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previous: Dave R Thanks, Rick- that sounds really co... -- 5/26/2000 12:51 AM

Re: Ooooooo...

5/26/2000 12:58 AM
MBSetzer	Re: Ooooooo... At Home Depot they usually have clear plastic PVC tubing, like we use in the chemical lab. There is probably a large enough diameter for a glass 6SJ7GT, even more likely the slightly smaller ID tubing that would fit a metal preamp valve. This is thick-walled soft plastic and could be more effective than shrink-wrap. I guess it would depend on how hot you run your preamp whether the tubing could handle it or not. For dampening microphonics you would want to be able to fit the valve inside the plastic tube without any struggle. One of the most insidious injuries I remember from a chem lab was when a guy was trying to routinely put a tight rubber hose on the end of a glass tube. The glass snapped and the force of his hand gouged the sharp edge deep into the muscle between his thumb & index finger. He was a good fiddle player too, and wasn't able to do a thing for months. Also I had just looked again at my old '59 Epiphone Pacemaker when another poster asked about one. Turns out this old practice amp had original o-ring grommets in the holes that the 12AX7 socket was riveted to. This isolated the socket ring (& shield) from the chassis electrically and mechanically. They had soldered a ground wire to the rivet within the grommet in order to ground the metal shield when it was in place over the 12AX7. Nothing wrong with adding both types of isolation to see if it is enough or even helps. If you do change to a 12AX7, there is a ready-made adapter for reducing an octal hole to 9-pin mini. WeberVST is offering them now, you would want to make sure it will work with your bolt spacing. Hope this helps, Mike

5/26/2000 12:58 AM

MBSetzer

Re: Ooooooo...

At Home Depot they usually have clear plastic PVC tubing, like we use in the chemical lab. There is probably a large enough diameter for a glass 6SJ7GT, even more likely the slightly smaller ID tubing that would fit a metal preamp valve. This is thick-walled soft plastic and could be more effective than shrink-wrap.

I guess it would depend on how hot you run your preamp whether the tubing could handle it or not.

For dampening microphonics you would want to be able to fit the valve inside the plastic tube without any struggle. One of the most insidious injuries I remember from a chem lab was when a guy was trying to routinely put a tight rubber hose on the end of a glass tube. The glass snapped and the force of his hand gouged the sharp edge deep into the muscle between his thumb & index finger. He was a good fiddle player too, and wasn't able to do a thing for months.

Also I had just looked again at my old '59 Epiphone Pacemaker when another poster asked about one. Turns out this old practice amp had original o-ring grommets in the holes that the 12AX7 socket was riveted to. This isolated the socket ring (& shield) from the chassis electrically and mechanically. They had soldered a ground wire to the rivet within the grommet in order to ground the metal shield when it was in place over the 12AX7. Nothing wrong with adding both types of isolation to see if it is enough or even helps.

If you do change to a 12AX7, there is a ready-made adapter for reducing an octal hole to 9-pin mini. WeberVST is offering them now, you would want to make sure it will work with your bolt spacing.

Hope this helps,
Mike