Hey everyone! Thanks for the views. My first video with over 1K views in under 20 hours. Also, a big thanks to those who answered questions left here in the comments. I can't do it all myself.

@Drdozzer

7 жыл бұрын

I really enjoy your videos! Thanks for sparking my interest for building amps, it's a very rewarding hobby! :D Keep up the good work!

@edrickmendez7978

7 жыл бұрын

JohnAudioTech Hi ..I'm a new subscriber love your videos man..so my question its I'm going to build a custom boombox with a TDA amplifier its says 100w x 2 do you have some video where I can learn how to do this?

@josephkingston9252

5 жыл бұрын

John I purchased a 750 watt ever start inverter, I hooked it to a marine battery, whenever I plug my guitar amplifier and pa system into the inver, a lot of static hum starts, but when I pick my guitar up, quite a bit of the hum leaves but is still there, without getting technical please tell me what I can do to fix it.

@carlosmaestre

5 жыл бұрын

Hi, just saw this page: antiqueradio.org/recap.htm and wanted to question: is it possible to wire an electrolytic backward and have this kind of "hum" in modern sound systems?

Thank you, you have just saved me a lot of time and frustration. I can turn up my LM4780 to max now and with my ear pressed right against the speaker I can only hear the faintest hint of a hum :)

love your videos sir! amplifiers are one of my hobbies so all of this is very interesting and teaching

Great video... we need more like this to help the average techie! Good work

Hi all. I used 100ohm resistors with my good old Creative SBS A220 speakers and succeeded. Noise is gone. Also that did not make any adverse effects on sound quality when I connected my phone to my speakers. Also thank you very much John for this video.

@sutharpiyush71

3 жыл бұрын

Hey, Did you connect a single resistor? In between ground of input or input channel? 🤔

@chinhchinh6265

Ай бұрын

No it does not work. It just lower you hum and audio signal. But still buzz

Just to clarify, you might show what that install looks like on a typical amp board (e.g., parts express) with stereo input. Very helpful video. Thx!

Bro sounds like Tobey maguire😭

@dizzie_vee

2 ай бұрын

Lol wtf bro?😅

This was a nice, simple demonstration of how to potentially kill the ground loop noise in the AUX input in my car. Have to try it out this weekend before I buy a more expensive option.

@sutharpiyush71

3 жыл бұрын

Did it worked for you bro?

Use a small board with the BA3121 it will cancel out lots of distortion caused by ground loop. It uses CMR characteristics of the opamp.

Thank you for narrating. Truly.

Commonly, there are two kind of noise in computer PC: ground loop noise (only if you have different grounds connected) and picking up noise signal from audio cable. For ground loop suppression, just buy ground loop suppressor (basically just using transformer). For noise picked from audio cable, you can shield/wrap your audio cable with aluminium foil and connect that aluminium to ground, works for me.

@pianokeyjoe

Жыл бұрын

Yeah my little wall mount amp will be used for PC and Casio keyboard audio(it is essentially a PC speaker system without the PC speakers , so just the internal amp mounted on a decora faceplate in a switch wall box). I have all the connections ready but there is a 3 pin input terminal that does LEFT, RIGHT and GRD. I have shielded twisted pair Cat5e cable.. no pro audio cables at all. So what is your suggestion to keep possible PA amp hum at bay there?(this also has a mic input just like in a PA pager system).

@rodrigobarrera2666

8 ай бұрын

Hello, I was wondering if cable lengh matter and were to pick the shield if using 3.5 mm audio jack? Regards

@chinhchinh6265

2 ай бұрын

What if it is just noise? I dont connected to any cable but it still noise, buzz

1:18 How Dubstep beat drop be like...

Simple solution yet effective, thanks.

Did adding the resister also shunt the feedback when touching the capacitor?

I have just had a look at my crap system in sunroom. Had bad hum the cheap player had no bass and no controls. So I plugged in a scrap amp , got the tone but also got hum . Now put 1k across both inputs and fixed. I was looking for a hum loop. Many thanks.

I was looking for something like this ...I will try your trick . Thanks !

