#1
Hi everyone. I had a thread earlier about upgrading my amps on, which I still plan on doing hopefully soon. However, I noticed on my current amp, a Vox VT15 there is a rattling sound coming out of the speaker. At first I thought it was the grill rattling but when I touch the grill it's not vibrating or loose. It sounds like it's coming through the speaker. I only hear it when I'm playing at bedroom volumes (but I guess that doesn't mean it's not there when I play louder). Any ideas?
#2
I should have added that it only does it when a note is being played. Other than that it is silent. But it rattles the whole duration of a note.
#3
If you used it a lot, maybe it's time to change the preamp tubes inside it.
#4
Thanks. I'll give it a try. Would there be any other symptoms of the tube needing to be replaced? I have also noticed that on certain settings the tone seems to "flutter", almost sounds like tremolo is on.
#5
First, loosen the bolts on the speaker and then tighten them up again. It might just be rattling. Then have a friend press on the speaker baffle while you play and see if that stops the noise—the baffle may have come loose and need to be glued down.

It is possible that the preamp tube is rattling. You could just try buying a new 12AX7 (most guitar stores stock them) and swapping them, assuming that the design of the amp makes it possible to get inside. I have no idea if these amps are serviceable.
#6
Quote by jpnyc
First, loosen the bolts on the speaker and then tighten them up again. It might just be rattling. Then have a friend press on the speaker baffle while you play and see if that stops the noise—the baffle may have come loose and need to be glued down.

It is possible that the preamp tube is rattling. You could just try buying a new 12AX7 (most guitar stores stock them) and swapping them, assuming that the design of the amp makes it possible to get inside. I have no idea if these amps are serviceable.

Yeah, its serviceable, although at least with the VT30, a bit of a PITA to get the tube in/out.
The VT50 is a piece of cake, so I dunno about the VT15, although I think it may use the same PCB as the VT30.

I'm gong for a loose speaker, but a loose tube is possible.
Definitely sounds as though something is loose.
Last edited by CodeMonk at Aug 26, 2015,
#7
Anything loose in the preamp section generally sounds more like a thump than a rattle by the time it reaches the speaker. Plus, you'd hear it more clearly, not less, with the volume up. This sounds like a loose component. Taking everything apart and putting it back together again snugly often fixes this sort of gremlin.

Having the amp completely apart also lets you find all the picks or tiny screws that seem to find their way into chasses occasionally.
#8
Last night I turned the amp on to better locate the sound but it wasn't doing it anymore. I turned it on a little later and then it was doing it. It was pretty late so I didn't start taking it apart. But after listening more closely it sounds more like a static hissing noise than a rattle. But again, I only hear it when a note is being played. It's silent when i'm not playing.
#9
Sound like a bad tube. I have replaced the tube in my Vox VT30 (I own two) and while it's a little time consuming it is not difficult at all.
Yes I am guitarded also, nice to meet you.
#10
I saw a Youtube video of a guy changing the tube in a VT30. I'm assuming the VT15 will come apart very similar to that.
#11
After some experimenting, the hiss is coming from my pedal chain. The noise gate on the VT15 was blocking the sound until I strummed a note. But when I turned off the noise gate it was constant. When I plugged my guitar directly into the amp it was silent. So now it looks like I have a new problem to look into.