Help L100 Crossover rebuild/upgrade

[markdam]

ok after searching and searching here there are many ways to go. My question to the gurus is if i just redo the crossovers with new caps and Lpads ... would there be any benifit from bypass caps? the two most popular upgrades seem to be the Jantzen and swerd's . anyone have an opinion on these and the loss of the Lpads? (detracting from the originality)
I off course want the one that makes my L100ds sound amazing..... lol

[TnTn]

This is just an opinion since I have not done bypassing on my 4311, I don't think it's going to help since the LE25 does not go that high (from what I read). I think it's good enough to just replace the caps with newer quality caps. I have no opinions on the other mods though but they do seem to be well thought out.

[Swerd]

markdam

If you want something that improves the sound over the original L100, redoing the original crossover, with or without bypass caps, will not do it. You really need to smooth out the midrange driver's response, and in particular, filter out the high frequency noise from the midrange.

Because someone else also recently asked about this, I checked the prices of the parts in my crossover. As of January 2009 the price is $154/pair for all MPP caps, and $121/pair if you replace the two largest caps with NPE caps.

I sent a response to your PM about this with more info about the variable L-pads.

[markdam]

was just pricing/ordering from your partslist. you ordered from both partsexpress and madisound correct?

[Swerd]

was just pricing/ordering from your partslist. you ordered from both partsexpress and madisound correct?
Yes, I ordered inductor coils from Madisound because they had better prices than Parts Express, and I ordered Dayton MPP caps from PE for the same reason. I prefer PE's resistors only because they have their resistance values printed on them. That is much easier than remembering the colored stripe code for Madisound's resistors.

If you use the cheaper non-polar electrolytic (NPE) caps for the two large values in the woofer network, I prefer those from Madisound because they seem to vary less than those from PE. With Dayton NPE caps, roughly 1 in 10 were actually within 10% of spec when I measured a handful, eliminating any savings by using them. This was not the case with the standard Dayton metalized polypropylene (MPP) caps. Everyone I've ever had in my hands has always been very close to the printed value, and these are the standard caps that claim ±10% variance from spec. For that reason, I've never bothered paying extra for their caps that are ±1%.

If you can find parts from other suppliers with similar values (±10%) at a better price, feel free to get them. With inductor coils, be sure to use the specified wire gauge, as changing to a thicker gauge will also lower the DC resistance and alter the performance of the crossover network.

Good luck, and if you have any other questions, just ask.

[markdam]

Cant wait to start the rebuild! I have been listening to my "other brand" that rhymes with
"ipsh" since the L100's went down after a year of solid use.

[leesonic]

Check out my crossover upgrade progess at :

http://www.audioheritage.org/vbulletin/showthread.php?30368-Newbie-JBL-L100-restoration-and-upgrade&p=304955#post304955

[Rusnzha]

Bypass caps are good, charge coupled is better

49765

I am curious to hear some of the other options in this thread.