Bypass capacitors in crossovers

[glynnw]

Tony Gee's site ( http://www.humblehomemadehifi.com/ )  recommends bypassing each capacitor in a crossover with a Vishay .01 uF cap, saying that the improvment is well worth the low price of the part.  I am thinking of trying this with some of the Russian caps on ebay (the Vishays he mentions are not readily available in small quantities  in the US).  Anyone have any experience or thoughts about this? Am I just throwing money away?

[corndog71]

Danny Richie is an award winning designer of premium loudspeakers and he uses bypasses in his designs.

I haven't experimented enough with them to be sure but replacing stock crossover parts with tighter tolerance parts makes a huge difference in the sound.  I like Erse, Sonicap, V-Cap, and in a pinch Solens will do.  Not a fan of Jantzen caps but I like their inductors.  Auricaps are popular but I've never used them.  I like Kimber Kaps too but now they're discontinued.  Mills resistors are excellent too.  Any part in the signal path should have the best parts you can afford.

I've upgraded crossovers for several speakers and all have sounded better for it.

[Grainger49]

Bypassing in crossovers is a time honored tradition.  A ballpark estimate of what value to use is 1/100 to 1/10 of the nameplate value of the existing capacitor.  Since most capacitors are +/- 10% the combination will be within the intended tolerance of the designer.

What to use is anyone's guess.  Although it is recognized that you should use a better capacitor than the existing capacitor.  So if there is an electrolytic, any film capacitor will sound better.  There are Metalized Film, Polyester Film, PETP Film Polystyrene Film, Polypropylene Film and Teflon (PTFE) Film capacitors.  And probably quite a few I missed.  I tried to put them in the order of better sound but I probably screwed that up too!  I should also add that the USSR Military Surplus capacitors (some of us refer to them as KKs), including some POI capacitors they sell, are among the better and cheaper ones out there.  

Although I have no experience with bypassing crossover capacitors I have done this in audio gear and have always been happy with the outcome.  No, I have been happy enough with putting my first KK Teflon capacitors that I have bought large batches of Teflon 0.1uF@200V KP-2 KKs and put them everywhere in my system.  I have purchased KKs in specific values for equipment I intend to buy.  And a few values just in case I can find a good place to put them.

Ok, it is an illness, but you can buy a small batch for the price of 2 of the "designer" caps and have some fun with them.  

Teflon capacitors need a longer than average breakin period.  Here is my post on a relative painless method, you don't have to listen to them when they are not at their best, to break in capacitors:

Fast Breakin Post

I hope this is somewhat helpful.

[glynnw]

To follow-up, in my Straight 8s I have already upgraded all parts to Auricaps, Mills resistors and Alpha-Core coils.  I also have a pair of Basszilla speakers using cheaper parts -Solens, wire-wound inductors, etc.  I guess my best bet is to simply order some of the Russian caps and play with them.  Any more input is appreciated - I won't order until next week.  Any ideas on what types of his smaller caps might be best on Auricaps and Solens?

[2wo]

As you can use the lower voltage ones, I would try some of the Russian Teflons.

You can also look at the K40 PIO, probably a bit warmer...John

[corndog71]

don't forget proper placement of inductors to maintain the proper values and reduce crosstalk.

http://www.troelsgravesen.dk/coils.htm

[Grainger49]

don't forget proper placement of inductors to maintain the proper values and reduce crosstalk.

http://www.troelsgravesen.dk/coils.htm

Interesting...  Great link.

I helped Paul "Paully" install a Bob Crites crossover in his Chorus II speakers.  The inductors were side by side and about 3/4" apart, if that much.  They were not in series but certainly, from your link, they interact strongly. 

What about iron core chokes?  I asked once about the fields and there was no definitive response.  I don't even remember a response about orientating two chokes on a chassis.