Had the exact same problem. Fixed it in 2 seconds after watching this video by just using a folded piece of paper to poke the connector on the right channel. Didn't even have to open it up! Thanks a lot for helping out
Watched this video on my laptop and not on my mobile phone, and enjoyed it even more. I have some problem electronic devices not functioning so good and are itching to get stuck into it. You gave me a good kick start my friend. Love to see you fixing things. Keep up the good educational videos.
Thanks for making these vids. I'm decent with tubes, but a bit of a rookie with solid state. I learn best by watching others solving problems. You could give me 10 books, and I'd not learn as much as looking over the shoulder of a veteran tech at work for a few hours.
I have an early 80's Sugden A25 amp and I am getting distortion intermittently from either speaker, do you have any idea what that could be, So you can hear the music but it's breaking up?
Awesome! I have the exact same model with that exact same problem. Luckily I havent had the heart to throw it out yet so its still sitting around. Definitly going to try this out and see if I can get some use out of it.
I have the exact same issue with one of my old NAD amps that i picked up at some recycling center. One channel keeps cutting out like that and giving me white noise similar to a out of tune FM radio. But as soon as I give it a few love taps on the side it goes away, so I bet it is the same issue as this one.
I have a similar problem with an amplifier: once the amplifier warms-up I am getting static in one channel, it is volume dependent (I do not hear it at low volume). Any idea what can it be? Thanks!
Hello, interesting video! Would you be able to discuss changing the mains voltage from 220 VAC to 120 VAC (from Europe to NA mains voltage). Thanks in advance!
Thank you very much. It may be simple, but the tapping technique helped me find where the problem was on my digital drums. Losing audio on the left channel. As I don't have a tester and don't know how to use one. :)
Hey there. I recently picked up a used sony receciver on ebay that has a strange problem. It produces static on all of its analog outputs. Hdmi is fine. What do you think it could be?
Bought a few nads, all sounded great. Then i would go online and read about this repair and that repair and get cold feet and sell it before it breaks 🤣 usually for more than i bought it to.
I get occasional static in my left speaker. I have A+B front speakers. Static only in A. Only happens during mid+high range frequencies. Is it my speaker, or just bad recordings? It's rare, but enough to make me go crazy.
Hi 12voltvids. Can i ask you something? I have got an Sony STR 5800 Amplifier built in 1978. As i bought it it was like new. Now 3 years later the left channel sometimes cut out but comes back when i turn volume up. Also this happenes really rarely. What do you think should i do? Trying to resolder the Relais? Also can you give me some advice how i can extend the life of this amplifier? because i really love it and i want it last as long as possible. Just 5 Minutes ago i thought about trying to increase the cooling of the STK IC`s and such things. Or should i leave it like it is ? Would be very nice if you can help me a little bit :)
By the way, the sony was really a luck shot for me. I was searching a good vintage amp because i knew they are most tiumes superior to modern gear. The seller sold it for 25€ to me ( on ebay it is 10 times as much and more for even worse condition ). He probably thought it was just a radio reciever :D
I don't know if you will see this but that issue sounds like the speaker relay (poor contact do to oxidized connections inside it) very easy fix ... a fairly thick paper soaked with regular isopropyl alcohol 90% or better) rub the contacts on both sides and that will make the relay a past memory LOL
This is 5 yrs ago.. but sir i wud like to know about the noise that occurs when you hit or tap a device.. does it does with stk problems? Stk 437 to be specific.. tnx..
I run 2 of those amps in mono.. and i get that static sound many times .. i fix it but going to the switch in the back of the amps that say Fix/var for the power amp and i go back n forth with the switch about 20 or 30 times and clears right up... they get dusty and thats what happens.. knowing that both amps have done it means thats a common problem.. just saying.. you may have done a unneeded repair..
I just bought one of these. Mine does not have plugs for the connectors. All connections are soldered to the boards right from the factory. Must have changed the design at some point in the production run.
