Hi All,
I just bought a used Lonestar Classic. Love the amp so far
8) except that I
really haven't had a chance to tweak it to my liking .
One thing that concerns me is, I am getting a high pitched noise from it.
the symptoms are as follows:
happens only with the drive channel (loop engaged)
happens without an instrument plugged in.
increases as the drive knob (and the output knob) is turned up
Also is (very) minimal when the drive toggle switch is set to 'normal' but if I try to use either 'thick' or thicker' it becomes more pronounced.
seems to completely go away when I switch the fan off
Thought I might have a monophonic 12ax7 (the one by the fan) so I swapped it (with a used one I had laying around from my F30) - it seems to have diminished but is still there.
I tapped each of the pre amp tubes lightly with a pencil but cant seem to find a blatant 'bad' tube although the tapping can be heard through the amp and speaker on some tubes more than others.
Also I tapped the fromt face of the amp (the chasis I suppose) and I can hear a metallic amplified noise through the speaker.
I guess a set of tubes would be the first move ?
but what about the fan ?
has anyone else experienced this ?? Could it be that the fan is noisy and being amplified somehow through the circuit?
Don't know how to proceed - any advice is extremely welcome.
please don't suggest using 'hard bypass' I really like the distortion channel sound.
ps
called mesa before I did all this troubleshooting like tapping tubes, switching the fan off and on, and swapping the 12ax7 out etc, and the customer service rep seemed to think that it was a bad tube (yes, the one by the fan)
Thanks in advance boogie men!
Zeemo
I just bought a used Lonestar Classic. Love the amp so far
8) except that I
really haven't had a chance to tweak it to my liking .
One thing that concerns me is, I am getting a high pitched noise from it.
the symptoms are as follows:
happens only with the drive channel (loop engaged)
happens without an instrument plugged in.
increases as the drive knob (and the output knob) is turned up
Also is (very) minimal when the drive toggle switch is set to 'normal' but if I try to use either 'thick' or thicker' it becomes more pronounced.
seems to completely go away when I switch the fan off
Thought I might have a monophonic 12ax7 (the one by the fan) so I swapped it (with a used one I had laying around from my F30) - it seems to have diminished but is still there.
I tapped each of the pre amp tubes lightly with a pencil but cant seem to find a blatant 'bad' tube although the tapping can be heard through the amp and speaker on some tubes more than others.
Also I tapped the fromt face of the amp (the chasis I suppose) and I can hear a metallic amplified noise through the speaker.
I guess a set of tubes would be the first move ?
but what about the fan ?
has anyone else experienced this ?? Could it be that the fan is noisy and being amplified somehow through the circuit?
Don't know how to proceed - any advice is extremely welcome.
please don't suggest using 'hard bypass' I really like the distortion channel sound.
ps
called mesa before I did all this troubleshooting like tapping tubes, switching the fan off and on, and swapping the 12ax7 out etc, and the customer service rep seemed to think that it was a bad tube (yes, the one by the fan)
Thanks in advance boogie men!
Zeemo