WEET Introduce the Structure, Classification and Applications of Plastic Film Capacitors

WEE Technology Company Limited - WEE are Capacitors Specialist

Film capacitor is also called plastic film capacitor. It takes plastic film as dielectric.

Structure of Plastic film capacitors:

The internal structure of the film capacitor is mainly composed of metal foil (or foil obtained by metallization on plastic) as electrode plate and plastic as dielectric. It is produced by winding or laminating process. Different arrangements of foil and film lead to a variety of structure.

Classification of Plastic film capacitors:

Thin film capacitor is composed of dielectric, electrode, electrode transition, lead out, package, seal and mark.
According to the media classification: polyester film, polypropylene film.
According to the structure classification: winding type, laminated type, inside string type.
According to the electrode classification: metal foil, metallization (aluminum metallization, aluminum zinc metallization), film foil composite structure.
According to the electrode lead out way classification: radial, axial.
According to the packaging mode: box type, immersion type, bare package.

Plastic film capacitors Summary

Thin film capacitor is the closest "ideal capacitor", but it has the advantages of high voltage, high power, high frequency, high stability, high reliability and long service life. It is used in automobile, locomotive, wind power, photovoltaic and other equipment to replace electrolysis.

WEET 3.3uF +/-5% 250VDC MKP Precise Audio Capacitor is the best choice for audio crossover application and speaker system.


WEET How to Select The Suitable Crossover Capacitor For The Audio Applications and Speaker System

WEE Technology Company Limited - WEE are Capacitors Specialist

If you know how to select the suitable crossover capacitor for the audio applications and your speaker system will achieve its maximum performance. 
WEE Technology supplies superior Film and Foil Capacitors, Metalized Polypropylene Capacitors, and Non-Polarized Electrolytic Capacitors that are suitable for the most discriminating audio applications.

Film and Foil Crossover Capacitors: https://www.musicaps.com/WEET-Foil-and-Film-Audio-Capacitors.html

Metalized Polypropylene Crossover Capacitors: https://www.musicaps.com/WEET-Metallized-Polypropylene-Film-Capacitors.html

Non-Polarized Electrolytic Capacitors:https://www.musicaps.com/WEET-Aluminum-Electrolytic-Audio-Capacitors.html

Differences in audio capacitors

Capacitors are the focus of this technical bulletin. There are four basic types of capacitors: electrolytic, ceramic, metallized film and film and foil. (Aluminum Foil and Copper Foil)

Choosing capacitors for crossover networks

The types of capacitors that are commonly used for audio applications include ceramic, electrolytic and film capacitors. These types of capacitors differ in design, construction and performance characteristics. It is usually important to consider the unique needs of your audio application when selecting a capacitor.

The quality of sound produced by an audio circuit is greatly dependent on the audio frequency response of capacitors used. In general, ceramic capacitors have poor audio frequency response. Moreover, the low insulation resistance and relatively high equivalent series resistance of ceramic capacitors make them unsuitable for crossover networks.

Film capacitors are widely used in audio circuits for a wide range of applications. For the optimum performance of a crossover network, film capacitors with low dielectric absorption and equivalent series resistance are commonly used. The characteristics of film capacitors make them the number one choice for audio applications. It is common for circuit designers to use a combination of different types of capacitors.


WEET Shares How to Choose a Best Audio Frequency Capacitor For Crossover Circuit

WEE Technology Company Limited - WEE are Capacitors Specialist

How to choose audio frequency capacitor? These five parameters let you identify the capacitance

Basic information Capacitance, voltage and Temperature

*Electrostatic capacity, expressed in UF. The common ones are 0.1uF, 0.22uf, 0.47uf, 1uF, 6.8uf and so on.

*The working voltage (WV) should be the nominal safe value, that is to say, the nominal voltage should not be exceeded in the application circuit.

*Temperature, most of the common 85 degrees, 105 degrees. Under high temperature conditions, 105 ℃ nominal is preferred. In general, the optimization of high temperature coefficient is helpful to improve the performance of other parameters.

Dispersion factor (DF)

Sometimes the DF value is also expressed by the loss angle tan. Whether the DF value is high or low is related to temperature, capacity, voltage and frequency; when the capacity is the same, the higher the withstand voltage, the lower the DF value. The higher the frequency, the higher the DF value and the higher the temperature.

Equivalent series resistance ESR

The level of ESR is related to the capacity, voltage, frequency and temperature of capacitor. The lower the ESR requirement, the better. When the rated voltage is fixed, the larger the capacity, the lower the ESR. When the capacity is fixed, the ESR can be reduced by selecting high rated voltage. ESR is high at low frequency, low at high frequency, and increases at high temperature.

Leakage current

The smaller the leakage current, the better! The higher the capacitor capacity is, the greater the leakage current will be; reducing the working voltage can reduce the leakage current. Conversely, choosing a higher withstand voltage type will also help to reduce leakage current. Combined with the above two parameters, it is a simple and feasible method to select high voltage withstand varieties under the same conditions; it can reduce internal resistance, reduce leakage current, reduce loss angle and increase life.