Connectors = failure point. Just look at all the trouble RCA, Zenith, Motorola and Philips had when they went to "plug in modules for easy servicing" More like "Plug in modules so you can be assured of regular servicing"
Did a complete re-cap on the unit and changed out the main relay. Added two extra 4700uf filter caps in the empty areas on the PCB and boy does this puppy sing. Bloody smooth sounding amplifier!
just thought of something when your re flowing solder on various bad areas this could make a lot of sense and change your re flowing technique strategically wise, for instance a 3 leg output transistor needs a touch up, do one leg left, go to the other complimentary transistor then do the right leg then do another point somewhere else then do the far right leg then back to other transistor left leg then do another point somewhere else then finish the middle leg , so basically what this technique is doing is waiting for the solder to cool down before applying heat to the adjacent leg of the component, giving the component a better chance at a longer life, so basically never heat the next leg beside what you've just done always go to farther point away to lessen heat in a same area then come back and do the adjacent points , like jumping around rather than staying in one area, message me back on this new thought , thanks mike !!!
probaby corroded or loose connection? deoxit and some hot snot to prevent it working loose.....guessing this before i see the entire video....dont be cruel! also the transistor on the heatsink right near it was loose
I am having the same problem with my Pioneer Receiver VSX-453, static in the left channel more noticeable with the volume knob in zero, no matter if the balance knob is turned for the right speaker only, the static noise is random, it works well for 10 15 minutes and then the static returns and then suddenly goes away. What could be causing this problem?. Thanks in advance for your help.
im curious if you could build a high power amplifier using parts from mutiple other stereos using everything you can from each example (preamp and contollers for it) amps and etc from other
Building a amplifier depends on the skill set of the builder... There are risk factors involved ie getting shocked.. Knowing how to use the components to build your creation and not blow the whole lot and end up with crispy pole of knackered parts. It may be safer to buy a amp off ebay.. But good luck with your projects
Thank goodness it is not a high power Hybrid IC if it is a NPN try a BC182L else if PNP try a BC212L if it is a 2SAXXX or 2SBXXX I don't know will work there as I cannot think of any equivalents, I think that the BCXXX series of transistors are all general purpose.
I was hoping you could help me. I am repairing my 1970s HH Scott 380R receiver. Something failed and took out 5 transistors on one channel. I am thinking a capacitor must have shorted and over biased something and caused an avalanche of destruction/ Can you or anyone else steer me to a website app or website for getting cross-referenced replacements for the Japanese transistors that were used in this receiver? Thank you.
During assembly, if the solder is not heated hot enough, and applied long enough in the wave solder system, you end up with a cold joint. Anyone that knows anything about "joints" know that you need to get it very hot, burning actually to get the desired effect. Now personally I know nothing about that, but my friends that consume said material confirm that this is the case.
Really nice video, thank you for posting! I have an old NAD 317 which also has noise on the left channel. I followed your error searching methods and found three transistors (at least) that acted up when I put the solder iron close to them. My issue now is that my knowledge about transistors is virtually non-exisiting. The transistors in question are of the types TR 2SC1815-Y HFE 120-240 and TR 2SA970GR. Can anyone give any guidance in finding replacements? It would be very much appreciated.
Where on the board were these. Did you resolve it. I’ve a 317 that was given to me with same issue. Static in left channel but does output sound but can hear its not perfect in that channel
@@23chilled Hi. I never managed to solve it. In the end I replaced the amp. However, it has to be said that I am not particularly skilled in this type of work ;)
I had that problem too, I swapped the speakers and proved it was the speaker, was it solder connection or a cap in the crossover I changed the bipolar caps and resoldered everything and it worked. I then did the same with the other one to match them up. Good Luck.
im looking at a made in japan nad 2155 from 1985 i was wondering if it has any sound issues if anyone can help me find someone to fix it? im in north florida but could always ship it somewhere
Connections are > 50% of electronic problems. For the socket/plug from the rear RCA to the amplifier board I have had similar issues where lightly cleaning with a bit of fine sand paper and slightly bending the pins fixes the contact issue. To a comment : Soder = US pronunciation , solder = European, it's a global world !
killmore75 the crows are all pissed off at a bald eagle that is raiding the nest there was about 10 of them chasing it. tomorrow I will be waiting with a camera trained up in the trees as it will probably come back.
Ha ha "the video is done, byeee" you funny sod :-D. I had a very similar noise on a dual hi quality sharp cassette deck, one channel just made a horrible noise. (no it wasnt modern music lol ). After tracking with an audio probe, it turned out to be a interstage coupling capacitor that was trying to be a resistor, it was screwing with the bias of the next transistor. Capacitors are real shitbags for screwing up.
