What happened to my bass?


Ok, for those of you willing to read a bit, I have, as usual, something driving me nuts. I'm a speaker builder. Current speakers look like Watt/Puppy, consist of 11 inch Eton, 7 inch Scan Speak, Scan Speak Revelator tweeter. They perform very well and I haven't changed anything about them in 5 years.....but I have changed houses and of course rooms. Prior room was twice the size of the current, rather small, living room. Bass was a tad shy in the prior bigger room which was in a basement with a good amount of exposed insulation and floor joists up above. Current room is plaster covered drywall, bass traps in front room corners. Bass is generally quite a bit better in the smaller room and according to my pipe organ tracks, very low bass is no problem. So, finally, to the point. Yesterday I am listening to Bygone Days (Eileen Ivers violin track) and it dawns on me that that track has sounded different in the past. In fact, on second listen, there are bass notes completely missing that I clearly remember. I assume the memory goes back to the prior bigger, bass-shy room! I just don't get it. My sense is that bass is fuller and more balanced in this room on everything else I have listened to, and then I get to this Ivers track and there are bass notes that actually had some growl to them, completely missing? It's really wierd when you anticipate something in music and it has disappeared. Room null? By the way, it makes no difference where I am in the room. I even stuck my head behind the speakers. Am I the only one whose system drives them nuts from time to time?
240zracer
I can only recommend that you perform some measurements with proper software, sound card and microphone.

(Assuming of course that you actually want to understand what is going on, which is not obvious as most people here on Audiogon prefer to muddle along changing this and that in an endless merry-go-round. Of course each time around the carousel these audiophiles are excited at the new improvement brought about by their latest monthly tweak. And the lack of any rigor in this approach allows them to justify just about any change as an upgrade.)
Shadorne gives good advice. Measure the frequency response if you can.

IMO, it's possible you have a room mode that is resulting in a cancellation at approximately the same frequency as the missing bass notes. It's a little strange that the result is *constant* across the entire room, but I think it's still possible that the explanation is a destructive room mode.

If you cannot measure frequency response, the next step might be moving the speakers to new positions around the room, even extreme positions, to see if ANY change of placement can make the undesired effects go away. If you can make them go away with room placement, then you can conclude that it's a speaker/room interaction. If not, at least you've ruled it out.

Good luck.

Bryon