Jolida jd 100 owners

I think their function is as a shield, not as a damper. I've had a couple of vintage amps that use a single metal-can shield only on the input/"gain" tubes. Then again, most modern amps don't seem to bother.

Not sure if they're necessary in this case, as I doubt they're using those 12AX7 tubes for gain - though it seems an odd choice of tube type for a line-driver.

I believe the 12AX7s are in fact used for gain.
I left them on when I had a JD100

I took them off and use Herbie's Tube Dampers.

I took them off with know ill effects. The JD 100 didn't seem to have a major effect on the tubes as they tested new after years of use. (NOS Mullards instead of the stock) Never thought to use dampers.

Thanks for your responses so far. Since I have the addiction known as audiofoolism, i'm sure I will be rolling tubes soon. I was just wondering the advantage of the shields because they are one more thing to take off and put on.