'Shred' and Squeal

I know the manual suggests that using shred mode at higher gain levels and/or with prsence/treble dialed higher can lead to tube squeal.

I am having this happen on a new jp-2c and am a little surprised how quickly it starts to squeal (i had thought the warning was more intended to tell you not to dime those knobs).

Im curious for those that use Shred, where are your gain (pushed/pulled), presence and treble set when this starts to happen on your amp? What about the volume knob?

Thanks!

The guys that I play with, https://flic.kr/p/Qh8Tu9 suggested that the band should add "man in the box" and "enter sandman" to the list. I use ch.3 with the treble at noon and the gain pulled at 2 pm, presence at 2, not pulled and the shred on. Tom Anderson H3+ pick up. Rip roaring tone, no squealing. I've seen some videos where the treble and presence are dimed, I haven't tried that yet.

I use shred to shore up the mids and treble for low volume playing. The volume level also effects the feedback as well. Definitely drop the presence some, especially if you pull it. You may also need to adjust the sliders on the 5 band EQ to compensate.

If it seems problematic, do you have similar sensitivity when not using shred ? I had a hyper active preamp tube that was on the edge of going microphonic (V1) but took me a while to discover it was just V1 as I had similar issues with a different tube in V1. Decided to change all of the preamp tubes with some slightly new Mesa tubes I had on hand.

I turn the treble knob back to about 1:30 when I enable shred (at modest volumes), and that helps for me. FWIW. At high volumes I figure the pickups should be facing the crowd, not the amp.