How to add a volume control to your audio amplifier project

I have this chinese bazooka tube style bluetooth speaker that has an FM radio. When I turn the radio on it blasts at full volume and I have to turn it down. Is there any way to add in a potentiometer to the speaker wires to allow adjustment of the volume? I bought a kit of pots and none of them worked. I think I have the wrong ones. the 5k one sort of worked but no sound until 3/4 of the way up then full volume. I will be using only two of the wires. I just want to vary the audio signal going to the speaker

Is input impedentance same as input resistance? For mine (dta2822d) its 100k ohms so i need to use 50k ohms resistor?

Dude! Friggin thanks brother 🙏

How did i end up here again, five years later? dear oh dear :D

So just checking: we replace said resistor with our potentiometer, connecting the outer leads to the input and ground with the output to the input of our amp.

That makes sense! Because, like you said, there is a voltage divider affect, so the signal is sort of split between the ground and the amp input. THAT'S why the same guitar pickup wil sound different between 250k pot, 500k pot, and no pot!

very informative, big up!

I always heard linear was better for audio (mainly for car audio / bass amplifiers ) than Log pots.

I hope you can still answer my question here JAT:) Awesome videos ive been binging on them since last year when I got into audio. I have a tube preamp (buffer) a 6j1 variant you have reviewed and I think the volume put attenuates the signal from my DAC. I have connected that to a power amplifier with an input attenuator to the power stage directly as disabling tone/preamp controls, I can still control the volume. How should I adjust the two volume knobs? Max out the volume on the 6j1 preamp and control it from the power amp or the reverse? the power amp uses a stepped attenuator and the preamp uses a carbon wiper i think. its says b503

What value pot(potentiometer) should we use for volume ,bass n treble individual??

How can i select the right pot value to a certain amp impedance?

1. If the source signal is very strong or having high gain, then will adding higher value potentiometer like 100 k reduce distortion or clipping at maximum volume when potentiometer is turned fully ?
2. If I don't get potentiometer according to the input impedance calculation as you told then what value should I use ? Suppose the input impedance is 30 k but I am not getting 15 k , so can I use 22 k which is available ?

THANKS JOHN VERY HELPFUL TO ME

John, Great video. A couple questions from someone over their head: I’ve made a couple lm1875 kits with your dual voltage source circuit, both inspired from another vids of yours and want to add volume control. Does a 2.2k Pot sound right and does the ground go to the virtual ground?

thanks

Hi,
Thank you very much for the detailed video. But a question popped up after watching it, hope someone will answer. Why do we need to connect the ground to the pot, can't we connect just input?

I want to add volume knob to my digital deck in car instead of pushing buttons I’d rather have the volume knob any ideas of how I can hook up?

Hello. Hope you can help me?
when I connect a stereo potentiometer correctly to an amplifier, there is a short circuit between R. L. on the output when I turn the potentiometer to one side. this is because minus GND. on
R. L. is connected. together.

Miter stick goes to amplifier and one side is audio input and the other side is GND

you ruin the stereo image in the music!

Fantastic video. I always wanted to know. I think I could do it now. Thanks John.

Hi John. I have a TPA3118 mono module. I modded it, decreased to 20db gain. I added a potentiometer for volume adjustment. The pot when full and zero level no noise but at middle levels i m hearing noise. How can i eleminate this problem?

Nice work as usual

Does JohnAudio reply to comments?

Really enjoyed your video. I have a question. I have a set of RCA’s going from my car stereo to a amplifier. The signal playing through this channel is only bass, about 100HZ and lower. On some songs the bass is too strong so I wanted to hook one of these pots to reduce the signal. Am I correct to get a dual A50k ? There is a left and right signal on that channel. Thank you for any help

Need help adding dual individual volume knobs to control two separate channels and need help. I'm open to a DIY and can solder....but would like easiest and cleanest way possible with a budget of say around $30

So I have two bass shakers/transducers installed on my couch. They are single voicecoil 8 ohm 300 watt rms max each. I will be running them in their own channel into a crown xls 1502. I would like 2 volume controllers to adjust the intensity essentially of each shaker individually.

The amp has built in band filter so I will be using that to get only the desired frequencies from movies.

I have found some zone volume control boxes but cheapest is around $60 and says it can only handle 100w.

I thought about using a dual wall mount plug but also only does 100 watt. I found single 300 watt but $50+

I thought about using a passive line mixer there are a few 4 channel ones for around $30 but they only have single coax input and only one coax output. (The crown amp accepts XLR which I won't be using but also accepts bare speaker wire or banana plugs

I'm thinking about using a RCA bass knob adjuster $7 x 2. They have + - for each in and out. Thinking to splice the positive negative to speaker wire. then plug in the other + - to each channel on the amp directly where the speaker wire normally hooks up to the channel.

