I'm here.......
The T-verb is a great amp, period :!:
It all depends on what you definiton of "shred" is?? It also depends on your guitar?? With a hot humbucker guitar, You can get some real fluid, saturated tones from it in the Vintage mode that are great for soloing and shred. You can even back off the gain a bit, or not, and use a Tubescreamer with it to give you more saturation.
As far as a tight bottom, the T-verb is essentially a Dual Rectifier (with reverb and tremolo) and can thump but has that famous Rectifier low end mush (for lack of better words). I say mush in a loving way, chords sound amazing as do the leads, but a tight rhythm gets a little flabby. EL34 will help tighten up the bottom end some, but it still sounds like a rectifier.
For a high gain amp, the T-verb has a great clean tone and does low to med gain very well too. After the Road King, the T-verb is my favorite Boogie and I'd love to have anothre one someday..... and just very well may :wink:
In the mean time, if you wanna hear some recto clips.... you can hear a few on my little guitar site at www.guitartest.moonfruit.com , just go to the Road King clips and give the top clip a listen. That's all Dual Rectifier in the Vintage mode using 6L6's at a fairly low volume. The rest of the clips are RK exclusives.