Where to go next with the turntable

Is the bass adequate when using a digital source?

The reason I ask is that I had the opportunity to audition a couple of power amps in my main system. One was an older  Lexicon, another was a fairly expensive Chord, and I threw in an older Jeff Rowland I use for video.

Result?  None had the bass richness of my usual power amp, a Conrad Johnson Premier 11a from the 1990s.

Phono cartridges will also offer a range of bass reproduction but I'd suggest that before looking there, you first confirm whether any bass shortcomings might not be due to the amplification train.

wspohn, 
The bass is fine with digital. Hegel H390, 250wpc, Magnepan 3.7i and a pair of SVS SB-3000 subs. 
 

I'm pretty sure that was Linn that said not to clean records

@traudio It was Roy Gandy of Rega who said that. It was even printed in the Rega TT manual (don't know if it still is).

During a period of time where the idea of cleaning Vinyl was quite new, but the use of Cartridges was very popular, as well as being a potential product, that was as result of high volume sales creating the life blood of many Companies. It make total sense that a entity with a real interest in sales of a product that would have an extended life through the usage of cleaned Vinyl would be inclined to make the remark about not to clean Vinyl. 

Putting the period into a more focused context, well established Audio Companies were now sharing space at Commercial Exhibitions alongside the New Upstart Record Cleaning Device Companies.

Companies advising on Record Care could hardly use preserving the LP as a reason to spend on their products, as the Vinyl in nearly all cases was very cheap and very easily replaced. There are exceptions to this, as some Radio Stations may have had out of pressing Archive medium needed to be kept in Top Quality Condition.

New Incorporated Companies advising on Record Care were very direct in their descriptions to the general enquirers about getting the benefits of additional hours of usage from a Cartridge. Using the additional hours of usage from the expensive Cart's as the beneficial offset cost savings, which were able to be homed in on, to justify buying into record care devices.

Additionally, Record Care Companies new very very little about the importance of a Cleaning Solution being totally removable form the LP.

Where some solutions being promoted were very capable of leaving the Groove embedded with a new crud, that would have never been present unless deliberately contaminated through the new adopted cleaning methods.

Distilled Water and IPA were not only the bases of solutions, other additives have been encouraged as a 'word of mouth' reveal, or the under the counter (join out secret club) through this secretive products. 

For myself, I am certain, the PAVCR Guidance for a Cleaning Solution and the Manual Method has surpassed any previous used method and removed all old cleaning method solution residual substances from the LP's Groove.    

@traudio , 

You are entirely correct about the LP 12 being a PITA. The suspension is a terrible design. Please do not let that sour you on suspended turntables. They will have superior bass due to the absence of environmental rumble. Your subs will like it also. A system Like yours deserves at least a Sota Sapphire. You can set a bomb off in front of a Sapphire and nothing will happen, even if it is sitting on a folding table! David Fletcher pioneered the design now used by Basis, SME and Avid. The chassis is hanging from the springs instead of sitting on them, a much more stable approach. I am extremely familiar with 3.7s. I have set up a bunch of them. Good for you using subwoofers. If you are looking for more punch and more forward bass. The Clearaudio Charisma will do it. You can also work with your subwoofers. Chances are you are using the low pass filters in the subs?? If so that is an AWFUL thing to do, much worse than not cleaning your records. The 3.7s benefit from removing at least 80 Hz and under from them. The problem of matching subwoofer is impossible to do well by analog means. It is impossible to get the timing and phase perfect by ear. I should know. I tried doing that for 15 years starting in 1979. You need digital bass management. With it you can make your bass sound however YOU want. The best way to do it is with a digital preamp like the MiniDSP SHD or Studio with outboard DACs (Benchmark uses that approach), The Anthem STR, the Trinnov Amethyst and my favorite the DEQX Pre 4. The Pre 4 will not be available for about 6 months. It's big brother the Pre 8 is being released just now. The only difference is the Pre 8 has a full 4 way crossover in it. You could tri amp the 3.7s and run your subs. It is about 3 K more dear. You subs you would cross at 80 hz 8th order (48dB/oct). You could actually push it to 100 Hz without getting the subs into the midrange. You will get another 6 dB of headroom, a cleaner midrange and the improvement in bass WILL blow your mind.

Having said all this, you will still benefit from an improved record playing device. If it were me with your system I would get a Sota Sapphire and put a Kuzma 4 Point 9 on it. I would use the Clearaudio Charisma or if you should go the route of the digital preamp the Soundsmith Voice.