Hello everyone !
I build gainclone with audiosector parts.
I buy big toroid transformer Avel Lindberg.
I build all my amp with twisted cable "normally" for reduce the noise.
The box is in aluminium
etc...etc...
When I start the gainclone I have background noise (60 hz).
Do you have TIPS to kill this noise ?
ex: nF capacitor in parallel with the 1500uF or other TIPS ?
I know many people have this trouble with her first gainclone.
P.s. it's not only when the preamp source is pluged on my amp.
it's ALWAYS !
Thanks for your HeLp !
Nick
I build gainclone with audiosector parts.
I buy big toroid transformer Avel Lindberg.
I build all my amp with twisted cable "normally" for reduce the noise.
The box is in aluminium
etc...etc...
When I start the gainclone I have background noise (60 hz).
Do you have TIPS to kill this noise ?
ex: nF capacitor in parallel with the 1500uF or other TIPS ?
I know many people have this trouble with her first gainclone.
P.s. it's not only when the preamp source is pluged on my amp.
it's ALWAYS !
Thanks for your HeLp !
Nick
Hello all,
I am like Nick. i have different details though. I hope we don't become confused with the type of gainclone.
I have recently constructed a gainclone (the BrianGT). I can say that the GC design was interesting for me because I had always wanted to construct a OTL amp and the designs are very similar - coincidence? Also I had never built a solid state component before or haven’t built anything for many years.
I can say that the audio characteristics are very impressive and I will experiment some more.
For now I only have some bookshelves and a pair of full-range in bass-reflex. I prefer the sound of the full range but have one concern, there is some high back noise with the full range - I believe because it is a very sensitive driver because there is less for the bookshelf. I have no audible hum (from the PS) therefore I would like to know if somebody has correctly filtered this noise or if this is possible. I have already viewed many subjects in this forum but cannot manage to conclude with this exact objective.
I have decided not to use a potentiometer but have not yet placed any input resistor. I am using a simple passive preamp with attenuator (10K) and have also tried the sound card of the PC and the noise always remains.
Thanks in advance for your advice.
M
ps. The photos I have are too large to be posted (only 800KB)
If you provide the email, or another method, I can then send
I am like Nick. i have different details though. I hope we don't become confused with the type of gainclone.
I have recently constructed a gainclone (the BrianGT). I can say that the GC design was interesting for me because I had always wanted to construct a OTL amp and the designs are very similar - coincidence? Also I had never built a solid state component before or haven’t built anything for many years.
I can say that the audio characteristics are very impressive and I will experiment some more.
For now I only have some bookshelves and a pair of full-range in bass-reflex. I prefer the sound of the full range but have one concern, there is some high back noise with the full range - I believe because it is a very sensitive driver because there is less for the bookshelf. I have no audible hum (from the PS) therefore I would like to know if somebody has correctly filtered this noise or if this is possible. I have already viewed many subjects in this forum but cannot manage to conclude with this exact objective.
I have decided not to use a potentiometer but have not yet placed any input resistor. I am using a simple passive preamp with attenuator (10K) and have also tried the sound card of the PC and the noise always remains.
Thanks in advance for your advice.
M
ps. The photos I have are too large to be posted (only 800KB)
If you provide the email, or another method, I can then send
I had some pretty bad hum from my last amp build. turns out I had about 4 things all working against me. Not sure if anything I did will help you, but I'll post my experience.
My first hum came from my chosen source, my computer. easily fixed by switching out the source. I knew it was the source because it got louder when I turned the potentiometer up.
My second hum issue was with improper grounding and isolation of my switches. they were grounding to my aluminum case.
My third hum came from my potentiometer as a part of the ground loop hum, again grounding to the case
My fourth hum was my headphone out, yes, once again, grounded to the case.
Basically, i had 5 ground points strewn around the case. I removed the entire amp assembly from the case and there wasnt a bit of audible hum. Admittedly, this is with a tube amp, but the principles are the same. when i do finally put it all back together I'm going to isolate everything that caused ground issues from the case with teflon, or build an entirely new face plate. Anything to keep the case from turning into a ground loop nightmare.
-Jared
My first hum came from my chosen source, my computer. easily fixed by switching out the source. I knew it was the source because it got louder when I turned the potentiometer up.
My second hum issue was with improper grounding and isolation of my switches. they were grounding to my aluminum case.
My third hum came from my potentiometer as a part of the ground loop hum, again grounding to the case
My fourth hum was my headphone out, yes, once again, grounded to the case.
