Again the topic of weight of amps

mitch2,

     Thank you very much for your interesting and informative responses.  Your, and some reviewers, mentioning the whole issue of truncated bass notes on some class D amps was new to me. After rethinking my experiences with multiple class D amps in my system, however, I completely understand this perception and believe the exceptionally high damping factors of class D amps may be the culprit.  In retrospect, I certainly never heard my Magnepan 2.7QR produce the type of bass that they did when powered solely by my very high powered class D mono-blocks with damping factors >1,000.  I remember enjoying the tight bass but have to now agree it sounded a bit tauter than natural bass heard live.
     Good luck with your new amp rebuilds.

Thanks,
  Tim

@larrykell  I said that I couldn't physically handle a 185 lb. amp.  My current listening room floor can handle a 7.5+ earthquake let alone a few hundred pounds of equipment.

My 1993 constructed prior home had a similar custom 6" slab with 2' exterior footings, 1' interior footings, 8" plate with 6" staggered studs every 8"- no damage from the 1994 6.9 Northridge earthquake. 

@fleschler I guess I misunderstood you and thought you said we should be worried that a floor couldn’t hold that kind of weight.

I put my Gryphon on those little felt furniture pads so that I can slide it around. It doesn’t get moved often but I can slide it a few feet, or across the room, by myself.

When I needed to get the amp moved, I paid my building guys to help move the thing. That’s an advantage to living in New York City. Yes, it’s a pain to move such a heavy amp, but I hope to never have to do that again. It’s a lifetime amp for me, one I expect to keep for decades.

I’m glad you live in a solid structure in California. I never could get used to earthquakes and I went through two small ones when living in LA. I guess I’ll take my chances with hurricanes over earthquakes. It’s always something.

I remember enjoying the tight bass but have to now agree it sounded a bit tauter than natural bass heard live.

^^ This. Overdamped speakers have been a common problem in high end audio for some decades now as most solid state amps overdamp the speakers for which they are intended. No speaker made needs more than 20:1; when damping factors are excessively higher the bass is 'tighter' than real life. To me tight bass is a coloration of sorts; when there is tight bass, bass definition suffers and so does the wallop.

Hello atmosphere,

     I've only become recently aware of the consequences of overdamping on bass performance. Thanks for your additional useful info.
    Like I previously stated, this makes a lot of sense to me when thinking of my experiences with class D amplification.  As I'm sure you're aware, class D amps typically have very high damping factors, my current D-Sonic mono-blocks are >1,000. I always thought high damping factors were a positive factor but now understand it's probably best in moderation.
     Luckily, I utilize the same Swarm 4-sub bass system as you that powers all 4 subs with a 1K watt class AB amp that I perceive as having a lower damping factor.  Do you think I'm correct in assuming the high powered 1,200 watt class D monos with damping factors >1,000, that power my Magnepan 2.7QR main speakers, could be beneficial on the leading edges of bass notes and, combined with the more natural bass note decays reproduced by the Swarm/class AB amp, provide the best of both worlds with a more balanced and natural overall bass presentation? 
     I guess since it sounds like that to me,  that's what's important and I answered my own question.  But I just wanted to know if this makes sense to you or if I'm just fooling myself.

Thanks,
 Tim