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Help with noise in tube amp EL34A

Hello
I need some help with a Chinese tube amp that I’m using for one of my turntable setups
It’s a el34A type amp
When nothing is playing, I hear soMe noise in my speakers, it does not sound like a 60hz buzz, or I don’t think it is. I just tried some other tubes in it and still has the same noise
I have meters and a scope, not very handy with my scope, have it for setups input gain for car amps.
What steps and how do I accomplish these steps to track down the source of this noise.
Also one other problem I’m having is that the left speaker channel is not as loud as the right channel. And it’s the same no matter if I’m playing the turntable or cd inputs.
Here’s a photo of the amp, later today I’ll flip it over and remove the bottom plate and take photos of the inside
Thanks for any and all help
P.S. I’m a newbie with doing this type of stuff so please try to dump it down for me lol
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In some cases these chinese amps are full of errors. So please check the schematics and compare it with the connections inside the amp.
Also swap the output signal of your Nikko preamp. It could be the preamp that is noisy.
 
When nothing is playing, I hear soMe noise in my speakers, it does not sound like a 60hz buzz, or I don’t think it is. I just tried some other tubes in it and still has the same noise

Well it's a cheap amp with minimal filtering in the power supply, so getting the noise level down isn't going to be easy. If it's not an issue with music playing, then just deal with the other issues and ignore it.

The channel imbalance maybe the volume pot. Did you try swapping the EL34's to see if the imbalance follows the tubes to the other channel.

Also there is a large thread here on this amp that was active for a while. You may want to post your issues in it.

Boyuu EL34 A9 Tube Amp

jeff
 
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In some cases these chinese amps are full of errors. So please check the schematics and compare it with the connections inside the amp.
Also swap the output signal of your Nikko preamp. It could be the preamp that is noisy.


I’ve tried a different preamp and the noise is still there, with this amp, I can plug a CD player right into it as it has two sets of inputs
Good idea and thanks for that
 
Well it's a cheap amp with minimal filtering in the power supply, so getting the noise level down isn't going to be easy.

The channel imbalance maybe the volume pot. Did you try swapping the EL34's to see if the imbalance follows the tubes to the other channel.

Also there is a large thread here on this amp that was active for a while. You may want to post your issues in it.

jeff


Thanks Jeff. Do you have a link for those post? If so , please post it for me
Yes I’ve moved the tubes and installed new ones as well and still have all the same problems
 
Hello
I need some help with a Chinese tube amp that I’m using for one of my turntable setups
It’s a el34A type amp
When nothing is playing, I hear soMe noise in my speakers, it does not sound like a 60hz buzz, or I don’t think it is. I just tried some other tubes in it and still has the same noise
I have meters and a scope, not very handy with my scope, have it for setups input gain for car amps.
What steps and how do I accomplish these steps to track down the source of this noise.
Also one other problem I’m having is that the left speaker channel is not as loud as the right channel. And it’s the same no matter if I’m playing the turntable or cd inputs.
Here’s a photo of the amp, later today I’ll flip it over and remove the bottom plate and take photos of the inside
Thanks for any and all help
P.S. I’m a newbie with doing this type of stuff so please try to dump it down for me lol
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have you seen this thread there you can find everything you need Boyuu EL34 A9 Tube Amp