recapping crossovers....do or don't?


I need some advice....I have recapped several pieces of my system with good results. But I am really hesitant to do so with my outboard crossovers on my speakers. The reason is they sound wonderful.....very coherent,musical,and image beautifuly. You ask why look for trouble....well the crossovers use MIT multicaps which I think are fine...but there are about 4 Solens also. Solens have a soso reputation and are not known as a really hi quality cap.

Do you think there is anything to gain here or am I playing with fire....BTW these speakers have Dynaudio drivers and are about 94-96db efficient.
wavetrader
Have you asked MIT? Just because they do not use pricier caps does not mean they might not have a suggestion. It never hurts to ask, and who would better know.
If you wish to experiment, just make sure you remove the originals carefully and hang on to them.

Then, if you don't like the change, remove the new ones, solder the old ones back in place and enjoy the original sound, knowing that your experiment helped remove any doubt you may have had about what to do.

Just remember that sometimes the most expensive part is not the best choice. There may be a reason they chose the parts they did.
I think the point about removing the old caps carefully makes a lot of sense. If I make a change I will replace the Solens first....These crossovers were last modified in 1996....so I think the choice of quality caps has improved greatly....nothing ventured...nothing gained as they say...
My Maggies have 22mfd in series with the tweeter. This is composed of 4 caps from 0.1mfd to 10mfd. Any harm in simply replacing with a single 22mfd unit of the appropriate voltage?

Maggies ALSO use Solens of about 5$ ea.
Is there any middle ground between these and 200$ Mundorfs?

The Clarity cap 'SA' would cost about 130$ for 2x22 and 2x25.
Which MIT caps are they? PPFXS sound better than PPMFX. As an interim step, consider experimenting with small bypass using .1uf or .22uf Russian FT-3 telfon available cheap on ebay. Also, it's worth trying Duelund graphite resistors in key positions-- probably a bigger improvement than a coupling cap upgrade.
Also keep in mind that crosover caps require some time to "burn-in", and may sound terrible initially(not as great an issue, if you just bypass). Generally speaking: The better the cap's dielectric(polystyrene/polypropylene/Teflon), the longer the burn-in. The Duelund resistors are a good suggestion. An excellent place to shop: (http://www.percyaudio.com/Catalog.pdf) Ask Michael to match everything to 1% tolerance for you(He gets way closer than that).
The Duelund resistor change I find interesting.....I think they are halco on there now. There's all kind of options here....these speakers were designed to tweak...the boards come of in minutes. I'll probably go with duelands or VT...since those are considered the best sounding. With the recent rise of the dollar vs Euro...the Duelunds look real good.
Capacitors are a can of worms. Unless they are truly junk change out the inductors first using air cores wherever the original XO used iron cores.
Wavetrader...That's good news. Maybe it means that they knew what they were doing when they picked the capacitors.

If you do make changes, do only one speaker to start with so that you can compare your results with the stock XO.
Compare XO's hmmm....I think that might be easier said than done...I think I'll just do the 2 and go from there. Comparing singles...the breakin might color my thoughts...but who knows.

