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How to solder potentiometer to speaker? Answered


the speaker for my alarm system is too loud, so i soldered this adjustable resistor (that i plucked out from my headset) on to the speaker.

but somehow, the adjustable resistor only works as a resistor, i cant use it to control the volume.

how can i solder it so that it works ?

and btw potentiometer = adjustable resistor ?




Best Answer 8 years ago

If you cannot adjust the volume, you've got the leads connected to the wrong pins. That appears to be a pretty standard-issue stereo (two-channel) audio pot, with two inputs, two wipers, and a common ground. These pins are Input A, Input B, Wiper B, Wiper A, and Ground, in order, but I don't remember if that's looking at it from top or bottom. Since the volume attenuation is constant, I'll assume you have pins connected between one of the Inputs and Ground - which regardless of dial position always has a constant resistance. Connect the wires between an Input and Wiper to accomplish what you want (pins 1 and 4, or pins 2 and 3). To do this truly correctly, the input would be connected to an Input, the speaker (White wire) should be connected to the Wiper, and Ground should be connected to both the other speaker terminal and the other input line (Black wire). Note what the other commenters have said, this sort of potentiometer is not designed to absorb the power of an amplified signal. The speaker is only rated at 0.5 watts which doesn't seem like a lot of power, but a pot this small may only be rated for 0.1 watts or less, and will be very unhappy (read: burnt) given much more power.

This is not the right way to do it, as gmoon says - they're not designed as volume controls, do not handle much power (without burning).
You could use a switch with fixed-value resistors, or hack into the part of the clock circuit that drives the speaker and add the volume control to that.
Or put tape over the clock-case (where the speaker is)


Hi, but is my diagram OK?

It would work on a piezo, but for any reasonable amount of current you'll find a spot on the potentiometer where it works, it gets hot, burns a hole in it and stops working. gmoon explains this fairly well.


How it looks now.


Hi THANKS for all the help I tried out mhkabir's method, but the same problem was still there. So i tested every lead on the pcb as told by themike and one of them worked! mhkabir your diagram was great, straight forward and easy to understand! and thanks XOIIO, gmoon and lemonie for the advice. Thanks fujiapple


8 years ago

Volume controls are wired as voltage dividers--one end of the POT is the incoming signal, the other end is connected to ground, and the center wiper is the (divided) out-going signal.

However, for sound applications it's best to place the volume control before the amplifier.

Why? Because most POTs have power ratings of less than 1 watt. With even small amps outputting 5 to 10 watts, the POTs would be toast.

(There is one type of after-the-amp volume control-- an attenuator. They require a high-wattage POT called a rheostat...)


8 years ago

Well, I'm not too fammiliar with those types of potentiometers, I use 3-pronged ones. Then you solder the input to the middle, and one of the sides will be the output, depending on how far the knob is turned. Btw yes a potentiometer is an adjustable resistor basically. Look through old radios and clocks, something that has large knobs to find some potentiometers. Hope I helped!

To implement it on a three pronged potentiometer, a 'variable resistor' in better words, just attach the wires on prong one and two,and join three and two.Simple!

Here is what I drew up for you.Use an 1k potentiometer. Any idea what the signal source voltage is?

speaker potentiometer.bmp

You will just have to do this.Attach one lead from the potentiometer to one of the leads on the speaker. Now just attach two wires, one from the speaker and one from the other end of the potentiometer to the sound source.Simple! Have fun! Cheers kabir

Hurm i got this from my old headphones, its used to adjust the volume. I plucked out the connnecting wires and soldered 2 new ones as seen above. Will bad connection cause it to malfunction ? How do i solder speakers ? Can i just solder the 2 (red/ black) wires to the speakers end ? Or must it be before it ? Sorry i really want it to work. Its currently too loud, and if i attach this potentiometer it gets too soft. i want to be able to adjust the volume so that it can be louder in the day and softer in the night.. Thanks