No problem. You just have to not know which cap is in which box, at which point the Wima FKP will sound just as good as the fancy-brand cap. 😀
I might try it. But I might say, that tubes might like a slightly different cap than solid state.
It is true that the Wima is cheaper by about 1/2, from the SAME sort of product from REL, BUT it is NOT an RT type cap. It is metalized polypropylene, not film-foil polystyrene. I have used both, and prefer RT.
i thought the mkp were metalized and the fkp were film-foil polypropylene.
i wonder how the wima and vishay comparable fkp series compare ...
mlloyd1
i wonder how the wima and vishay comparable fkp series compare ...
mlloyd1
john curl said:
I would say it has to do with the bulk resistivity of the metalized film relative to the foil, and the same for the terminations to the metalization relative to the foil.
Mike.
Traditionally the film and foil construction was preferred where the current was high. It could handle the heat or maybe had a lower esr. In this case the self resonance may be a dominant element. I have seen circuits become unstable when the small bypass was "improved" with a much larger film and foil cap. The self resonance moved into the range where it would interact with the circuit. Sometimes all that is needed is a small bypass cap. A good layout helps. Unfortunately, whats good for audio isn't necessarily good for UHF, and vice versa.
Polystyrene is only made in film and foil. Thats because the metalization process happens at a temperature that Polystyrene can't handle (or so I was told). Soldering leadouts to a film cap is also a special trick since the soldering temperature is higher than the max temperature of the film.
Polystyrene is only made in film and foil. Thats because the metalization process happens at a temperature that Polystyrene can't handle (or so I was told). Soldering leadouts to a film cap is also a special trick since the soldering temperature is higher than the max temperature of the film.
The tin might have something to do with it, rather than aluminum. I have found that the inherent MECHANICAL DAMPING of the cap is really critical.
Here is something I just ran across looking for low phase noise circuitry (low jitter for digital audio) Phase noise in components Yet another way passive linear components are neither.
SY said:
Yes, and the very detailed pictures showing the part brands. I'm pretty sure that a lot of hi-end equipment is layed out with exactly such pictures in mind. Marketing 101.
Jan Didden
john curl said:
AES paper "Forces in cylindrical metallized film capacitors" discussed this. The effect is only measureable with a laser vibrometer at considereable signal levels (like in speaker xover filters) and amounts to a whopping 10-20 pico-meters vibration excursion. A fraction of the molecule diameter.
Jan Didden
Yes, and expensive cars use expensive and attractive paint, but that doesn't make the paint inferior, in fact, it usually is superior to a cheaper paint.
Prejudice against hi end designers runs rampant, here.
Good article, Demian.
Prejudice against hi end designers runs rampant, here.
Good article, Demian.
john curl said:
No, it doesn't make the paint inferior. But it doesn't make the car faster or better handled. That is the point.
Nobody will argue with you if you want a special cap because it looks better 😉 .
Jan Didden
That is not why we use REL caps. IF you have listened to different caps as my associates and I have, over decades, you would know better.
Actually, REL caps are rather drab, compared to many, and have a poor 'form-factor'. However, they are heavy, for their cap value, and highly damped. It might well be that another manufacturer makes as good a cap, and maybe some can buy it cheaper. For example, Wima might be darn cheap for a European to buy, but I don't see any really equivalent cap in this group to compare to.
I use polystyrene, or Teflon, almost exclusively, except for cheaper designs.
My headache is Teflon vs polystyrene, and why there is so much cost difference. YET, I have compared both, from the same manufacturer and found the 'Teflon' cap to be better sounding. Why, I still don't completely understand. I have also talked to the manufacturer about the making of, and the tradeoffs in production with polystyrene vs Teflon. At first, I was told to not bother, by the manufacturer. However, just about everybody in the industry has now heard what I have heard, so I can't ignore it, saving it for special friends and associates.
When it comes to polypropylene, my experience with the SAME manufacturer is that it can be darn good, especially in larger values, such as needed by coupling caps, BUT smaller values, .3 uf or less are served better by Teflon or polystyrene. I have a whole pile of polypropylene caps that I don't have the heart to put into my best designs, but I do recommend them for my cheaper power amps that Parasound makes.
It is MY business to understand what works, and if possible, why. Caps are no exception to this, and I don't recommend anything, just because it looks OK.
Actually, REL caps are rather drab, compared to many, and have a poor 'form-factor'. However, they are heavy, for their cap value, and highly damped. It might well be that another manufacturer makes as good a cap, and maybe some can buy it cheaper. For example, Wima might be darn cheap for a European to buy, but I don't see any really equivalent cap in this group to compare to.
I use polystyrene, or Teflon, almost exclusively, except for cheaper designs.
My headache is Teflon vs polystyrene, and why there is so much cost difference. YET, I have compared both, from the same manufacturer and found the 'Teflon' cap to be better sounding. Why, I still don't completely understand. I have also talked to the manufacturer about the making of, and the tradeoffs in production with polystyrene vs Teflon. At first, I was told to not bother, by the manufacturer. However, just about everybody in the industry has now heard what I have heard, so I can't ignore it, saving it for special friends and associates.
When it comes to polypropylene, my experience with the SAME manufacturer is that it can be darn good, especially in larger values, such as needed by coupling caps, BUT smaller values, .3 uf or less are served better by Teflon or polystyrene. I have a whole pile of polypropylene caps that I don't have the heart to put into my best designs, but I do recommend them for my cheaper power amps that Parasound makes.
It is MY business to understand what works, and if possible, why. Caps are no exception to this, and I don't recommend anything, just because it looks OK.
Teflon is more expensive for several reasons:
PP is made directly from the products of petroleum cracking. The base materials for Teflon need considerably more processing before polymerization.
Fluorination required the handling of and reaction with some very expensive, corrosive, and toxic gases.
Processing temperatures are much higher for the production of Teflon film.
Teflon is far easier to degrade during extrusion. Special materials and processes are needed.
It's much harder to maintain thickness tolerances in Teflon extrusion. It also is much less tolerant of the stresses of takeoff and windup.
PP is made directly from the products of petroleum cracking. The base materials for Teflon need considerably more processing before polymerization.
Fluorination required the handling of and reaction with some very expensive, corrosive, and toxic gases.
Processing temperatures are much higher for the production of Teflon film.
Teflon is far easier to degrade during extrusion. Special materials and processes are needed.
It's much harder to maintain thickness tolerances in Teflon extrusion. It also is much less tolerant of the stresses of takeoff and windup.
Hi,
is Plumber's tape Teflon film?
It looks like threads/fibres of white insulator joined with some bonding agent.
The fibres may be Teflon, but I have no way of knowing whether it is pure/contaminated/something else.
What effect will the bonding agent have on the dielectric properties of the composite?
is Plumber's tape Teflon film?
It looks like threads/fibres of white insulator joined with some bonding agent.
The fibres may be Teflon, but I have no way of knowing whether it is pure/contaminated/something else.
What effect will the bonding agent have on the dielectric properties of the composite?
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