Is a Resistor a Filter?

Any topics and questions
Post Reply
User avatar
monoben
Posts: 147
Joined: Wed Feb 26, 2014 11:09 am

Is a Resistor a Filter?

Post by monoben »

Is a resistor a filter?

You know we find resistors in some AC circuits, dose a resistor act the same as a filter would act on the signal in Sunvox?

Also is it a fair comparison to say that a diode in a AC circuit dose to the signal what the Waveshaper dose if I colour the wave graph in full light? (and make sure the symmetrical is set to off obvs) It rectifies the signal?

Also one last thing.. What is a capacitors affect on a AC signal?

I really know very little about electronics engineering so sorry if these questions seem silly.
User avatar
SawZer
Posts: 273
Joined: Sun Jun 19, 2011 2:26 am
Location: Texas
Contact:

Re: Is a Resistor a Filter?

Post by SawZer »

This isn't a complete answer, but a resistor by itself doesn't act like a filter, nor does a capacitor. When you pair a capacitor and a resistor together, they create a filter based on the resistance and capacitance.

https://en.wikipedia.org/wiki/RC_circuit

EDIT: Regarding the use of diodes:
You're sorta right, the "perfect" diode would clip an entire side off of a signal, but what really happen is some signal still comes through. So the effect is like if you distorted a sound but only everything below 0 was affected. Which is why...
Most distortion circuits have 2 diodes, one for each direction the signal flows. This will clip both sides to some extent.
User avatar
monoben
Posts: 147
Joined: Wed Feb 26, 2014 11:09 am

Re: Is a Resistor a Filter?

Post by monoben »

Thanks SawZer.

Seems as though I underestimated how strange the behaviour of electricity is.

I was actually hoping to make a filter in Sunvox without using the filter modules.

Looks like I'm back to the drawing board now.
DaedalusYoung
Posts: 35
Joined: Sat Jan 28, 2012 7:07 am

Re: Is a Resistor a Filter?

Post by DaedalusYoung »

Capacitors act as DC blockers, they won't let a continuous current through. And in certain configurations, capacitors also act like lowpass filters. In electronics, they're often used to filter out the 'ripple' on VCC lines, and they'll be placed close to chips as a bypass capacitor. You will also find this in guitars, where a capacitor wired to the tone pot acts as the lowpass filter.

Resistors only limit current, so not too useful on their own, although you could use two resistors to make a voltage divider. In fact, this is how a volume pot works, it divides the voltage based on a variable resistor value, resulting in lower volume output.

If you also add an inductor into the mix, you have all the components to make any passive filter.
User avatar
Logickin λ
Posts: 165
Joined: Sat Sep 08, 2018 8:31 pm
Contact:

Re: Is a Resistor a Filter?

Post by Logickin λ »

Voltage among all component in RC circuit are dependent to one another, so it is not very practical to make module to act like electronic components to simulate the filter circuit due to the 20ms feedback delay.

For those who didn't saw the FIR filter in the discord group, I am going to give a simple idea about it.

If you want to make a filter in a digital world, all you need is a delay.
In DSP, if you chain all the delay by 1 sample and average the output of all the delay modules, you will get a FIR filer.
If you set the feedback of a delay to any non-zero value, while keeping the 1 sample delay, you will have a simple IIR filter.

However, these are the very simplified explanation just to get the idea, it is worth a topic to discuss FIR and IIR individually.
Post Reply