Thank you for this! I had to put a 2 resistors, one to ground + left and one to ground + right in order to get both channels silenced... got rid of buzzing by 90%

@paulsagoe9582

4 жыл бұрын

Please help me out. +233570306 on WhatsApp

@sutharpiyush71

3 жыл бұрын

How exactly you add resistor with channel + ground? 🤔

@KausikKumaar

3 жыл бұрын

It works but audio quality/volume get reduced

@captainjim1010

3 жыл бұрын

@@KausikKumaar in my case audio quality got better

@KausikKumaar

3 жыл бұрын

@@captainjim1010 ok maybe i am using low resistance will try increasing to 10k

i got a long 5 meter headphone extension cable but it is next to power wire and it hums a lot and when i plug in headphones it pops loud.

Great video - thank you John!

Thanks , it help me a lot, I was tired of shitty noise :)

Yeah it's really work! Thank you. 👍🏼

It works man, i was facing the same probleme. thanks a lot.

Thanks for your recomendations

you save my life, John

So my 5.1 amp Stereo is 7294 ic dual sub irfp150mosfet surround is tda2030 4 ic centere is tda 2030 2 ic ....i have this small noise issue....Which resisters use to reduce noice? ...i am also use shielded cables for all inputs to volume control and amplifier ...

Another way is to use an isolation transformer on the audio or use a larger filter capacitor on the power supply.

@diypasstime7785

3 жыл бұрын

Where should the audio transformer be placed? In the audio input or output?

@jiroyamada1139

3 жыл бұрын

@@diypasstime7785 Input.

So I have a TPA3116D2 Dual Channel class D amplifier board and I'm using it with a separate Bluetooth amplifier and when Bluetooth is turned it makes like a 5k hz noise but when I'm using aux through the Bluetooth amplifier it doesn't make any sound. And I've tried the Bluetooth amplifier on another amplifier but it doesn't make any sound when Bluetooth is connected, what could be wrong?

Awesome fix! It worked in eliminating the irritating hum from my DIY subwoofer amp. As I built the normal stereo power amp first, and then this subwoofer amp, I will have to do the same on the stereo inputs on the main amp? Can this be reduced to one single resistor on the initial input, which is the headphone out from my computer instead of three resistors, one for subwoofer amp's mono-fied input, and the two separate left/right inputs on the main amp board? :/

I builded lots of amplifier with Lm4780 / lm3886 / tda7293 and many class A with always the same humm noise trouble ! I try your tips about 1K resistor between the gnd and signal input that help to reduce but not gone at 100% do you have another tips for build a truly silent amplifier ? thanks in advance ! :)

thank you so much ! you help me with this video .

So how can we do this with the class D aliexpress amps? Not sure where to look on where to put the resistor over the input.

Great fix.It really helped. Thanks bro..

@akuadalahaku6011

5 жыл бұрын

Help me, use resistor between R n L input or R to G?

I'll have to try this on my little mono class-d subwoofer amp in my boat =)

can I add a resistor in the input if I want to amplify a mic level signal from a microphone. I bought a cheap PA system which outputs too much noise, even when using the wireless mic or when connected to bluetooth as a bluetooth speaker

its workinggg. thank youuuuu

very helpful, thanks for the video

woo, that was easy, thanks John!!!

Hello all, I built an amp with TDA7297, when signal is connected but paused, and volume at zero, I hear something similar to radio broadcast. Also I have a power switch with lights that lit when power is on, I notice this light gets dim when I touch the enclosure, which is connected to ground. Can anybody give a pointer?

I cant open my current speaker set up(atleast not without breaking it). Are there thing i can to the 3,5mm to improve it? Like an adapter or something

i have a power amp and when i low the volume the sound is not clear bt when i increase the volume it fine sound.what i will do sir hel me please.. create a video on this..

Hello, I have that horrible noise I connect my turntable to a pre-phono in and out to a sansui amplifier on tape, even if I plugged in the ground wire that horrible sound follows, what can I do

Nice Video ! Truly fix the noise mostly.

Thank u nice explanation

Will this work on PAM8403 amplifier. If yes then what is the resistor value will be?

