Bypassing for Solen MKP in crossover?

[lucpes]

I just swapped the NPEs in my speakers (Infinity RSII) for Solen MKP types and despite the fact that the level of detail is largely increased they sound very harsh and screechy. Maybe a bypass is in order? but with what?

[li_gangyi]

maybe you would like to wait for a few days...for the caps to settle and burn in...and then decide on bypassing them...

[lucpes]

Ok, still harsh (essing) after a couple of days

Marantz CD-94 to passive attenuator (short cables) to Slone OPTI-MOS 200W kits to Infinity RS II so I don't think the harshness lies somewhere else in the chain.

[docjoe]

hi
was the sound harsh before changing caps?
did you check the mesured values of the caps you removed and put solen at the exact value
some times caps have different value than that read on the cap!

are you sure that the correct impedance is respected with your passive attenuator beetween the preamp and amp?
some times it is better to use a buffer after a trimmer for impedence matching;

the CD 94 has remote volume, did you try without the passive attenuator? that is cd to amp direct via the variable cd output?

anyway IMO bypassing caps in a speaker is not necessary as the caps values are low (1 to 20 microF?)
adding parallel caps increases the total value and changes the crossover behaviour:
bypassing is for high value caps (10.000uF) you add 5uF and .47uF in parallel it will not change the overal capacity (10.000+5+0.47=10.005.47)

[Jay]

Originally posted by lucpes
I just swapped the NPEs in my speakers (Infinity RSII) for Solen MKP types and despite the fact that the level of detail is largely increased they sound very harsh and screechy. Maybe a bypass is in order? but with what?

I don't know this NPEs, but I think it is similar to elyt caps used in many UK's loudspeakers. And I know that the harshness and screechy things are real. But that's audio, we almost always encounter trade-offs.

IMO, smaller value tends to bring details. May be it is the objective from the first place. Every type, every brand of caps, as well as cables, have their own signature. And it is like cooking, you should know how to use salt along with other ingredients.

In term of distortion introduced, Solen MKP is not that good compared to most caps I have been using, but to the NPE it should be an upgrade. Try "bypassing" with 1uF WIMA MKP10

Originally posted by docjoe
Anyway IMO bypassing caps in a speaker is not necessary as the caps values are low (1 to 20 microF?)
adding parallel caps increases the total value and changes the crossover behaviour:
bypassing is for high value caps (10.000uF) you add 5uF and .47uF in parallel it will not change the overal capacity (10.000+5+0.47=10.005.47)

The bypassing cap should be part of the designed capacitance. And it should not be big-versus-small like in ripple rejection. I use different caps to take the best out of both worlds. Or to use a good expensive cap in any crossover I come up with (in parallel with Solen).

[lucpes]

I measured the caps before installing ant they fall in the same ranges as the ones before (less than 5% tolerances eg. 12uf instead of 12.5uf, shouldn't be a problem). Before the change the sound was somehow blurred, but very musical & sweet (almost tube-like - very nice with female voices) and now it's cold, harsh and somehow upleasant (though guitars, bass, percussion & ambient sounds much better).

I only changed the capacitors in the midrange section (two 75uf paralleled for the 150uf + the rest - 2x12uf, 1x6.8uf ) as the high section already had a quality pp cap and the bass is hopeless (to change - anechoic response is 36Hz -2dB) with these values:

[Jay]

Originally posted by lucpes
(less than 5% tolerances eg. 12uf instead of 12.5uf, shouldn't be a problem).

That's a critical position. It could be a problem.

[KevinLee]

Hello,

Just my 2 cents worth.

I would suggest at least 80 or 100 hours of play time before the Solen caps are broken in.

Try a different type of cable between crossover and tweeter, perhaps a big old stranded piece of 12 AWG.

If that does not help, may I suggest an aluminum foil/paper in oil cap of the smallest value you can find.

Good luck

Kevin Lee

[stappvargen]

Or maybe the tweeter just plain sounds bad!
Now you are hearing it for the first time...

[chris ma]

IMHO

Sounds like there is not enough copper and too much silver.

Chris