I have some L-88s that I have been tweaking for about a year now. I have replaced the original 8uF cap with a new polycap and upgraded the binding posts. I have added more fiberglass to the back. Now I have gone and replaced the old LE25-1 tweeters with some 035Tiís. I must say they sound pretty darn good. Both the old and new are suppose to cross at 3 kHz.
I found a crossover formula datasheet at www.mhsoft.nl and http://ccs.exl.info/calc_cr.html#lpad both gave me a whole bunch of different values for one thing. A first order xover shows using a 13.25 mH inductor on the Woofer and a 13.25 cap on the tweeter. Does the fact that there is an inductor here change the value required for the cap?
I have also looked at some of the crossovers that JBL uses for the L1 and L20T both of which are 2 ways with different woofers instead of my 123a.
Question is, should I make a new xover? Right now the modeling program shows a x over point of5000 with an 8uF cap. Below are the T/s specs I have found on drivers.
Re 4 8
Fs ave 1900 25
Z max ave 15 ?
F1 ave 1500 ?
Qms @3 5.3
Qes @1.5 .54
Qts @ 1 .49
Somewhere on this forum someone published the specs for the Le25 and the 035Ti and 035TiA . Above are an average for the measurements he found. The 123a are the specs from unibox. I wrote down the specs for the 035 and now I canít find the thread to write out the specs on the Le25. Iíve looked at many threads here on the L88, 035 L100 etc. and I am very confused. It seems that plugging the port is the way to go but in my situation it may not be. My main listening room is 13í wide x 15í The speakers are on the bookshelf (appropriate enough) about 40Ē off the floor to clear some heavily padded furniture and thatís the only place they fit. They are about a foot from a very short wall. Both sides open up with large archways to other rooms. A 6ft archway on the left to a 10x10 room and on the right a 9í archway into a room 14x15 so I get almost no gain from the walls. The 035s have opened up the sound stage. Being better at dispersion than the old cone tweeters and not as beamy. I must say I like them very much the way they are but I always say if it isnít broke tweak it.
I see lots of options but none of the thread Iíve read on this and other forums seem to match. Do I copy a later JBL crossover even if it isnít a 123a woofer? Anything close? Do I use a 1st order xover with an inductor? Change the cap only?