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

Lots of info here on various threads regarding Class D amps.

I've been using Bel Canto ref1000m monoblocks for a few years now and think those to be rock solid still and a very good value used. That's really the only ones I can vouch for based on extended listening. I've heard other good ones as well in recent years from Jeff Roland and Audio Research. Other that would be of interest for me due to value potential would include Wyred4Sound and DSonic. I would probably avoid older Class D amps in order to access current possibilities in that the technology continues to advance significantly still.

Hypex Ncore technology has really upped the performance standard for Class D. I have a pair of monoblocks for sale right now here on Audiogon if you're interested.

But I would caution that amp power, while important to deliver slam, is not the only precondition. You also need clean and dynamic source electronics capable of driving the amps well. Since slam is about dynamics, if you don't have high resolution and low noise signal, it will blur the dynamics and detract from the slam. We are always fighting some level of dynamic constriction in recordings, some worse than others with the loudness wars, but even really well recorded stuff is much less dynamic than real life. Such is the nature of recording vs live. In order to maximize dynamics, the entire signal chain needs to be clean and clear, and electronics need to have good impedance matching with each other so they aren't strained and have enough "drive" to create that realistic slam. A good preamp is often key to giving that last bit of drive and dynamics to the music.

I also think clean power into all electronics is highly critical. Good in restrictive power conditioning like the Pi Audio units and power cables that do a good job of rejecting and filtering noise can really reduce the noise floor of your system, which in turn increases dynamic contrasts and slam. Of course it also greatly improves imaging, soundstage, and micro dynamics as well, so it's not either/or when it comes to slam and other audiophile characteristics.

Finally, I would say proper management of bass resonance and nulls in your room are vital to slam in the bass frequencies. Untreated rooms are a horror show of bass anomalies that produces varying levels of boom and suck out at different frequencies. If you can use room treatment, multiple subs in a distributed array, EQ, and/ or combinations of these to even out the room response, your system will be capable of producing clean and even bass that will then slam rather than booming.

@ Genjamon,

Thanks for the informative reply! While I have no doubt that your points about certain aspects of electronics are factors in production of "slam", I must note that some of the demos where I have heard and felt "slam" have been at very much mid-fi retailers, who I am confident were not employing any sophisticated, high end pre-amps and/or amps. No doubt, the amps they used in such demos were likely very powerful, but my guess is that the biggest factor in the demos I heard was the speaker being used.

With my limited financial resources, I would be looking for the most practical, affordable way to achieve the most uncompressed, and dynamic presentation. Hence my question about whether "slam" would be mostly a function of speakers or amplification.

If the speaker cannot "slam", no amp will help. The speaker is more important in the slam equation than the amp. There are lots of amps that will make a capable speaker produce slam, but few speakers that have the dynamics to do it.

Anyone who thinks that it is an audio thing does not get out to hear live music much. Even a small drum kit can smack you hard. Course, most audiophiles don't go out to live music, they just talk like they do.

Slam is when you have a speaker on stands and your grandchild runs a football route into one of your speakers and it gets knock up against a wall like body check in hockey. It is very accurate and I hope it never happens again.