acoutic amp making lots of static noise

[Sonu]

Hi Guys,

I recently bought a fender acoustasonic 30 watt acoustic amp and was
working fine till a few days ago. Now when I turn it on it makes lots
of static noise (kinda like when a radio gets no signal). This happens
even if the guitar cable isn't plugged into it.

I tried turning off my computer (abt 15 feet away) and other
electronic stuff also but doesn't make a difference.

It is virtually unusable at this point.

I would appreciate any suggestions or solutions as I'm utterly
clueless and this is my first amp.

The only thing that has changed in my home recently is that I have
bought a new computer (if that makes a difference).

Thanks in advance.

Sonu

[Dan Carey]

Post by Sonu
Hi Guys,
I recently bought a fender acoustasonic 30 watt acoustic amp and was
working fine till a few days ago. Now when I turn it on it makes lots
of static noise (kinda like when a radio gets no signal). This happens
even if the guitar cable isn't plugged into it.
I tried turning off my computer (abt 15 feet away) and other
electronic stuff also but doesn't make a difference.
It is virtually unusable at this point.
I would appreciate any suggestions or solutions as I'm utterly
clueless and this is my first amp.
The only thing that has changed in my home recently is that I have
bought a new computer (if that makes a difference).
Thanks in advance.
Sonu

How recently? Is it still under warranty? It sounds like you've got a bad
bandpass transistor (in the treble or base circuit). Should be an easy fix
for a good tech if it's not under warranty.

Geezer

[Chuck Boyer]

Sonu,

I don't know that amp, but here are some general suggestions based on my dated
experience (and EE training ;) -

First, I would be surprised if the new computer had anything to do with the
problem. And if the amp is still under warranty I'd take it back for repair or
replacement.

Otherwise:

Problems with electronic gear can often be traced to a failed connection, e.g. a
loose wire, a broken printed circuit trace or a cold solder joint. If you can
affect the noise by (gently) smacking the amp, your problems may well stem from
a bad connection; I'd be inclined to suspect a faulty signal ground.

Is the noise level affected by the volume control setting? If so, then the noise
is being generated before the volume control, perhaps from a bad input jack
connection. Otherwise, there's something wrong later in the circuitry.

Apart from the noise, can you still hear the guitar through the speaker? If
not, then something in the electronics has failed catastrophically. It's pretty
hard to give specific suggestions, though; you'd need to inject / trace a signal
through the circuit to identify the point of failure. To complicate matters, the
presence of DSP in the hardware can make it difficult to correlate a symptom
with a specific point of failure in the amp.

Good luck!

- Chuck

[Sonu]

I bought the amp just 2 months ago from Guitar Center so it would be
under warranty. I'm going to take it back to them.
More about the symptoms. Yes I can hear the guitar sound when I plug
into it but the static noise (GHRRRRRRRRRRRRROOOOOOOOOOO) is so loud
that it spoils
everything.
The static noise becomes louder as I increase the volume.
I've tried to plug it into different power jacks in the home, but
problem persists.
Thanks for your suggestions, guys, I'm going to go ask the Guitar
Center abt what's going on.

Post by Chuck Boyer
Sonu,
I don't know that amp, but here are some general suggestions based on my dated
experience (and EE training ;) -
First, I would be surprised if the new computer had anything to do with the
problem. And if the amp is still under warranty I'd take it back for repair or
replacement.
Problems with electronic gear can often be traced to a failed connection, e.g. a
loose wire, a broken printed circuit trace or a cold solder joint. If you can
affect the noise by (gently) smacking the amp, your problems may well stem from
a bad connection; I'd be inclined to suspect a faulty signal ground.
Is the noise level affected by the volume control setting? If so, then the noise
is being generated before the volume control, perhaps from a bad input jack
connection. Otherwise, there's something wrong later in the circuitry.
Apart from the noise, can you still hear the guitar through the speaker? If
not, then something in the electronics has failed catastrophically. It's pretty
hard to give specific suggestions, though; you'd need to inject / trace a signal
through the circuit to identify the point of failure. To complicate matters, the
presence of DSP in the hardware can make it difficult to correlate a symptom
with a specific point of failure in the amp.
Good luck!
- Chuck

[Lee D]

Post by Sonu
Hi Guys,
I recently bought a fender acoustasonic 30 watt acoustic amp and was
working fine till a few days ago. Now when I turn it on it makes lots
of static noise (kinda like when a radio gets no signal). This happens
even if the guitar cable isn't plugged into it.
I tried turning off my computer (abt 15 feet away) and other
electronic stuff also but doesn't make a difference.
It is virtually unusable at this point.
I would appreciate any suggestions or solutions as I'm utterly
clueless and this is my first amp.
The only thing that has changed in my home recently is that I have
bought a new computer (if that makes a difference).
Thanks in advance.
Sonu

I remember somone having a problem like that and saying that it was the
spring reverb unit. I never messed with it (like that would have really
helped), so I couldn't tell you if it was true.

Lee D