Hi John. Great Vid. I get the same hum albeit Louder off my Adcom as soon as I turn it on. I did accidentally drop the unit within a box on its side 3ft off the ground. Do you think I may have damaged the caps or need to resolder some points which may have come loose?

I'm having a stranger problem, i have this kind of noise only if I connect an input signal. I've tried everything but it just still here. With 270ohm resistor to ground it goes quiter but on higher volumes very annoying. Anyone any experience about that?

How Dubstep was Discovered XD 1:18

@Rainbow__cookie

5 жыл бұрын

Lol

good video and thank you so much

I have a mini arcade cabinet box with a PI, LCD screen, joystick driver, and small mono amp in it. The speaker is giving this type of hum and is also picking up interference from the pi. The audio cable from the PI to the AMP is already shielded. Would a simple resistor solution work for this, or do i need to shield ether the PI, the AMP or both? It running retro pi in the case, and apart from the audio buzz it's all running quite well. Apart from the buzz the sound level range from the AMP is fine.

That was especially worthwhile John....

How can I eliminate noise/static in my house when I turn on the Treadmill, anywhere in house?

They have 75 hms to 600 hms impedance plug(3.5mm). May I know which one should I use for my v8 sound card? The wire is about 30 meters long

wow that shrieking sound is awesome tho, i might want that to be a pedal effect for my guitar

When you say "across amplifier input", does that mean, i connect both ends of the resistor to the negative and positive of the input? So if I have a stereo input, then I should put on both channels? Connecting the left channel to the ground, and right channel to the ground as well? Like this: L-(1Kohm)-G-(1Kohm)-R

Thank you from Algeria!

Hey I am getting some buzzing from my amp how do i fix it

what resistor value I'm going to use if guitar to amp? any suggestion value of ohms

Hey john, can we use this at each stages, like before preamp, before poweramp etc.

IF someone can help me , i have an active amp circuit like this its just Bi amplified rather then stereo, and outputs for tweeter and Bass are shorted , buzz just like this , i dont get it , Tweeter died so i guess that is shorted , but Bass Works , AMP does not burn when i turn it on , without tweeter , There are 3 ICs Power Amps , i changed the tweeter one , but i guess i changed a working part , and There are 2 voltage regulators , changed both of them , changed caps , Rectifying diodes , and when i check output for bass and tweeter , 3 out of 4 wires have a dead short on them , i dont get it why. Im not very good in electronics , but i just changed parts as they are and it didnt burn up , so i guess i did it good , but i have a short and i dodnt know where it is coming from , since most Chips are changed , i didnt chage Bass AMP ICs , there a re2 of them, but if they were shorted , it would burn up , but it Buzzes just liek this on a big speaker so it must be amplifying , so it works , if anyone knows of some Issues that can be the reason for this , im grateful

Very powerful video

Hello, Boss I saw impedance plug on amazon, will it useful to reduce hum noise? What hms should I choose? Thanks a lot.

What makes the hissing noice in cassette drives can I fix it??

Liked the clip. I would have thought to use a T-Filter. Didn't think to use a low value resistor. Thanks.

Thanks. I was making a circuit for a guitar on a breadboard. Turns out, I just needed to shorten the antenna. I mean shorten the leads to the output jack. Problem solved.

Thank you!♥️

I have hiss like that when I turn on the av reseaver. And when I give volume to 0 the speakers scream. But no audio intput is jacked in. On every input it is hissing. Please help

I have a humming sound coming from my definite technology BP7004. I get humming from my speakers just from plugging in just the power f

What is the IC number you are using, do you give me its Circuit Diagram please...

i have a peavey pa amp head how would i quieting it itss a little hum and alot of wind its 260 watts...great hope u can help me thx alot

