Amp doesn't react. What could happen?

[Miritalner]

Hello, I'm new here and I'm also a complete novice to bass playing, so maybe my question would seem stupid.
But the case is, today I turn on my practice amp and I hear that low continuous sound. No reaction to anything that I do with my bass. The amp just sits there and keeps humming the note so well that any singer would be jealous.
What could go wrong? Could it be that I stuffed it up by pulling the connection cable out of socket while the amp was turned on? It happened once I didn't realize I walked off too far away playing my bass and the cable popped out. Apart from that, I didn't even touch it that often except the on/off switch.

 

[oddio]

It's going to be difficult to tell what's wrong without a bit more information. It could be something as simple as a bad cable or just time to replace the battery in your bass (if it uses one). If you know the make/model of the amp that might be useful.

 

[Miritalner]

No, my bass works without battery.
Hmm, it looks like the model is NOTHING. It just says BA20 on it, meaning it is a Bass Amplifier with 20 Watts of loudness. I got it from e-bay in one of those starter packs. Maybe I should contact the seller and ask them since I got the warranty. But I just want to find out what could possibly go wrong.

 

[steveksux]

Rule #1 Always start with the cheap stuff when you're troubleshooting and don't know what the problem is. Good advice when you start swapping stuff out to see what the problem is.

Is that a low note its "singing"? Does it do it with the cord unplugged?

If it only does that with the cord and bass unplugged, it would be the amp, but might just be a loose wire on the input jack.

If it only does it when the bass/cord is plugged in, try a new cord. Borrow another guitar and try that. It could be the bass too.

Try plugging just the cord in, holding the rubber part of the cord, then touching the tip of the cord. If the amp reacts to that, more than likely its something in the bass causing it.

Randy

 

[Miritalner]

Yep, it sings a low note, and does so no matter what I tried to do, with or without chord, with the bass connected or without it, with me touching the other end of the chord as well. The only thing that makes it shut up seems to be the insertion of chord into the phones jack, but this is not really a right place to connect the bass to, as the amp obviously does nothing but keeps silent.

 

[i_got_a_mohawk]

I wouldnt put too much faith in those cheap started ones, its probably just died to be a dick

 

[Miritalner]

Well, everything is pretty much clear now. It's either the chord or the amp, both from the same seller. Time to claim my rights. Thank you all for the help!

 

[tadawson]

Not to be a smartass, but perhaps if you used a CORD, instead of a chord (which does not carry electricity!) it might work better . . . . .

- Tim

 

[Miritalner]

Yep, I think you got a point there...

 

[Hollow Man]

Sounds like somewhere in your amp's signal chain, something's come loose. Bad input jack on your amp perhaps? Try the new cable idea, but if that fails, it's something in your amp. If that's the case, you don't have what it takes to fix it yourself, so you're better off taking it to a local repair shop.

 

[Miritalner]

I am inclined towards the "loosened jack" version, as I always expect the worse from unfamilliar gear. What would I need to fix it myself? Should I just take it apart and see what's inside? A loosened input jack doesn't sound like something that may cause me to stuff up the whole amp, does it?

 

[tadawson]

While a loose jack is typically not that hard to repair, we have no idea of your skill set, IE soldering ability, etc. I have known folks that could screw up a rock if they looked at it funny, and others that could do just fine, so you will need to make your own assessment of your skills.

If the jack is mounted to the face plate, and connected to the internals of the amp with wires, it's pretty simple.

If the jack is mounted to a PC board in the amp, then a mistake could get REALLY $pendy . . . .

And keep in mind, that there isn't much to "repair" on a 1/4" jack, unless a wire came off. Normally, they are just replaced . . . .

Lastly, if you still get the hum with the volume control turned down, I can tell you for a fact, it's not the jack . . . . . it is most likely the power supply in that case . . . . .

- Tim

 

[Miritalner]

You got it right on-target, as fencers say. The evil piece of machinery hums even when I turn the volume to zero. So it is the power supply then? Hmm... things get even more interesting.

 

[tadawson]

I can't guarantee you that it is the power supply, but a failed filter capacitor letting AC ripple into the main power feed to the amp is a very common source of the problem that you are seeing, although there are other things that can do it. As I said before, what I CAN tell you is it isn't the input jack . . . . . any hum introduced there would be controlled by the volume controls . . . .

- Tim

 

[Miritalner]

All right, but then anyway, I'm sending it back to where it came from. Not that you really need an amp for your technique practice (at the moment, the only thing I'm concerned with), so I'll just get the seller to replace this little bastard with a new one.