How do I get a speaker with the bass slam of my el cheapo ear buds...?

What speakers in your stereo system?
i think you have never heard a good stereo system if you think bass performance from a earbud is impressive. Yes the earbud can go low and loud but it is nothing like true bass from an actual woofer of substantial size in an appropriately tuned cabinet and volume 

Headphones can have bass slam, but it doesn't compare to the sound quality or sensory impact of sound waves interacting with your entire body.

My high end headphones and headphone amp don't come close to producing the slam and impact of my Legacy Audio Focus 20/20 speakers (or any of the smaller systems I have set up in my house). 

There's no comparison between a driver that would fit in an earbud and a large woofer(s) and/or subwoofers.

Dear d2girls, you are not logically wrong.  However,  I would be very glad if you can provide some good doable suggestions on how to improve the sound from a phone output.  Happy Friday every one!

The slam you get from the ear buds is because being in the ear canal they only need to move a very tiny volume of air. Much less than 1 cc I would think. The speakers you're using have to fill a volume millions of times greater.

Those ear buds by the way are crap. You're right, they boost the bass response. Ear buds that sit in the ear without making a tight seal around the ear canal are losing bass out the cracks, so to speak. Plus being free they are pure crap. So they boost the bass to warm up the sound hiding the fact they are awful in pleasing warm exaggerated bass. 

What you want are some good IECs, Inner Ear Canal phones. The Shure SE-535 is a good solid bet and will blow away any ear bud with much deeper, flatter and more accurate bass, beautiful midrange, excellent grain free extension and incredibly more lifelike dynamics. 

@ d2girls
My front L/R speakers are Legacy Audio Signature II from the 1990s.