What is the most dramatic way of increasing a speaker's Bass and Low mid?

Thanks! BTW loving the sound now after upgrading Amps, Preamp, and cables!

The simplest way for bass boost is use your room boundaries.  Using the example of a flat response bookshelf on stand in the middle of a room away from all boundaries, move that stand mounted speaker fully against one wall- this adds +3dB in low end boost.  Then step 2 is move fully into the corner  (2 boundaries) = +6dB bass boost.  Then step 3 is of course 3 boundaries, or the corner on the floor or the ceiling= +9dB in bass boost.  Speaker will sound awful but that is the impact of a corner on a speaker.  

If you do not fully push the speaker against a boundaries, there is still increasing bass response as you get closer and closer.  A good flat speaker will sound very tubby in a corner "area" compared to the middle of the room far away from boundaries. 

Quite often boundaries are the biggest reason why a speaker does not sound good in space. Being aware of the impact boundaries cause on speakers can be helpful.  

(And we haven't even mentioned reflections from boundaries!)    

Brad
Lone Mountain Audio (consumer)
TransAudio Group Inc (pro)
Pro and Consumer Audio Importers

Have you considered doing tests using room eq wizard first

BTW, if doing testing be wary of relying on the mic built into your phone, as they are focused on picking up midrange and won't pick up low frequency with any accuracy. 

Any simple test tone cd and a decent mic will have you on your way to measure the impact of some of the changes suggested(e.g. moving towards the boundary). Cheers,
Spencer

You can see what the problems are with a computer, USB Mic, and Room EQ Wizard. I think your suspicions may be correct and you have room nodes. You’ll need a few subs and can use Multi Sub Optimizer to crank out some new crossovers that will correct the suckout. A Mini DSP can be your active crossover to add the filters. Much less effective is to move the subs around the room and try that way but filters add delay, gain, up to 12 biquads. I have added SVS isolation footers on all the subs so that their vibrations don’t excite the room. They work really well. You’ll be really surprised what a difference it will make.