Speaker size and bass


I have a finding and would like to hear what you think.

I always have been using floor speakers in my room thinking the bigger the speaker, the more bass it can produce.  I think this is true based on the physics.  However, I found out a “problem”, that is the listening volume.  
My listening area is 18’ wide x 12’ depth.  It is the listening room, so, I can’t play the music too loud otherwise my wife complaints.  Also, I listen to Jazz and Bossa, doesn’t need to be loud.  It seems that at low volume, it can’t bring out the bass of the drivers.  But if I turn it up, it will be too loud for me.  I think that make sense, the bigger the driver, the louder it gets.

So, when considering the appropriate size of the speakers, besides the room size, is the listening level also a consideration?  That means, for a smaller speaker, is that I can turn the volume knob more, and that will output more power to move the driver more to produce the bass, and yet it will not be too loud?


gte357s

Showing 1 response by millercarbon

Volume isn't merely a consideration, with bass it is everything. Look up Fletcher-Munson equal loudness contours. This is a graph of the way we hear the different frequencies. Low bass frequencies are all bunched together. What this means in practice is we hardly hear low bass at all until it gets fairly high in volume. But then once it crosses that threshold we are really sensitive to the volume level. This is why they used to put loudness controls on amps, to turn up the bass to make it sound right at "normal" (ie not loud) levels. 

The same thing happens at the other extreme, just not as dramatically. The overall result is one fairly narrow range of volume where we hear things in a good balance. (If we ever do. A good case can be made that we never do.) This more than anything else explains why we think things sound best at a pretty high level (way higher than conversational level) but then can't figure out why the sound changes so much when all we did was turn it down a little. Equal loudness curves, that's why.

There is no way out of this trap by the way. Its a psycho acoustic fact of human hearing. As far as speakers go though we don't have to be stuck with giant monsters. Multiple subs actually perform better, and the unusually smooth bass you get from a DBA goes a long way towards ameliorating the problems inherent in equal loudness perception. You still need to set up your DBA levels for your intended listening level. But separating the bass level where the biggest loudness perception shift happens from the rest makes this a whole lot easier than any of the other options.