There's a lot of DI's out there, from simple to complex, passive or active, cheap to expensive. I'll suggest 3:
1. Behringer BDI 21, it's very cheap and simple with a clean tone. Some folks say it's a carbon copy of the Sansamp BDDI, but not me, it's pretty clean unless you crank the gain knob to 10. Not bad for $25 new or $15 used.
2. ART USB Dual Tube Pre, it's only $99 brand new, has a real 12AX7 tube in it, it can be used as a usb audio interface as well, has a built in limiter and other bells and whistles. Lots of folks here swear by this one.
3. EDEN WTDI pedal, great tone, $99 used, I don't own it and never used it but folks here have raved over it. Do a search in the AMP forum and you'll find them.
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