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

Yes, you feel the wave hit your body with a nice kick drum shot when you are near it, with no amplification. I would call that "slam". Same with the floor tom, which is actually a lower frequency than a kick drum.

During the recent "great recession", I spent most of my time over on the prosound side of things. Imo, there's a lot of validity to Mtrot's observation: "I'm beginning to think the ability of speakers to achieve that sense of dynamic "liveness" may be as or more important to a sense of realism than frequency response accuracy."

On the acoustics side, I take the word to mean unrestrained dynamic transients. Compression can come from amplifier clipping or loudspeaker thermal or mechanical limitations. I believe that the most common culprit in loudspeakers is "thermal modulation", a quick-onset compression that results from the near-instantaneous heating of the voice coil from a high-power transient.

On the psychoacoustics side, "slam" registers when a limbic system response ("fight or flight" startle) is triggered. It is a function of transient dynamics and raw SPL. If there's not much dynamic contrast, it doesn't come across as "slam". If there's good dynamic contrast but the sound pressure level is still soft, it doesn't come across as "slam".

From a loudspeaker design perspective, the solutions include high efficiency and/or large diameter (or multiple) voice coils. If a loudspeaker system is being pushed close to its RMS thermal rating on peaks, your peaks are softened and so is the emotion conveyed. If a loudspeaker system is just loafing along at fairly high SPL, it will deliver plenty of slam. That's why 5 watts into a 98 dB efficient speaker almost always sounds so much more lively than 200 watts into an 82 dB efficient speaker, even though "on paper" both are 105 dB capable.

Duke
dealer/manufacturer

Mr K- Like I said......

After I recently was at another audiogoner's house and saw him working with his banana connections in his setup, I decided to take a look at the bananas on my low frequency run. What I did was to pull a bit more of the cable through the connector and fold the entire cable over on one side of the connector.

What this resulted in was that upon screwing the banana ends back down, it was a much tighter connection and much harder to screw them all the way down. I did this at both the amp and speaker ends of the cables.

Lo and behold, after this free tweak, there is clearly more impactful bass attack. Should have done this years ago!

Now, I just purchased a much more powerful amp, Krell FPB400cx, which should arrive next week. I will be interested to see if the introduction of the Krell will provide an additional incremental increase in bass slam, weight, and control over my current McCormack amp.

MT,

Just wanted to point out that the very act of reattaching the wires alone could result in a better connection than prior, though the folding part probably can't hurt.