i would do a recap as they were made 1998 or so plus i read there was a revision to the speaker. and lets face it ,we are all always trying to improve our audio systems.
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Oooh, check the coils!! Sometimes they break close to the board and you can't see it very easily.
sorry folks due to my adhd i keep leaving things out. i also think they have water damage the bottom is loose. and the driver screws had surface rust on them . i want to replace the internal focal speaker wiring.too.
Hi. I also have a pair or these (unused presently) I always felt that the second mid was not working till quite high volume levels. Is this possibly your problem too ? I have not found an answer for this, hence unused.
The mids are in parallel and working in the same frequency range, filtered by the same passive components, so i don't think that a recap would help in your case.
It's slightly off-topic, but both your speakers act as you described?
If you just "felt" till now, please ensure on it, might be a bad contact or cracked solder joint or so. Even a bad driver might possible.
It's slightly off-topic, but both your speakers act as you described?
If you just "felt" till now, please ensure on it, might be a bad contact or cracked solder joint or so. Even a bad driver might possible.
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The main difference between this and the 915.1 are PP in place of the Wicon electrolytics. Maybe AEON 50/250V?
Its`s more or less a waste to replace the 100u and 15U as these are not in the signal path.
R
Its`s more or less a waste to replace the 100u and 15U as these are not in the signal path.
R
RM - You'd be surprised, I've heard a number of folks say they benefited from replacing those caps.
Maybe not worth $100, but for $5, absolutely worth trying.
Maybe not worth $100, but for $5, absolutely worth trying.
good day i found these on the audio vintage forum it is private . they do not let anyone in .weird any way i found these pics of a 915 crossover upgrade cant read all info on the caps.maybe someone can. thanks a enjoy your day paul i have included a stock pic 915/915.1
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Hi Rm: I think $5 is a worthwhile experiment
Doing the wrong thing can be enlightening, especially when cheap.
Doing the wrong thing can be enlightening, especially when cheap.
Roar, can you explain and show what came out of your project? I just bought pair of 915.1's and I am considering the upgrade.
I have donna upgrade of the Point Source Aria 5 in the past. Now let's take it to the next level. 🙂
I have donna upgrade of the Point Source Aria 5 in the past. Now let's take it to the next level. 🙂

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