I figured it was a transistor at the start, until I toughed the audio interconnect wire. Then the noise went away, and when I wiggled it, it made a horrible sound as you heard so it was likely some oxidation on the contacts and moving it fix that problem. I re flowed many of the connections on the board just to make sure, and it has been under test. Today is day 3, as I shot the video on Sat, tested it all night sat, tested it again all day sunday, and then published the video, and now today it is still running, no noise. I will send it home later today if it continues to ne quiet.
I do like the modular design of the amp, if one channel goes pop its an easy task to lift out just the pcb. My old pioneer SA-706 has a base board with all the parts on it, even the big black heatsinks sit on it, but it has a trap door :-)
I have an early 80's Sugden A25 amp and I am getting distortion intermittently from either speaker, do you have any idea what that could be, So you can hear the music but it's breaking up?
I have an early 80's Sugden A25 amp and I am getting distortion intermittently from either speaker, do you have any idea what that could be, So you can hear the music but it's breaking up?
I have an early 80's Sugden A25 amp and I am getting distortion intermittently from either speaker, do you have any idea what that could be, So you can hear the music but it's breaking up?
Had the exact same problem. Fixed it in 2 seconds after watching this video by just using a folded piece of paper to poke the connector on the right channel. Didn't even have to open it up! Thanks a lot for helping out
Watched this video on my laptop and not on my mobile phone, and enjoyed it even more. I have some problem electronic devices not functioning so good and are itching to get stuck into it. You gave me a good kick start my friend. Love to see you fixing things. Keep up the good educational videos.
Thanks for making these vids. I'm decent with tubes, but a bit of a rookie with solid state. I learn best by watching others solving problems. You could give me 10 books, and I'd not learn as much as looking over the shoulder of a veteran tech at work for a few hours.
I have an early 80's Sugden A25 amp and I am getting distortion intermittently from either speaker, do you have any idea what that could be, So you can hear the music but it's breaking up?
That toroidal transformer is nice !
Nice repair, again ! Thanks for sharing.
Awesome! I have the exact same model with that exact same problem. Luckily I havent had the heart to throw it out yet so its still sitting around. Definitly going to try this out and see if I can get some use out of it.
What did you clean the circuit board with?
as always Excellent diagnostics and rectification.
thank you.
I have the exact same issue with one of my old NAD amps that i picked up at some recycling center.
One channel keeps cutting out like that and giving me white noise similar to a out of tune FM radio. But as soon as I give it a few love taps on the side it goes away, so I bet it is the same issue as this one.
I have a similar problem with an amplifier: once the amplifier warms-up I am getting static in one channel, it is volume dependent (I do not hear it at low volume). Any idea what can it be? Thanks!
Hello, interesting video! Would you be able to discuss changing the mains voltage from 220 VAC to 120 VAC (from Europe to NA mains voltage). Thanks in advance!
I have a Denon AVR-X2600H with the exact same problem. Been in the shop twice under warranty and no resolve. Aggravating
Thank you very much. It may be simple, but the tapping technique helped me find where the problem was on my digital drums. Losing audio on the left channel. As I don't have a tester and don't know how to use one. :)
@1:31 we call that "percussive maintenance"
Great video! Thanks for sharing!
Hey there. I recently picked up a used sony receciver on ebay that has a strange problem. It produces static on all of its analog outputs. Hdmi is fine. What do you think it could be?
Bought a few nads, all sounded great. Then i would go online and read about this repair and that repair and get cold feet and sell it before it breaks 🤣 usually for more than i bought it to.
I get occasional static in my left speaker. I have A+B front speakers. Static only in A. Only happens during mid+high range frequencies. Is it my speaker, or just bad recordings? It's rare, but enough to make me go crazy.
Thanks for the wonderful video
Nice ending!
Hi 12voltvids.
Can i ask you something?
I have got an Sony STR 5800 Amplifier built in 1978. As i bought it it was like new. Now 3 years later the left channel sometimes cut out but comes back when i turn volume up. Also this happenes really rarely.
What do you think should i do? Trying to resolder the Relais?
Also can you give me some advice how i can extend the life of this amplifier? because i really love it and i want it last as long as possible. Just 5 Minutes ago i thought about trying to increase the cooling of the STK IC`s and such things.
Or should i leave it like it is ?
