Hi, could you tell me what you think of the hiss of my amp?
I tried to swap the preamp tube but nothing change. I also tried to remove first V1, and not hear anything, after V2 and not hear anything, same with V3.
I soldered a shielded cable to connect input jack to V1 and soldered the two 68K resistor directly to V1 pin.
Frankly I do not know what to do!!
Any idea?
Please, see this video until 45 sec.
http://www.youtube.com/watch?v=ngVgonogacE
Thank's to all
Bassman 5F6A normal hiss or too loud?
Moderators: pompeiisneaks, Colossal
Re: Bassman 5F6A normal hiss or too loud?
The humming that stops when you grasp the plug would suggest to me you have grounding problem.
Either with the house wiring or a ground in the amp.
It doesn't sound like a hiss which is usually a result of gain but more like a 120Hz type noise that is usually a result of poor filtering or a problem with the guitar.
Can you tell us more about the amp?
I know you said it is a Bassman 5F6A, but did you build it?
Did it ever not do this?
What guitar is it?
Either with the house wiring or a ground in the amp.
It doesn't sound like a hiss which is usually a result of gain but more like a 120Hz type noise that is usually a result of poor filtering or a problem with the guitar.
Can you tell us more about the amp?
I know you said it is a Bassman 5F6A, but did you build it?
Did it ever not do this?
What guitar is it?
Tom
Don't let that smoke out!
Don't let that smoke out!
Re: Bassman 5F6A normal hiss or too loud?
The hum when I plug the cord now is resolved. It was a groun loop caused by input jack nut that touched the chassis.
What worries me is the first noise, when I turn the vol pot. The amp is myself building 5F6A.
The noise appears only when the vol pot is at 7 or more and with the bright vol pot is smaller than normal vol pot.
Exclude the guitar because the noise there is also without guitar.
The noise seems a breath.
What worries me is the first noise, when I turn the vol pot. The amp is myself building 5F6A.
The noise appears only when the vol pot is at 7 or more and with the bright vol pot is smaller than normal vol pot.
Exclude the guitar because the noise there is also without guitar.
The noise seems a breath.
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Milkmansound
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Re: Bassman 5F6A normal hiss or too loud?
It's hard to tell how loud that noise is from a recording - it can be that the noise is very quiet but the recorder is very sensitive. Or the other way around.
If you open up the volume pots on any amp, there will be noise. There's a lot of gain which amplifies a lot of rf noise and heater noise. You can try adding DC to the first tube stage heaters - that will get the low stuff out - but the hiss is always going to be there.
I also recommend DC referencing the heaters on an amp with more than 5W or so. That really helps with modern production tubes which are quite noisy compared to their vintage counterparts.
I wouldn't sweat it if the amp is a little noisy when cranked up like that - think about how loud the guitar signal is going to be on top of that noise. If you want an amp that's dead silent on idle at full gain you may want to reconsider using tubes
If you open up the volume pots on any amp, there will be noise. There's a lot of gain which amplifies a lot of rf noise and heater noise. You can try adding DC to the first tube stage heaters - that will get the low stuff out - but the hiss is always going to be there.
I also recommend DC referencing the heaters on an amp with more than 5W or so. That really helps with modern production tubes which are quite noisy compared to their vintage counterparts.
I wouldn't sweat it if the amp is a little noisy when cranked up like that - think about how loud the guitar signal is going to be on top of that noise. If you want an amp that's dead silent on idle at full gain you may want to reconsider using tubes
Re: Bassman 5F6A normal hiss or too loud?
Another thing you can do is re-locate your V1 grid resistors right on the socket this will be less noisy.
Tom
Don't let that smoke out!
Don't let that smoke out!
Re: Bassman 5F6A normal hiss or too loud?
The resistor grid are the 68K? If yes, I've already done and in fact the noise is sligtly less noisy.
Today, a friend on mine came to my house and told me that your Fender De Ville has identical breath.
I think of leaving things as they are and enjoy the wonderful sound of my amp. It is very great and the breath is only at volume up. The sound of guitar is more loud than noise.
Today, a friend on mine came to my house and told me that your Fender De Ville has identical breath.
I think of leaving things as they are and enjoy the wonderful sound of my amp. It is very great and the breath is only at volume up. The sound of guitar is more loud than noise.