FWIW, I've bought a lot of different DI's for recording Bass.
- Reddi
- U5
- BDDI
- RBI
- RPM
- Bass Pod
- Pod HD500
- Bass V-Amp Pro
- B3
Out of those units, only two remain.
The Avalon U5 and the Zoom B3.
I wanted to like the Reddi... as many folks absolutely rave about it.
Perhaps mine was defective, but (to me) it didn't sound anything like a B15.
My unit was a little prone to noise. Especially bad when used with a Ric 4003 that was poorly shielded.
The SansAmp units all had a nice "grind"... but the dynamics were a bit too squashed.
The BDDI and RBI have a tendency to sound pretty "clacky" emphasizing the upper mids.
The RPM has a ton of gain on hand. You can get crazy with the distortion.
You can quickly get decent sounding bass with any of the SansAmp units.
Although super convenient and low cost, the SansAmp units (IMO) produced pretty decent but not great results.
The POD units are certainly convenient and low cost.
Many of the amp/cab combinations sound muffled or lack articulation (especially the Bass POD). Woof!
Granted, there's not a lot of top-end in a mic'd bass cab, but there's still definition/articulation.
The POD HD500's Ampeg model was IMO the best of the bunch.
I'd opt for SanAmp units over the POD range.
The Avalon U5 is built like a tank.
The sound is what you'd expect.
Clean, clear... and a little "larger" sound than using a Radial DI. Guess you could describe it as "hi fi"
I don't use the onboard "tone shaping" preset EQ settings.
The U5 lets the character of the bass come thru. It's enhanced slightly (similar to using a Neve preamp - larger but the basic tone isn't changed). The U5 won't produce an "amped up" Ampeg type of sound.
The cost of the U5 is below the Reddi... and a bit more than the rest.
If you're going to use AmpSim plugins, IMO the U5 is your best DI option.
Of all the Amp Modeling units that I've owned, the inexpensive Zoom B3 is by far my favorite.
I've mentioned this before, but there's a Bassman 300 model in there that's absolutely fantastic.
I owned a SVT Classic (80-lb head) strickly for recording. Using the Zoom and tweaking that Bassman 300 model, I compared results side-by-side with the SVT Classic/mic'd cab. The Bassman 300 model yields results that sound so good... I decided to sell the SVT. You can get a little dirt/grind... and the tone is balanced, full, articulate.
I'm into classic-rock bass tone... and this is it.
For a low cost Bass recording option, you can't beat the Zoom B3