The idea to use by-pass caps really intigues me....as I could use the Duelunds with the MIT's. I have read that doing this would give me the signature of the Duelund sound....anybody have experience or thoughts about using a small by-pass cap..
Eldartford.....of course the designer knew what he was doing...no really....but that doesn't mean there can't be improvements made. I really am sold on using caps to make overall improvements on my gear....not every piece mind you but the low cost ones just make sense.
See this mention of MIT multi-caps from DIY'ers. Not recommended. Bear in mind this is a precision audio crowd who like Tannoys and SET amps (precision is desired and smooth is shunned - I don't know what side of the fence you are on but it is the same with most audio gear - some appriate the detail and others find it annoying or less musical)
IME MIT/Multicap PPFXS tin foil sound much better than the PPMFX metalized prop caps that rate poorly in Shadorne's URL. PPMFX were widely used by ARC and others circa mid '90s, but have a hard unsupple sound in the presence region and above that you don't want in a coupling or crossover cap. MIT/Multicap RTX styrene caps are still in great favor among many DIYers for bypass applications.
The MIT's I have are PPFXS caps....what do you thimk od using a small Duelund bypass?
Wavetrader...Comparing stock and modified speakers is very easy. You put them side by side, play a mono source, and swing the balance control from side to side.
Eldartford.....I can do that very easily...my vintage Accuphase pre happens to have a nice smooth balance control.
If you do compare the speaker systems as soon as you complete the upgrade: Prepare to be disappointed. That is unless you "burn-in" the caps on a rack before installation.
Wavetrader, before going for expensive Duelund or V-Cap TFT bypass I would first try some cheap russian FT-1 or FT-3 teflon in .01uf & .1uf and decide whether bypass is a net improvement at either of these values. If true, then sub in Duelund or V-Cap in equivalent values. If false, then sub in Duelund or Claritycap MR at full value of stock PPFXS.
Wavetrader, your speakers already have great components. Holco and Multicap PPFXS are top notch. If I were in your shoes, I'd think twice about this project, but if you really want to makes changes (and it sounds like you do), focus on the caps. Don't mess with the resistors. In my experience, cap upgrades in crossovers offer a much more significant change than resistors. Truth be told, I've never heard a difference with resistors in crossovers, but I don't want to start an argument over that. Let's stay focused on caps. Everyone will give you different suggestions. There are lots of good ones to consider, but I agree with Dgarretson's recommendation. Try some Russian teflon FT-1 or FT-3 as bypass. These are excellent sounding and they're cheap. A pair of 0.1 uF FT-3 will set you back $22 shipped. If you want to replace the whole cap, you may have to upgrade to V-caps or Mundorf to hear an improvement, but you're talking about $1000 for a pair of 3.3 uF V-caps or $150 for a pair of 3.3 uF Mundorf S/O. Prices quickly become ridiculous.

That's my two cents.
One caveat with the Russian teflon's as a bypass. In my experience I liked them a lot on the tweeter, but they were too forward on my mid/bass driver. Also, too much of a good thing can be too much. I would suggest using them on the primary in line cap on your tweeter crossover, but not on any other cap. Use something else on the others, like a RelCap RT or a Sonicap Gen II, or else you might get too much of that teflon sound instead of just the clean transparency.

I really can't understand why this happens, but in my experience it does.

Enjoy,
bob
I'm going to get my modded black gate C200 preamp at the end of this week....I have already got a ton of transparency...so i will wait to see what effect this pre has on my system....thanks for all the input...really helpful.
I have built an outboard crossover for my JBL L-300s. The Duelund resistors are magic! If you have resistors in the signal path you NEED to give the Duelund resistors a try. The Mundorf Gold-Silver-Oil caps are also very very good in the signal path.
Mundorf's new resistors are pretty sweet too, and they're cheap! I can't see using Mills again.
To catch up here...I have 400 hours on my BG/Mundorf Accuphase C200. I think it is a perfect match with my VAC 140's along with my modded Monarchy dac. It hard to imagine my system sounding better....but I can't resist replacing the Solens in my crossovers...I would like a little more extension on the highs...but not Hi-fi...natural...I am looking at the Jantzen Silvers or the Z-Superiors. I have read some good reveiws and they look to be a excellant value. I am really pleased with the low and midrange sound...so I will stick with the MIT's for now...Anybody have any thoughts on the Jantzens??
I haven't heard Jantzens, but they get good reviews.
I can't resist replacing the Solens in my crossovers...I would like a little more extension on the highs...
I agree with replacing the Solens, but don't expect more extension. Premium caps, like Mundorf Silver/Oil, should give better bloom and image density along with a more natural and less fatiguing high end. If I were in your shoes, I'd focus on the tweeter caps. Consider Mundorf, Dynamicap, and Sonicap along with Jantzen.