If I don't have a board like that, can I solder in between the wires somewhere

does this work with guitar amps

Thanks for sharing sir

This is a great video, great explanation! Thanks @JohnAudioT. I have an issue with an active speaker (B&O BeoLab 8000 with built-in amp). It has an RCA plug for line-in that I want to use. And it has an auto stand-by function which means: the amp & speaker switch on when audio signal is coming in, and it (normally) switches off within 3 minutes after the audio signal has ended. I have a kind of distortion that causes buzzing noise. The noise is too loud for the amp to switch to off permanently. It does try to switch off, but then immediately switches back on again. This process repeats continuously. This happens both when I have no external audio source connected to the RCA connector for line-in. As well as when I have an external audio source connected to the line-in. Though the buzz is a little bit less when I plug an iPhone as audio source to the RCA line-in connector. But even with a source connected to the RCA, there still is a lot of sensitivity. Because when I touch the cable that connects the RCA to the AMP, it immediately switches on again. Next I connected a 10K resistor across signal input & ground input. Without an audio source connected, it even increased the buzzing noise. With an audio source connected, the resistor makes no difference. Any ideas/suggestions?

@JohnAudioTech

Жыл бұрын

When you say nothing is connected to the RCA line in, you mean the cable is unplugged at the speaker side, right? If so, this could mean an internal issue with the amplifier. If it goes quiet, you are picking up noise along the cable. I'd guess the cable is pretty long.

@KolfMAKER

Жыл бұрын

@@JohnAudioTech Thanks John! Correct, there is no external audio source connected to the RCA line-in plug. The RCA plug of course is connected internally to the amplifier. This RCA connector sits on a small PCB and is connected via a 4-pin cable to the amplifier and a circuitry that detects audio signal and switches the power between Stand-by/Off and On. This 4-pin cable is about 15 cm long. If I touch that cable, the amp immediately switches on and the buzz is present. If the amp is on and I then touch the 4-pin cable the buzz gets louder. Also when I touch the RCA connector on the back at the signal tip (so not ground), the buzzing gets louder and there is cracking noise. Same happens when I touch with a screw driver (I hold the plastic part of the screw driver, not the metal). I have another BeoLab 8000 speaker; it doesn't have these issues. Question: do you have any suggestion what next step I should make?

@JohnAudioTech

Жыл бұрын

@@KolfMAKER Sounds like an open ground or shield ground. Check continuity with a multimeter if you have one.

Very nice solution! Simple but effective.

I get a lot of humming while using my phone through the mixer ,, what device ,, which way is the best way around .. which isolator is the best one to use .. (inexpensive

so i have this issue, when i turn up the volume at 50%, the noise from the tweeter and my woofer so high, but when i put the volume to 100%, the noise gone, can you explain why ?, i'm using cheap class D amplifier made in china, using the TPA3116 chip, with 2X50W channel

@Tinker_Box

4 жыл бұрын

Seraph I have the same problem all the time with a bunch of different amplifiers and I haven’t found an answer for that.

you think i can put 1 resistor on a crossover ?

ok, im confused. you gotte bridge the positive and negative leads? wont that short the signal?

The last images in the end was like the berry on the top of icecream :D

L'alimentazione è meglio swiching o stabilizzata?

That sound when he touched the capacitor 😂

@C40V15

5 жыл бұрын

that's a cover. someone?

Where can i find that little sony player ??? Whats the name or number of it ?? Thank you

Thats what i wanted to know! Thanks for upload!

nice thumbnail you got there sir. :-D

@ViralVfxWala

5 ай бұрын

Designer charged 20usd

Couldn't you build a ground loop isolation circuit? Basically you transfer the audio signal into another circuit by magnetic transfer which would eliminate noise on the current line, through a couple of coils, or a transformer...? I know this would eliminate any "leaking" dc currents... Then smooth it out with a few caps?

Perfect !!! 👍

Dang, wish I had seen this 2 months ago. It would have saved me hair pulling on my DIY build.

Nice. Very Good.

Sir i did what you did but didn't work for my 50watts kit amplifier but can the wire maybe affecting the sound of my amplifier cause i use a small wire with thin insulator ,and i use a 12V output charger of portable video player to power up the amplifier- is it not good to use?.

@RexxSchneider

Жыл бұрын

You must use shielded wire for the input signal and ground the shield at one end of the wire.