Would be very nice if you can help me a little bit :)
By the way, the sony was really a luck shot for me. I was searching a good vintage amp because i knew they are most tiumes superior to modern gear. The seller sold it for 25€ to me ( on ebay it is 10 times as much and more for even worse condition ). He probably thought it was just a radio reciever :D
I don't know if you will see this but that issue sounds like the speaker relay (poor contact do to oxidized connections inside it) very easy fix ... a fairly thick paper soaked with regular isopropyl alcohol 90% or better) rub the contacts on both sides and that will make the relay a past memory LOL
This is 5 yrs ago.. but sir i wud like to know about the noise that occurs when you hit or tap a device.. does it does with stk problems? Stk 437 to be specific.. tnx..
Bad connection somewhere.
@@12voltvids tnx much..
I run 2 of those amps in mono.. and i get that static sound many times .. i fix it but going to the switch in the back of the amps that say Fix/var for the power amp and i go back n forth with the switch about 20 or 30 times and clears right up... they get dusty and thats what happens.. knowing that both amps have done it means thats a common problem.. just saying.. you may have done a unneeded repair..
I just bought one of these. Mine does not have plugs for the connectors. All connections are soldered to the boards right from the factory. Must have changed the design at some point in the production run.
Connectors = failure point. Just look at all the trouble RCA, Zenith, Motorola and Philips had when they went to "plug in modules for easy servicing"
More like "Plug in modules so you can be assured of regular servicing"
Did a complete re-cap on the unit and changed out the main relay. Added two extra 4700uf filter caps in the empty areas on the PCB and boy does this puppy sing. Bloody smooth sounding amplifier!
just thought of something when your re flowing solder on various bad areas
this could make a lot of sense and change your re flowing technique strategically wise,
for instance a 3 leg output transistor needs a touch up, do one leg left, go to the other complimentary transistor then do the right leg then do another point somewhere else then do the far right leg then back to other transistor left leg then do another point somewhere else then finish the middle leg , so basically what this technique is doing is waiting for the solder to cool down before applying heat to the adjacent leg of the component, giving the component a better chance at a longer life, so basically never heat
the next leg beside what you've just done always go to farther point away to lessen heat in a same area then come back and do the adjacent points , like jumping around rather than staying in one area, message me back on this new thought , thanks mike !!!
probaby corroded or loose connection? deoxit and some hot snot to prevent it working loose.....guessing this before i see the entire video....dont be cruel! also the transistor on the heatsink right near it was loose
NICE WORK , NICE AMP
You mention a Yamaha you found to have faulty transistor. Do you have a video on this repair please? Thanks
Yes it is on my channel. Don't ask me to search it out you can find it easy enough.
I am having the same problem with my Pioneer Receiver VSX-453, static in the left channel more noticeable with the volume knob in zero, no matter if the balance knob is turned for the right speaker only, the static noise is random, it works well for 10 15 minutes and then the static returns and then suddenly goes away. What could be causing this problem?. Thanks in advance for your help.
Likely cold solder connection in left channel somewhere.
That sounds like an IC wind noise you would have on an old Akai reel to reel.
im curious if you could build a high power amplifier using parts from mutiple other stereos using everything you can from each example (preamp and contollers for it) amps and etc from other
Building a amplifier depends on the skill set of the builder... There are risk factors involved ie getting shocked..
Knowing how to use the components to build your creation and not blow the whole lot and end up with crispy pole of knackered parts.
It may be safer to buy a amp off ebay..
But good luck with your projects
I did have the same issue on a technics amplifier as wel bad solded connection.
Thank goodness it is not a high power Hybrid IC if it is a NPN try a BC182L else if PNP try a BC212L if it is a 2SAXXX or 2SBXXX I don't know will work there as I cannot think of any equivalents, I think that the BCXXX series of transistors are all general purpose.
I was hoping you could help me. I am repairing my 1970s HH Scott 380R receiver. Something failed and took out 5 transistors on one channel. I am thinking a capacitor must have shorted and over biased something and caused an avalanche of destruction/ Can you or anyone else steer me to a website app or website for getting cross-referenced replacements for the Japanese transistors that were used in this receiver? Thank you.
Get NTE Quick Cross on the google play store
Thank you.
What is a cold sawder??? Sorry for the bad spelling.😋
During assembly, if the solder is not heated hot enough, and applied long enough in the wave solder system, you end up with a cold joint. Anyone that knows anything about "joints" know that you need to get it very hot, burning actually to get the desired effect. Now personally I know nothing about that, but my friends that consume said material confirm that this is the case.
@@12voltvids thanks I'm trying to learn as much as I can and your videos are great..
That board looks so simple
Nice amplifier.
