Hihg frequencies were making my shit crackle

aen · Post by **aen** » Fri Apr 11, 2008 11:50 pm

Specifically the speakers on my twin reverb. Pretty much anything on an unwound string and the speakors would get to static-ing. I figure, well shit, I was going to get another cab anyway, but I better make sure it is the speakers.

So I plugged Robert Ogs cab into the twins output, and it sounded like a million bucks. I plugged the stock speakers back in, and they sounded like a million bucks.

WTF MATES? DO youall think it could have been a loose connection or something? or a loose toob that was pushed back in during the switch? I dont recall bumping any tubes...

My amp has been having on and off nights, where thursday it'll sound all shit and crackly on the hi freqs and then on sunday sound good.

Ninja Mike 808 · Post by **Ninja Mike 808** » Sat Apr 12, 2008 1:15 am

Did you inspect the speakers to see if maybe they were torn in places? Also, did you replace the tubes and not rebias the thing?

Post by **Doog** » Sat Apr 12, 2008 1:56 pm

Maybe time for new preamp tubes?

aen · Post by **aen** » Sat Apr 12, 2008 3:48 pm

Ninja Mike 808 wrote:Did you inspect the speakers to see if maybe they were torn in places? Also, did you replace the tubes and not rebias the thing?

The speakers were torn and then repaired. never replaced any tubes.

Y'all seem to be missing the second part. When I plugged the STOCK speakers back in, they sounded just fine.

Jesse · Post by **Jesse** » Sat Apr 12, 2008 4:36 pm

Yeah, it sounds like you had a loose connection originally.

filtercap · Post by **filtercap** » Sat Apr 12, 2008 11:54 pm

If it's an intermittent static-y sound, especially one that you hear on treble peaks, I'd suspect some dirty preamp tube pins and/or socket connectorszsz first. When I have that problem, it's usually there sometimes, gone sometimes, and then back again. There might also be more background noise when I'm not playing, that sounds like scratchy radio interference.

Cheap-and-easy fix, if it works: With the amp off, remove each preamp tube and swab each tube pin with some alcohol on a Q-tip or some cloth. Rubbing alcohol, not whiskey. If you really want to get into it, dip something pointy, non-conductive , and not too hard (like a bamboo skewer) into alcohol (isopropyl alcohol, not schnapps) and clean each connector in the tube socket also. Each connector is a pair of springy metal tabs that grip the tube pin. Clean between those tabs.

Hours later, having carefully cleaned 54 pins and another 54 holes, put the tubes back in, switch on, and rock. If you're in a hurry and you play the Vibrato channel, just do tubes 2, 4, and 6. (When looking into the back of the amp and counting from right-to-left.)

If you're in a real hurry, you may be able to temporarily fix the problem by just pulling and then plugging-in each tube. That might scrape any dirt aside so it doesn't interfere with the electrical connections.

mewithoutus · Post by **mewithoutus** » Sun Apr 13, 2008 12:06 am

SOLID advice filtercap.

aslo, with the amp ON and the stanby ON, CAREFULLY tap each tube with an eraser or something else kinda soft to see if theres any crackle or noises. if so, you may need to replace your tubes.

do what filtercap said first, that way you will know your shit is making good contact before you tap on teh tubezorz.