Basically, i had 5 ground points strewn around the case. I removed the entire amp assembly from the case and there wasnt a bit of audible hum. Admittedly, this is with a tube amp, but the principles are the same. when i do finally put it all back together I'm going to isolate everything that caused ground issues from the case with teflon, or build an entirely new face plate. Anything to keep the case from turning into a ground loop nightmare.
-Jared
gainclone
thanks for your ground loop answer
BUT
I'm disapointed to have many many ground trouble with this VERY BASIC AMPLIFIER.
When you take a look to the (3500$US) GAINCARD UGLY circuit and power supply with EL transformer.
I don't understand why when you take better parts you have trouble.
EL transfo (gaincard) VS toroidal (gainclone)
cheap parts VS best parts. etc.....etc.....
ByE !!!
NickThevoice
Gainclone RULEZ !!! hiihihi huummmmm i'm not sure
thanks for your ground loop answer
BUT
I'm disapointed to have many many ground trouble with this VERY BASIC AMPLIFIER.
When you take a look to the (3500$US) GAINCARD UGLY circuit and power supply with EL transformer.
I don't understand why when you take better parts you have trouble.
EL transfo (gaincard) VS toroidal (gainclone)
cheap parts VS best parts. etc.....etc.....
ByE !!!
NickThevoice
Gainclone RULEZ !!! hiihihi huummmmm i'm not sure
Could you post some pictures? perhaps we can determine the problem by looking at the build. you can email me at narcissist69@hotmail.com and I can resize them for posting.
No matter how good the parts are, one small mistake can change how good it sounds. Have you tested the amplifier without the aluminum case?
-Jared
No matter how good the parts are, one small mistake can change how good it sounds. Have you tested the amplifier without the aluminum case?
-Jared
Posting these for mavallarino to help determine possible noise areas. More eyes are better than my eyes
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An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Nice cases!! Just like mine, only smaller!!
http://www.diyaudio.com/forums/showthread.php?s=&threadid=92673
Looking at the photos it looks liek your Chassis Ground is connected to your power ground in the photo of your amp board (The top one), i.e. the green and yellow cable and the brown cable are the wrong way round. Whilst I appreciate that they go to the same place on the board, it is worth giving the whole thing another check over to make sure all the components are in the right place and wires go to the right place.
Hope you find this useful.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=92673
Looking at the photos it looks liek your Chassis Ground is connected to your power ground in the photo of your amp board (The top one), i.e. the green and yellow cable and the brown cable are the wrong way round. Whilst I appreciate that they go to the same place on the board, it is worth giving the whole thing another check over to make sure all the components are in the right place and wires go to the right place.
Hope you find this useful.
Grounding
Thank you for posting the photos.
The boxes are reused but they are made here by an italian company.
The grounds I think are ok (green to yellow - the terminal is slightly twisted). It is difficult to see in the photo. I may not have grounded to the chassis but the power ground is connected.
The noise isn't necessarily ground noise... it is background white noise.
I would like to know if there are other ways of filtering.
Thanks again and kind regards,
MV
Thank you for posting the photos.
The boxes are reused but they are made here by an italian company.
The grounds I think are ok (green to yellow - the terminal is slightly twisted). It is difficult to see in the photo. I may not have grounded to the chassis but the power ground is connected.
The noise isn't necessarily ground noise... it is background white noise.
I would like to know if there are other ways of filtering.
Thanks again and kind regards,
MV
Still noise
Hello ianpengelly,
I have re checked the grounds. All ok, it only seems incorrect but everything is wired to the correct connection(s).
Can I possibly connect a resistor to ground? Any filtering techniques to consider for the inputs? Again I am using no pot.
I have not, although, connected ground to case, only to the power. May this be a problem? I have looked at the same implementations and they have no problem.
Thanks again and kind greetings,
MV
Hello ianpengelly,
I have re checked the grounds. All ok, it only seems incorrect but everything is wired to the correct connection(s).
Can I possibly connect a resistor to ground? Any filtering techniques to consider for the inputs? Again I am using no pot.
I have not, although, connected ground to case, only to the power. May this be a problem? I have looked at the same implementations and they have no problem.
Thanks again and kind greetings,
MV
I see only two wires runing from the PSU boards.... where is 0V?
edit, oh wait it looks like the led wires....
Still not sure the photograph is 100% clear especialy around the terminal block and the wireing between it and the PSU pcb.
You can try adding a second ground wire from the - tab on the RCA to power ground star
edit, oh wait it looks like the led wires....
Still not sure the photograph is 100% clear especialy around the terminal block and the wireing between it and the PSU pcb.
You can try adding a second ground wire from the - tab on the RCA to power ground star
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