This guy is very helpful and knowledgeable however I hate it when people pronounce it"soleder" instead of solder (soder). The l is silent.
ive used a heating gun to reheat bad solder joints (proper amount bad cold solder joints)
Really nice video, thank you for posting! I have an old NAD 317 which also has noise on the left channel. I followed your error searching methods and found three transistors (at least) that acted up when I put the solder iron close to them. My issue now is that my knowledge about transistors is virtually non-exisiting. The transistors in question are of the types TR 2SC1815-Y HFE 120-240 and TR 2SA970GR. Can anyone give any guidance in finding replacements? It would be very much appreciated.
Where on the board were these. Did you resolve it. I’ve a 317 that was given to me with same issue. Static in left channel but does output sound but can hear its not perfect in that channel
@@23chilled Hi. I never managed to solve it. In the end I replaced the amp. However, it has to be said that I am not particularly skilled in this type of work ;)
can i send you my pioneer vsx-d620s for fixing ?
what is it when one speaker is working , turn up the volume then the other speaker kicks in ...? I get this with most amps after time
Dirty pots/switches most likely, so I bet cleaning all the switches and pots will fix that issue.
I had that problem too, I swapped the speakers and proved it was the speaker, was it solder connection or a cap in the crossover I changed the bipolar caps and resoldered everything and it worked. I then did the same with the other one to match them up. Good Luck.
My nad 214 is getting too hot without inputs and speakers also when I ran the power on test
im looking at a made in japan nad 2155 from 1985 i was wondering if it has any sound issues if anyone can help me find someone to fix it? im in north florida but could always ship it somewhere
Nice as always! :)
Nice trick
My first suspect was that connector.
Mine was Escobar!
Mine was Hitler
Ferris Bueller had Audiosource and Carver equipment. No NAD.
Ha ha ha. Good one. Was waiting to see who made the Ferris Bueller connection.
Thanks.
And for a teen, Ferris Bueller had some great top of the line A/V gear for the time.
what's with the bloody annoying dot on the video
What dot? Could you be more specific as to when and where on the screen you see it?
PurpleGhost it dissapeared must of been a you tube glitch
Chinese nad = CHAD
Nice!
Belle video beau dépannage !!!!!!!!!.......???
Connections are > 50% of electronic problems. For the socket/plug from the rear RCA to the amplifier board I have had similar issues where lightly cleaning with a bit of fine sand paper and slightly bending the pins fixes the contact issue.
To a comment : Soder = US pronunciation , solder = European, it's a global world !
Solder - Canadian
I guess you have a baby crow in the neighborhood?
killmore75
the crows are all pissed off at a bald eagle that is raiding the nest there was about 10 of them chasing it. tomorrow I will be waiting with a camera trained up in the trees as it will probably come back.
Ha ha "the video is done, byeee" you funny sod :-D.
I had a very similar noise on a dual hi quality sharp cassette deck, one channel just made a horrible noise. (no it wasnt modern music lol ).
After tracking with an audio probe, it turned out to be a interstage coupling capacitor that was trying to be a resistor, it was screwing with the bias of the next transistor.
Capacitors are real shitbags for screwing up.
I figured it was a transistor at the start, until I toughed the audio interconnect wire. Then the noise went away, and when I wiggled it, it made a horrible sound as you heard so it was likely some oxidation on the contacts and moving it fix that problem. I re flowed many of the connections on the board just to make sure, and it has been under test. Today is day 3, as I shot the video on Sat, tested it all night sat, tested it again all day sunday, and then published the video, and now today it is still running, no noise. I will send it home later today if it continues to ne quiet.
I do like the modular design of the amp, if one channel goes pop its an easy task to lift out just the pcb.
My old pioneer SA-706 has a base board with all the parts on it, even the big black heatsinks sit on it, but it has a trap door :-)
2n 355
I have an early 80's Sugden A25 amp and I am getting distortion intermittently from either speaker, do you have any idea what that could be, So you can hear the music but it's breaking up?
Distortion is usually a failure of one of the transistors in the driver of output stage, or an open resistor or coupling capacitor.
@@12voltvids thank you I will take it to a pro if that's fixable. No idea why there are multiple posts from me here.
I have an early 80's Sugden A25 amp and I am getting distortion intermittently from either speaker, do you have any idea what that could be, So you can hear the music but it's breaking up?
I have an early 80's Sugden A25 amp and I am getting distortion intermittently from either speaker, do you have any idea what that could be, So you can hear the music but it's breaking up?