I've pam8610 12v and it is very humming so how to solve it pleeeeeaaaas tell me !!!!!!!!?????

tthnks very very much

I get humming from BP7004 just for plugging the power in. I have nothing else connecting to it, just power for the built in subwoofer. I check all my connections they are good. I did this with everything connected with and without to to the speakers. Please help I want to if I can save them or sale it off for parts.

@thevinkerry

5 жыл бұрын

try add a fan inside your woofer. i realized the heat sinks were not as effective to cool the transistors. it worked for me.

what cap can add to remove noise from an atx fan? in my tda7377?

@DanubioRodriguez

6 жыл бұрын

in high freq listen noise

Hello..im sitar player ..i also play electric sitar....i have a same problem.....can send me a circuit diagram to stop humming and which component use in the circuit please help me

nice tip !!!

what is the no of components

How about the volume, it would be decrese or go down right? Tx u sir 🙏

This works because you are shorting part of the input into ground through resistor, which makes you amplify less noise. However you also amplify less input, what means that you just lowered the volume. If this was a "simple and no-loss solution" each and every datasheet for an amplifier would included this input resistor as a default part. This obviously is not the case. What you can do as a "lossless" solution is to use special input jacks, which when there is nothing connected to the input short inputs to ground. This causes no hum when nothing is connected and no loss when you actually connect something. You can easily check there is no hum for almost any amp when you connect input connection to ground. Many guitar amp input connectors have this, this is why when you do not connect a cable to the input there is no hum and when you connect one without a guitar at the other end the hum is there and effect is the same as in the video. There are also other factors like cable shielding (especially with very high gain amps), how ground is laid out in the amp circuit, filtering etc. Overall I would not recommend this, since you are removing hum, by lowering the volume, which does not make much sense...

@lunarchsbrain2125

6 жыл бұрын

XaFFaX.tk I don't notice any difference between the input with or without resistor, even if I put it while playing. However I have to use a 200ohm resistor to remove the noise, could that damage the input? With an higher resistance the noise remain the same

@codebeat4192

6 жыл бұрын

I don't understand the thumbs ups. Maybe you have to dive into the depth of electrons, electrons flow to the path with the lowest resistance. I think you did it wrong by placing the resistor in serie and not parallel, in serie you are right (lower the input by resistance), in parallel you are wrong. The resistor in parallel avoids a floating state (not connected) and acts actually as a pull-down resistor, it simulate something is connected. In fact it stabalize the floating state and suppress noise. 10k is very common because there are also 10k pots. When you connect a source with only a resistance, lets say 300 ohms, the electrons take that route. I think you connect it the wrong way.

@redakaysoumi3277

6 жыл бұрын

yes you're right it's just a pull-down resistor and it'll work for most cases to avoid a floating state

@researchandbuild1751

6 жыл бұрын

His solution is 100% valid. If you use a high value resistor like 1meg ohm, it actually can help "short" EM interference to ground by forming a non-floating state. Meaning the amplifier will stop picking up "RF" EM noise. And in fact it is a recommended practice to never leave high gain inputs floating. Since the resistor is a high value, it will have little effect on any normal input signal since those signals are much larger than the noise EM signal. This video is perfectly accurate and is a valid solution. It's not going to cut the gain down hardly at all.

@rich1051414

6 жыл бұрын

This pulls down the floating voltage. It isn't just reducing the volume. The noise is of MUCH less current than the actual input, and this works to filter off the low current voltage overlapping the signal. That isn't the same as lowering the volume. On the other side of the input is a buffer which will compensate for your resistor to ground. There is nothing compensating for the noise getting dumped to ground.

is this work with usb bluetooth module receiver also? lm given 5v power through 7805. while playing bluetooth music its making high noise.

@ryantoomey611

6 жыл бұрын

I have the same problem with a Bluetooth module as well.

Why in some audio amplifier boards the value of capacitor at the ripple rejection pin is reduced than specified in the datasheet of that audio IC ? What will be the effect of it on the amplifier ?

@JohnAudioTech

4 жыл бұрын

A lower value capacitor would mean lower ripple rejection. However, if the circuit is powered from a battery or a well filtered supply, lower ripple rejection may not be an issue.