"Slam"--what is it, is it really accurate?

I put this question under speakers because I assume "slam" is mostly a function of the speakers, but perhaps a certain level of amplification is required. The only places I have experienced slam is listening to certain demos at audio shops, and some live music. Most speaker demos I have heard over the years did not produce slam.

So, what mostly accounts for a system producing that "slam" you can feel in your chest? Is it that certain speakers are "voiced" with a mid-bass hump that causes it? Do they EQ the signal to produce it? Do they employ super powerful amps?

Secondly, how accurate is slam? How much of a goal in speaker selection should the ability to produce slam be?

The reason for the questions is that I am getting close to being in the market for new main speakers. My current amp is a McCormack DNA 1, BTW. Thanks for any info!

Slam can startle and slam can be subtle. It doesn't take much for certain notes to energize a room so it's not all in the purview of bass notes and loudness (volume). It's only because bass and loudness have been the topic of many a discussion when it comes to slam that that is what most folk think of when it's mentioned.

Having said that, I believe it's the speaker that delivers the goods.

All the best,
Alright, so maybe we're talking about different things when it comes to slam. For me, it's about when a solid bass note comes out of nowhere and you can both hear and feel it in a gutteral way. In my experience, it takes removing room resonance, electronic overhang, and noise out of the equation for those bass frequencies to be fully resolved and to have the fullest aesthetic impact. However, I also acknowledge that you can get there by leveraging uneven bass response in speakers, untreated room loading, and other "inaccurate" characteristics to make bass kick pretty hard. But in this case, you'll be trading in many other important aspects of the sound in order to maximize that bass impact.

Like others have mentioned, speaker design will play a big part. Ported speakers in general will "bump" more than other designs due to the resonant frequency of the port emphasizing at that frequency. It's not a completely even response, but it does give you that sense of drive and bass dynamics. That can be pretty fun if done well.
It's the room before the rest. Then it is the proper pairing of speakers and amp.

Case in point, when I first moved into my room, my system sounded fine but the bass response was not very good. I added treatments installed a proper rack dialed in the speaker position and then voila, Slam!

My system is nothing outrageous but I think that I am fortunate to have found a good synergy between all my components.

My slam test reference recording is the overture to Verdi's Rigoletto, the London Symphony Orchestra with Bonynge conducting, London FFRR OSA13105.
I don't believe "slam" can be accurate unless you have the very best components and a very tweaked(professionally) listening room. Even with great speakers that i've heard several times... IRS-Omega/KEF 207 I felt the "slam" was compacted and slightly over exaggerated when compared to live music? Maybe a super system with Wilson Grand Slams or an Infinity IRS ect. are needed to accurately reproduce slam. I think we need to hear from Albert Porter or Mike Lavigne regarding this topic.