Will this work? If so, how can I tell to get one that is good enough for the 300 watt rms per channel that will be passing through it? Also hopefully I can find specs to find one that is a audio taper but if not does it matter too much? if this will work any other cons I should know of?

Or any other better routes or options? Any replies from people with knowledge would be very much appreciated. Cheers!

I have a pot that has 7 lugs. 6 are stacked so it is a dual but the 7th is off to the side by itself. Is that a ground? Would I use that to ground the other ground lugs or leave it alone?

Was wiring a volume pot today & totally remembered the right way to do it without even thinking. For me to remember after randomly browsing this video means you did a great job of explaining :p.

Nice! I'm making a volume adjustment knob for my desk since I like to fiddle with the volume all the time

Have seen people adding a cap to the Volume Pot with an intention to reduce treble bleeding (?) Or DC protection.. Does it really needed to do so? Thank you

thanks for explanation; what pot should i use for smartphone to tda8561q amp? 47k or greater? max output signal of the phone at 1kHz is 900 mV

Interesting but off topic. I suggest you rename this video to something like 'How logarithmic and linear potentiometers works.'

I have an LA4440 amp board and according to its (LA4440) datasheet it's input resistance is 30 K. I connected a 47 K POTMETER but I can't increase the volume to maximum as there's distortion if I do that. According to you, the volume pot should be half the input impedance but I am not getting a 15 k pot here , only 10 k, 22k and 47 k pots I am getting in my local shop. When I reduce the volume of the usb mp3 module I am using as source, the distortion goes away but I can't use the source volume all the time as its not smooth. So tell me what to do to reduce distortion while increasing the volume to maximum ?

Volume control iPad

Consider: in-line volume control; RCA - IN - "Source" jacks to RCA - Output jacks: As I recall, most home HiFi RCA outs range around 10K, so... 10K audio pots... RCA "source" center to pot Pin 1("IN"), Pin 2 to RCA center "OUT" , RCA shielding, both "source" + "OUT" to Pin 3...
or isolate RCA shielding "source" from RCA shielding "out" with cap? (Gnd lift at in (source) jacks or out jacks?)

I thought I knew this after all these 40+ years since I was a teen. Nope. thanks for straightening me out! I remember working on a electric guitar years ago and I didn't ground the volume pot ground to the case of the pot. I remember it had hum when I wasn't touching the metal on the guitar.

Thanks for this video, dude.

Thanks for this video :)
Not many make videos explaining such small topics in such lucid manner.

I've watched a dozen videos on this subject and they are all the same so, I connected my audio pot this way and the result is virtually no volume until the last 10% of rotation. In that last 10%, I go from nothing to full volume...however...if I reverse the leads, so that right is low and left is high, the graduation ratio is perfect. Do I need to use inverse log pot to resolve this issue?

How would I go about creating a balance for my speakers just two pots?

The exact info I needed for a project. Thanks for the crisp and clear info delivery. Not a second wasted. I am going to check out your other videos. Thanks again.

Yes, Thank you. Well explained and of great help to me.

Where should I connect the amplifier input if I have an Ic that has 5 pins, there’s a non and inverting one

I am using the ne5532 opamp and get low volume signal at the output when the opamp is NOT powered. How do I fix it?

My input source is a phone connected via Aux cable.

I forgot to solder ground wire to the case of the potentiometer and one of the audio amplifier IC in my homemade amplifier system burned out because of electrostatic discharge, only by touching the knob. It is very important to solder ground wire to the case.

Thank you for posting this info it brings a lot to light.

In this noisy RFi world do you think it would be advantageous to add a low pass network - say 50-100Khz - at the amp input? I knew this stuff 35 years ago but a confirmation refresher is always welcome. Sandy.. ( BTW my Xfinity X1 box analog audio out appears WAY above the 2V p-p max std and overloads my Wireless headphone input. Thinking a simple voltage divider in the cable box to attenuate the signal - not the best place but no room in the headphone transmitter base .

hey jhon, can I use two pots one for left and one for right channel insteal of single 6 pin pot?(I would like to use two 2.2k pots for my lm1875 with 7.5k input resistance)are there any disadvantages of it?great explanation btw!

Hey, you make great videos ...
Any idea how to solve my problem.
I have TDA7297 amplifier thay I buy at Ebay, with 50k volume potentiometer.
Situation without input signal. If potentiometer knob is in middle position I get noise, but when knob is all the way left (MIN) or right (MAX), noise is disappearing ...

I enjoyed your video. It was very helpful. Thank you!