Here I am trying to mod the speaker with better cap. Hope someone can help to share some steps to avoid the mistake.

Here is the KEF cresta 10 crossover



I have change the cap to all Elko Glatt (Mundorf oem). sounds quite good except the bass is restricted. After I put back original 10uF cap (which is Likon) it is ok and sound surprisingly smooth and revealing.

However When I measure the 7uF (old unit), I found the capacitance is 18uF. Normally the old cap the capacitance will drop after time, but why is it the value higher than what is stated. I measure the other unit and found the same high value.

Then I try put in the 10uF (which is measured to be 12uF) and now do the testing.

Some hints for your capacitance measurements, unless your test equipment is at 'K' pricing, otherwise the cheap regular multimeter won't give you the accurate reading.

So my advice is no need to care about the reading, just use it.

This post has been edited by coolkwc: Jan 4 2009, 01:49 PM

I meausred the old unit and new unit of the same capacitance.

I found all matches well (6uF and 10uF) except the 7uF. The 7uF gone to 20uF. So I dont think my meter has got problem.

Anyway, I tried replacing the 7uF with 10uF M-cap (elko oem) and found the treble is blur. The music is no more natural. So I put back the 6.8uF M-cap (Elko )

I am also told to use lower cap to replace the new cap. e.g. 7uf with new 6.8uF cos the new cap the capacitance is always higher. true ?

for the best result is to try
variant types of capacitor likewise : metal-film, polyproprene, oil capacitor

M-cap 10uF ? its very big !
affordable ones you can tryout Solen capacitor.

i recommend obbligatto premium cap i using for my Mordaunt Short really nice warm n thick sounding
i use for my tweeter and mundorf copper foil inductor for mid

This post has been edited by abel: Jan 4 2009, 10:27 PM

but the first question you have to ask yrself ~

1. You merely change the crossover due to aging ? if not
2. Insufficient deep bass ? mid bass ? mid ? high frequency ?
3. What types of sound do you want to achieve in this modification ?

my advise is stick to the original value of capacitor ~ but higher grade of capacitor likewise mentioned polypropylene/silver-oil or etc.

i believe Kef did many research, measurements & countless hour of listening session to built the crossover.
unless you trust yr own ears..

yeah i agree with that is not easy to built ur own because crossover got few type of network
butterworth , linkwitz and etc and from 1st order up to 4th order some are more hehehehe

i also stick with same value for my speaker

This post has been edited by abel: Jan 4 2009, 10:29 PM

Haha chua, I got 2 10uF and 2 8uF taiwan caps, will send it to u along with your parcel 2moro, let u try try If "ngam" your taste, sell it cheap cheap to you These caps' sound are no cheapskate compare to premium one

apa brand i know china famous obbligatto i very recommend this for budget user i tested it can compared with Mundorf Supreme

This post has been edited by abel: Jan 4 2009, 10:41 PM

serious ? really curious to know ~ what type of material is the capacitor made from ?

Obbligato capacitors are premium polypropylene film in a non-magnetic case. Values are laser etched into the surface. Pure copper soldered lead out wires.

Below is tested the old Obbligato not Premium

I refer from this page at first i not believe i buy n try on my speaker is sound warm n thick sound but also wont lack of detail ... now i got use in my tube amp as well .....
http://www.humblehomemadehifi.com/Cap.html

Obbligato aluminium-foil MKP 630VDC – 5% tolerance

Technical Specifications: Chinese built, extra tight winding, no voids and thick-coated aluminium film imported from Germany. Very low inductance. Lead-outs are soldered copper, solid core.

Sound: Analogue is the word that keeps popping-up in my head when trying to describe these capacitors. They have a rich texture and produce and open and smooth image with realistic dynamics and good retrieval of ambient information. They have slightly less depth than a Clarity Cap DTAC but are also very detailed and never get harsh. They seem to have a sort of “detailed warmth” about them. Very nice especially when you look at their price!

Verdict: 10

Obbligato Film Oil MKP 630VDC – 5% tolerance

Technical Specifications: Chinese built, extra tight winding, no voids and thick-coated aluminium film imported from Germany. Very low inductance. Lead-outs are soldered copper, solid core.

Sound: pleasant “analogue” approach to music with a nice clear, smooth presentation and good separation. Left to right imaging and front to back sound stage is realistic but not as open as the dry type Obbligato. Also the overall balance is a little more forward than the Obbligato aluminium foil type, especially fresh out of the box. So give them some time to burn-in.

Verdict: 9,5

Mundorf Supreme Cap MKP 800VDC – 2% tolerance

Technical Specifications: 1. Special induction-free winding technology: Two capacitor windings are interleaved so that their inductances effectively cancel each other out. These two windings are connected in series. This means that it takes two 2µF windings to make a single 1µF M-CAP SUPREME capacitor - the same amount that it would take to produce a full 4µF of capacity using conventional technology! 2.Best available materials: The polypropylene film used for the M-CAP SUPREME has exceptionally low loss characteristics. 3. Sturdy plastic and aluminium cases:This prevents microphone effect feedback, thus protecting important signal details.

Sound: The M-CAP SUPREME delivers a very spatial sound with lots of depth. Good reproduction of the musical nuances. Detail and depth from the high treble right down into the low mid-range. Furthermore, this effect is not only achieved with very expensive high-end components. It delivers a significant enhancement in more price-conscious configurations, making it a very worthwhile upgrade. Clear and transparent sounding cap with a good sound stage. They provide a good improvement in clarity, focus and dynamics compared to standard quality MKP’s. The degree of improvement is comparable to upgrading to high-end cables and interconnects. I must say I was impressed when I first auditioned them. The Mundorf M-Cap Supreme mix very nicely with Clarity Cap SA type capacitors, so blend the two to make your own personal taste.

Verdict: 9



This post has been edited by abel: Jan 4 2009, 10:56 PM

I put that obligatto into my soundstage 1.5.

After that, I find it very interesting.

but now we are talking about speaker crossover. modifying the cap does not mean it will get out of its tune but more to suit my ear.

the designer ear is not my ear.

polypropylene cap & pure copper ? good stuff .. worth a try.
what is the sound characteristic of this capacitor ?

the housing is make by copper although price are not very cheap
i buy 3.3uf 600vdc about RM 70 per pc if compare to Mundorf Supreme i think more than RM 100
malaysia got ppl sell u go to octave they got sell

that expensive now ?
previously i bought my Mundorf silver oil 4.7uf/600Vdc <rm100 , it was like 5 years ago.

5 years ago hhehe now silver oil for 3.3uf is more than RM 250

my fren just recently buy silver/gold/oil new one 0.47uf is RM 600 hehehehe
very huge different compare old Silver Gold good seperation n depth are like long highway

This post has been edited by abel: Jan 4 2009, 11:08 PM

250 each ??? err... i've about 6 mundorf silver oil & gold coupling cap residing in my power amp ~
if i remember correctly the value is 0.22uF/ 0.33uF/ 0.47uF

This post has been edited by bose00: Jan 4 2009, 11:11 PM

rm600 ? as for me i'll rather order Lundahl Interstage Transformer as coupling and take away those Mundorf coupling cap.

yeah my fren put for his car speaker but his speaker cost few thousand soo ok loh rich man
some more got V-CAP

This post has been edited by abel: Jan 4 2009, 11:16 PM

not to mention i've V-Cap inside my DAC. the V-Cap does deliver the clarity and detail.
but seriously the price you mention is sky rocket high compared to what i have purchased previously.. if its true then i don't feels its
worth investing in these audiophiles cap.

This post has been edited by bose00: Jan 4 2009, 11:30 PM