L100T crossover Capacitor Upgrade

[rek50]

I Think you have a workable plan. Yes, combine caps in parallel to hit the ORIGINAL values. Replace ALL caps (C-1 40uF, C-3 17uF, C-5 14uF, C-7 3uF) with Dayton Metallized Polypropylene Capacitors. Replace C-2, C-4, C-6, C-8 .01uF with AUDIOCAP PPT THETA .010uF-600V FILM/FOIL CAPACITOR.

http://manuals.harman.com/JBL/HOM/Te...L100t%20ts.pdf

[L100t Owner]

I Think you have a workable plan. Yes, combine caps in parallel to hit the ORIGINAL values. Replace ALL caps (C-1 40uF, C-3 17uF, C-5 14uF, C-7 3uF) with Dayton Metallized Polypropylene Capacitors. Replace C-2, C-4, C-6, C-8 .01uF with AUDIOCAP PPT THETA .010uF-600V FILM/FOIL CAPACITOR.

http://manuals.harman.com/JBL/HOM/Te...L100t%20ts.pdf

I don't hav eany experience with bypass caps. C4 and C8 were originally 0.1 uF bypass caps. Why the lower value? (to 0.01 uF).

Chris

[rek50]

I see on the schematic that they were listed as .1uf. It could be a typo (error) or an earlier thought/design. If you look at the later (Rev D) network,

http://manuals.harman.com/JBL/HOM/Te...100t3%20ts.pdf

the bypass caps are all .01uF. Also note the change in the network, using the SAME drivers (speakers-LF, MF, HF). The network was revised for better sound/performance.

[L100t Owner]

I see on the schematic that they were listed as .1uf. It could be a typo (error) or an earlier thought/design. If you look at the later (Rev D) network,

http://manuals.harman.com/JBL/HOM/Te...100t3%20ts.pdf

the bypass caps are all .01uF. Also note the change in the network, using the SAME drivers (speakers-LF, MF, HF). The network was revised for better sound/performance.

I am really glad I asked the question. Thanks, I will order all 0.01 uF's. Now I see where you got the price of $3.47 each.

Chris

EDIT: I just pulled the crossovers, yep, they are all 0.01 uF's. I didn't pull them before because the midrange wires had hot melt holding them to the inner enclosures. Glad I asked about the two sizes. Going to place teh order now.

[Gioxtream]

What is The best capacitor to upgrade The JBL's? I have tested a few Polypropylene caps.And.. to my Ears the originals (Electrolitics sound way better.) Maybe Because of the speaker design? Go figure!

I replaced the Electrolitics on the board with Polypropylene Erse Xpulse caps and the lack of transparency was so obvious.

CaN Anyone Guide me in the right direction? Thanks.

I just went down this same road with a set of JBL 4425s. I ended up using Dayton caps along with .01mf bypass caps on each large cap - the original way that JBL did it. Do a search on my name and you'll see the discussion here.

I've used Solens in the past with good success on a set of UREI 809s, as well. All nice caps. There are as many opinions on the boutique-ness of caps by brand name, so I'll not go there. Suffice it to say, though, that I've observed the same effect on both speaker systems with different brands of caps: The high frequency output went up so that I had to readjust the output levels. Also, the quality of the amplification you are using will have an effect on what/how you hear the changes.

Just my experiences.....

Cheers,

David

[bandolino]

What is The best capacitor to upgrade The JBL's? I have tested a few Polypropylene caps.And.. to my Ears the originals (Electrolitics sound way better.) Maybe Because of the speaker design? Go figure!

I replaced the Electrolitics on the board with Polypropylene Erse Xpulse caps and the lack of transparency was so obvious.

CaN Anyone Guide me in the right direction? Thanks.

I am not the best person to answer this, since I have limited experience, but since no one else has responded yet, I'll post.

From what I understand, when the crossover is upgraded with new capacitors (and/or other components), it can take many hours of play time to "burn in" the new capacitors. Opinions and experience differ on exactly how long the burn in time is, but I have read variations from about 10 hours to 4 weeks. During the burn in process, the sound can be quite different from how it will sound later. This is a possible explanation for your experience, if you didn't yet burn in the new capacitors.

If you still experience this after the capacitors have had plenty of burn in time, then perhaps it is just personal preference. Different people respond differently to any number of elements in an audio system. Some people say that they greatly prefer the sound of electrolytic capacitors to polypropylene capacitors, especially in vintage speakers.

Good luck with your projects, and enjoy the music.