What's your budget? My VAC tubed preamp has excellent low bass extension 8500.00 new and 4300.00 used, my Manley Shrimp 1800.00 new, has a full punchy bass but does not have the weight or extension of the VAC. I had an Audio Research LS15 which was decidedly light weight in the bass in both fullness and extension. I would venture that a solid state preamp is going to be your best choice unless you spend big bucks and even then you will likely get more thump from solid state if that's what you are looking for.
I owned a BAT VK-30 tubed preamp and home demoed a few others thanks to great dealers nearby. I always felt the best part of the electronica genre was missing-the leading edge of bass transients. When I went back to a SS preamp BAT-VK-40, and then my standby Rotel RC-1090 my wife asked how it was working out and my answer was "bass is back!" The tubed preamps did lots of other things well but ultimately for me using a SS preamp was the most satisfying overall sound. Crystal Method, Underworld, Aphex Twin, etc just didn't have the impact with the tubes. If I had two hifi rooms I would have tubes in one and SS in the other. The tubed room would be the pinky-up wine, tea, classical, jazz, and sophistication room. The SS room would be coffee, beer, tequila, rock and electronica belching out loud room. Right now it's all happily coexisting.
I'd say my target budget is around $1500, and I definitely want to stay below $2k.
For me, part of the experience with this kind of music is being able to feel the music, which you can definitely do with SS equipment even if your system isn't running hot in the low end of the frequency domain. If I can't get this from a tubed preamp in my price range, I'll have to go with SS.
I would look for a used BAT preamp. I've heard many different tube preamps and IMHO BAT offers not just the best bass performance in a tube preamp, but one of the best bass performaces from any type of preamp period, tube or solid state. You should be able to get a VK-3iX in your price range.
Your question is of interest to me as well.
From my experience with BAT, Aesthetix and CAT line stages, the CAT really excels at the frequency extremes. Incredible bass extension and authority.
BAT, either tubed or SS will give you good, solid, bass.
A more general answer - When Joule Electra was first introduced, they offered the LA-75 and LA-100 line stage. The difference was the LA-75 had a SS power supply so was less expensive. The main sonic difference was a stronger, more dominant mid-bass with the 75. Those of us who heard the comparison agreed the LA-75 would appeal more to someone listening to rock, reggae, etc.
So one consideration could be to audition pre/line amps with SS front ends, rather than all tube designs.
Also, you suggest you listen to a "decent amount of material in the 20 Hz - 40 Hz range". Unless there is dominant electronic instrumentation, that might not be likely. The open E string on a bass is 42 Hz. How much do you actually hear below that? Most folks are not aware of the real frequencies of the music we listen to. Have you heard a 60 cycle hum from a ground loop or other problem? That's pretty low and many speakers do not produce much below that, yet sound like they produce strong bass.
Anyway, good luck and happy listening.
I listen to a lot of stuff with information below 42Hz! I played string bass in junior high and past college. So I find that bass response is important to me to be convincing, and since I like a lot of electronia, I have speakers that go to 20Hz and electronics to match.
In tinkering with a lot of tube preamps over the last 40 years, I found that the big problem in getting tube preamps to play bass is the output coupling cap. You can make it bigger to get bass, but if you do so you can loose detail as the bigger caps are less musical. So I started tinkering with direct-coupled outputs on the preamp, inspired by an old Berning preamp called the TF-10 (which also had a direct-coupled output). It was a bit of a trick but I got it to work.
Not only do you get deeper bass with a direct-coupled output, you also get more mid and high frequency detail without fatigue- its sort of the best of both worlds.
So- tube preamps thus have the ability to better than the best transistors, IOW deep bass is not an inherent limitation with tubes; it has to do with the coupling caps.
Well, that explains why the VAC Renaissance has superior bass compared to other preamps I've used. It has no coupling capacitors in the signal path. That said, I don't think Rrolack will find an Atmasphere or VAC Ren for under 2K.
IMHO, tube preamps are good for all types of music. I listen to various styles including jazz, blues, dixieland and heavy metal. A good tube preamp will reproduce the full spectrum of audio. The reason many solid state AMPLIFERS do better bass than tube AMPLIFIERS is because almost all tube amplifiers use output transformers and they can be the limiting factor for bass. Tube preamplifiers on the other hand do NOT usually have output transformers since they drive high impedance loads.