Ripple current Irac

Ripple current is a very important parameter for the filter circuit of stone machine. The higher the ripple current Irac is, the better. The higher the frequency, the larger the Irac, and the lower the frequency, the smaller the Irac. According to the traditional view, we need to be able to have a high ripple current at low frequency, in order to obtain good high current discharge characteristics, make the low frequency more solid and full of elasticity, as well as good control and driving characteristics. In fact, at high frequencies, a high ripple current is also very helpful to the positive aspect of the timbre, which can make the high frequency have better extension and reduce the roughness.


WEET WMF Precise Audio Capacitors Low DF is Less Than 0.05% in General Best For Audio Applications

WEE Technology Company Limited - WEE are Capacitors Specialist

The best capacitor types for audio circuits are polystyrene and polypropylene. 
Polystyrene is the first choice, but are only available in values up to .001 uF. 
Above that value, polypropylene is the type of choice, WEET can produce 0.1uF to 100uF capacitance with 250V,400V and 630V voltage.
With nearly the same qualities of dissipation factor (DF) and dielectric absorption (DA) as polystyrene (these are the two capacitor “qualities” that most affect audio applications).

The WEET WMF Precise Audio Capacitors DF is less than 0.05% in general, due to the size of the capacitors, the bigger ones will get a little higher DF.
WMF is the top line of MKP polypropylene film capacitors for crossover, bypass and speakers. Free samples are on request, thank you.


WEET WMF 1uF 5% 250VDC MKP Precise Polypropylene Film Audio Capacitors for Tweeter Low DF

WEE Technology Company Limited - WEE are Capacitors Specialist

WEET would like to recommend the best MKP capacitors for Tweeter to all the audiophiles.

MKP Audiophiler audio grade non-polarized crossover capacitors made in China.  These are the highest quality crossover capacitors available today.  
Rated at 250V, 400V and 630V for plenty of headroom in high-wattage applications. 
Top MKP Audiophiler capacitors values include 1uF, 2.2uF, 3.3uF, 4.7uF, 6.8uF, and 10uF. 

WEET WMF Audio capacitors cross reference to Audyn Cap MKP Metalized Polypropylene

When replacing a capacitor in an existing printed circuit crossover board, order the same capacitance value (in uF - microfarads) as the original.    
Our Audiophiler capacitors are rated at a maximum of 630 volts, which offers significant margin over typical voltages found in audio speaker circuits.   


WEET What is the Meaning of MKP Capacitors and MKP MKT Capacitors Applications

WEE Technology Company Limited - WEE are Capacitors Specialist

Do you know what is MKP stand for? What is the meaning of MKP?
MKP is the abbreviation of metallized polypropylene film capacitor in Germany.
In China factories, some of them call WEET WME Premium Music Cap as MPT , M is for metallized, P is for polypropylene and T is for Shape tube.

Just some basic info. I'll let someone who has used both of them in a TC speak to performance variances.
MKT is a metallized polyester film capacitor, MKP is a metallized polypropylene film capacitor.

Polypropylene:

This type have a very low dielectric loss. They are also an ideal alternative to polystyrene capacitors.

Polyester:

This type offer good stability, a large range of values at low cost and are the most widely used capacitor for general applications.


WEET MKP Polypropylene (PP) Plastic Film Capacitors Used in Noise Bypass and Crossover Applications

WEE Technology Company Limited - WEE are Capacitors Specialist

Plastic film capacitors are widely used in analog signal interleaving, power noise bypass (anti cross connection) and so on. Plastic film capacitor is a kind of capacitor with metal foil as electrode, which is overlapped with plastic film such as polyethylene glycol, polypropylene, polyethylene or polycarbonate from both ends and wound into a cylindrical structure. According to the type of plastic film, they are called poly (ethylene oxide) (Mylar), polypropylene (PP), polystyrene (PS) and polycarbonate.

Plastic film capacitor is a kind of excellent capacitor because of its many excellent characteristics. Its main properties are as follows: non polarity, high insulation impedance, excellent frequency characteristics (wide frequency response), and small dielectric loss. Based on the above advantages, plastic film capacitors are widely used in analog circuits. Especially in the part of signal cross connection, capacitors with good frequency characteristics and very low dielectric loss must be used to ensure that the signal will not be greatly distorted during transmission. Among all the plastic film capacitors, polypropylene (PP) capacitor and polystyrene (PS) capacitor have the most obvious characteristics. Of course, the prices of these two kinds of capacitors are also relatively high. However, in recent years, in order to improve the sound quality of audio equipment, the parts materials used have become more and more advanced, and the price is not the most important factor to be considered. Therefore, in recent years, the frequency and quantity of PP and PS capacitors used in audio equipment are increasing.

