Using choke or capacitor filter in tube guitar amp?
Although power supply of guitar amps is commonly simple, free from modern refinements like electronic regulators , the power supply is the most important part of the amplifier.Because, ultimately, it is the power supply that dictates the limitations of the amplifier as a whole.
Power supply of amp
The power supply of amplifier includes three parts: Power transformer, rectifier , filter. The usage of power transformer is change the wall AC voltage such as 110v or 230v into the sifferent voltages which tubes needed.
The function of rectifier is converting AC into DC.There are two kinds of rectifier according to the electronic components they used: tube and solid state. More about rectifier, we will discuss in other article.
The current pass through rectifier still has ripple which freq is 50 hz or 60 hz , it is possible to cause hum in the amp. So it need the filter to cancel or reduce these ripple.There are two common power filter configurations: capacitor filter and choke filter.
The ripple voltage is often expressed as a percentage of the maximum DC voltage. A typical figure might be 10% for a push-pull amp or 5% for a single-ended amp, though this is highly dependent on individual circuit requirements of course.Bigger filter values for noise makes for stiff rail and sharper attack slopes imo, perfect for that style.
Capacitor filter VS Choke filter supply of amp
A capacitor is a device that stores electrical energy in an electric field. It can be used to absorb and store energy when the AC power is higher than what is needed by the DC load and to supply energy to the load when the AC power is lower than what is needed. The capacitor working is based on voltage, it filt the voltage,remove as much power ripple as possible, and maintain a constant DC value . Capacitor filter is consist of resistor and capacitor. It has the better filting resultion dring working at small current and high voltage statment.
A "choke" is the common name given to an inductor that is used as a power supply filter element. They are typically gapped iron core units, similar in appearance to a small transformer, but with only two leads exiting the housing. The current in an inductor cannot change instantaneously; that is, inductors tend to resist any change in current flow. This property makes them good for use as filter elements, since they tend to "smooth out" the ripples in the rectified voltage waveform. Choke filter (LC) is consist of resistor and choke.It is prefer to big current circuit.
Why modern tube guitar amplifiers replaced choke filter by capacitor?
Many vintage amps used choke filters in their power supply. Fender was interested in maximizing voltage in order to maximize clean output power, so many Fender-derived amps even use a choke-capacitor (LC) filter to supply the power valve screen grids. An LC filter is a second-order filter, so it provides steeper attenuation of ripple than an RC (first order) f