Ringing noise from cab.

[GuitarGod87]

I have a Randall RS412XLT100. I'm playing through right now and I've never noticed it, but when I stop playing there's metallic ring after I stop the note. Almost a reverb metallic sound. It does have the metal grill over the cloth. Does anyone else hear this on your own randall cab with the metal grill? Is it the metal grill? Hope to get some responses back about this. I'm really not happy about it.

Thanks

 

[6stringgrind]

Just guessing, but it sounds like something's loose. Does it have a removable back panel? I had to take the panel off my 2X12 cab because it vibrated.

 

[GuitarGod87]

it does have a back panel. I called a local amp shop that's pretty reputable and they said it sounds like a micro phonic tube. So I'm going to try to switch out the preamp tubes and if that doesn't work then I'll prob send it in to them.

 

[nomad100]

sounds like a bad tube to me as well, possibly bad power amp tube even

 

[bruce egnater]

I assume the head is on top of the cabinet? If so, set it on the floor at least a few feet away from (and not directly in front of) the cabinet and recheck. Report back. This will help identify if it is the cabinet or the amp.

 

[GuitarGod87]

I read on mesa boogie's site that it might be a bad power tube. They said to tap the tubes while the amp is plugged in and on. I got the same reverb sound from tapping two of the power tubes. They were also burnt looking compared to the other two. Bruce, I'll swap the tubes and check if it's still making the noise. If it is, I'll try your advice. Thanks everyone.

 

[Hamner1]

Microphonic Power tube.
http://www.youtube.com/watch?v=NAF42EwLzks&feature=related


Microphonic Preamp tube.
http://www.youtube.com/watch?v=QM2qWZYbInI&feature=related

 

[GuitarGod87]

well I tried several guitars and a different cabinet, the noise varies for each guitar. I played through a Bc Rich V with EMGs, a Ibanez JS100, Ibanez RG420, and a Ibanez RG370dx. I got the noise the most from the 370. I swapped out the power tubes and preamp tubes, not with new ones though and I still had the same noise.

@ bruce, I took the head off of the cab and it still made the noise.

From what I saw in the vids posted, I do hear a noise from the power tubes when I tap them, so that's a obvious factor and they definitely need to be switched out. The preamp tubes sound fine when I tap them. The noise only lasts for about half a second after I quit playing. I'm going to make a video with my lapttop right now and try to post on youtube. It may or may not pick up the sound since I'm most likely going to use the built in mic.

 

[GuitarGod87]

Here's the link to the video on youtube. The lighting is terrible btw. It's sunset and I don't have many lamps in the living room, lol.

http://www.youtube.com/watch?v=t5mb8DGJmnU

 

[GuitarGod87]

BUMP! any solutions or ideas?

 

[nomad100]

If it's not a tube or the cab maybe take amp into be repaired. Could it be a cable or stomp box I have one tuner that will ring sometimes.

 

[KillTone]

Sounds like your tremolo springs.

 

[Hamner1]

Do you have a different cab to test the head through? If you get the same issue than it is likely the head. If no other cab take the head to the music store or friends house & try the head through their cab.

 

[KillTone]

It is the tremolo springs. Put something in the cavity to dampen the springs and see if it helps. For a temporary "fix" just to check it, cram a cloth in there.

There was a thread about this a LOOOONG time ago. A few members mentioned that they use a section of rubber hose from a lawnmower fuel line to "jacket" the springs. They all said it works great

 

[nomad100]

Or just remove the stupid thing?

 

[GuitarGod87]

yea, thanks for the suggestions. I have tried it on a different cab and it still makes the same noise. it's not as loud as it is in the video, extremely poor audio. I've tried different guitars too and no luck. Are power tubes suppose to make a noise when tapped? I know preamp tubes are. btw, dampening the springs didn't work...

 

[m0jo]

This doesn't sound like a microphonic tube to me, sounds exactly like a tremolo spring. Then again, that is never that loud ..

But because you say it's different on different guitars and they are all tremolo-loaded, I'd definitly check this out more.

I've had good results with pulling some foam into the springs, there are different solutions like the rubber tube as well.
How did you dampen them?

 

[GuitarGod87]

I've already tried dampening the springs and I'm still getting the noise. I'm going to have to take it in. I can't figure out what's wrong with it.

 

[kc2eeb]

Do your pick ups have metal covers?
That sound is from the guitar. The truss rod can ring like that. Tap the back of the neck.
Tap the pick ups with the plastic end of a ball point pen.
It could be the pick up height adjustment springs.
Tap all around the guitar with your knuckle.

 

[GuitarGod87]

I've tried different guitars on it too. I did adjust the truss rod recently, that could be it. I'll try tapping the guitar tomorrow when I have more time. What kind of sound should I be looking for?