The common method of making plastic film capacitor is to take aluminum and other metal foil as the electrode and roll it together after overlapping with plastic film. But in addition, there is another way to make thin film capacitors, called metallized film. The method is to vacuum coat a thin layer of metal on a plastic film to act as an electrode. In this way, the thickness of the electrode foil can be omitted, and the volume per unit capacity of the capacitor can be reduced. Therefore, the thin film capacitor can be easily made into a small and large capacity capacitor. For example, the common MKP capacitor is the synonym of metallized polypropylene film capacitor, and MKT is the synonym of metallized polyethylene film capacitor.


WEET Introduce The Best Audio Crossover Capacitor Factory in Taiwan China

WEE Technology Company Limited - WEE are Capacitors Specialist

When talking about top the audio and music plastic film capacitors factories, we will think about European brands, no doubt these companies put great money on trademark marketing.

However, as the labor cost in their domestic country is high, so they will find China factories to do OEM for them cost down. When they bring in the techniques, they also helped to upgrade the production ability of Chinese factories, the great beneficiary is Taiwan factories at first. Below are some examples for your reference. They do very good in audio capacitors.

http://www.bennic.com.tw/en/filmcap/index.asp

https://www.mdl.com.tw/en/product.html

https://www.musicaps.com/Products.html

Worldwide, Nichicon of Japan, Wima of Germany, ICEL of Italy and CDE of the United States are the top thin film capacitor manufacturers. Among them, Wima products are mainly used for high-quality audio, nichion is mainly used for electronic products, and CDE is a professional inverter film capacitor manufacturer. Others, such as Nissi in Japan, Philips in the Netherlands, and Kaili, Yudian and Huarong in Taiwan, are also world-famous film capacitor manufacturers. In terms of output, Matsushita Electric of Japan, EPCOS of Germany and KEMET of the United States are the world's leading film capacitor manufacturers.

At present, polyester film and polypropylene film are the main dielectric film materials for thin film capacitor in China. Polyester film is mainly used to produce DC capacitor, which is suitable for electronic products with high degree of electronic integration; polypropylene film is mainly used to produce AC capacitor, which is suitable for electronic, household appliances, communication and electric power containers.



WEET Tells You How to Identify Film Capacitors Directions by Marking, Leads or Oscilloscope

WEE Technology Company Limited - WEE are Capacitors Specialist

Except for outer foil marking on the surface of the capacitors, some factories make their capacitors apparently have a shorter lead on the outer part of the foil. If I havent totally got this wrong it is suggested that the outer part of the foil should be connected to the negative side.

The outer foil end is connected to the lower impedance side, in a signal situation like inter stage/coupling this would mean the outer foil end is the input side (previous stage). In a decoupling situation the outer foil end goes to ground (lower impedance).

If you can not identify the outer foil of the capacitor by external appearance, and you also do not own an oscilloscope, we suggest you try below link and find other ways to identify film capacitors directions.

https://forum.audiogon.com/discussions/are-film-capacitors-directional

I've found it much easier to discern the orientation of the outer foil on film caps using TrueRTA spectrum analyzer software on my laptop. The most expensive version of this software (1/24 octave resolution) is only $100, lower resolution versions cost less.

I use the line in connection on the laptop with a simple cable consisting of a mini jack on one end and bare wires for signal and ground on the other, then watch the 60Hz peak on the spectrum analyzer go up or down depending on cap orientation. I also own a Tektronix 20 MHz scope and the TrueRTA method works much better for me.


WEET How Long Does Hi-Fi Audio Component Break-In (Burn-In) Different Ideas From Customers

WEE Technology Company Limited - WEE are Capacitors Specialist

How does Hi-Fi Audio Component Break-In (Burn-In)?
Do new capacitors in a crossover need breaking in?
Capacitor Burn In: correct method? 
How long they need to full "burn in"? 

Some feedback as below from different customers for your reference only.

Customer A:  "Need" is a strong term, but to my ears, new capacitors do change in sound over the first 100 hours. The most noticeable to me listening to Daytons break in is around hours 20-30. I didn't believe it either until I heard it myself. For lack of a better explanation they get less "harsh" and "smooth" out. I'm not an electrochemical guy so I can't fathom the why on it. 

Customer B:  In my experience you’re going to have to let it run for about 6-7 years continuously in order for the capacitors to truly burn in all the way and sound their best. It’s also better if you use classical music to do so because of how dynamic it is, it will really make a major difference.

Customer C: Normaly capasitors need some time to "brake in" or "burn in". Usually it takes about 100-200 hours. Some of capasitors need more - for exampel Teflon caps need over 400 hours.

Capacitor burn in, how long does it really take?

Customer D: Absolute nonsense. If a cap required 50 hrs burn-in to perform correctly that would mean the mfg designed it that way and would include that information in the specs. Anybody seen any cap specs that state: "Requires 50 hours burn-in to reach full potential."? Me neither.