Originally Posted by DaJoJo
small setting on large speaker ? you mean large on small speaker ? i'm not feeling ripped apart i like to learn and on this forum is a good place to do that. i like ur input on the discussion, so don't worry about that. i don't think it confuse others as what we are trying to accomplish is how things actually work and the end result of that would benefit everyone. it is ridiculous doubting audyssey indeed, the question is more which does set it to large ? the audyssey or the avr ? audyssey says to put all on small, but tells us also that it is for common use with movies and music. i wonder now why they have the .1 subchannel in the first place if this isn't a separate track. my english is not so good so maybe some things i say are confusing. i mean not to confuse, but to get it right. if im wrong i like to know too and why i am and i don't feel offended by that.
The basic explanation is that the sub does a much better job at reproducing frequencies sub 60Hz or so.
If you want to think about an ideal crossover you need to have a speaker play flat lower than the crossover frequency for it to sum correctly as you had mentioned in some of your previous posts. This is why we set the crossover frequency ABOVE the -3dB point of the speaker. You don't want the low frequency acoustic rolloff of the speaker summing too much with the crossover as it may cause a dip. We have had some disagreement on this topic because, as with anything audio, things aren't ideal. It is possible that there be a resonance around that point and a dip in the idealized sum between the speaker and sub may result in a flat in room response.
The problem with a large setting is that it assumes that the speaker can handle 20Hz-20,000KHz. Which, for almost all speakers, isn't the case. Most speakers do decently down until the 40Hz point. If we use the small setting at 80Hz this means we have one octave of decay before the acoustic rolloff starts to occur which is pretty good!
As was pointed out, the AVR chooses small vs. large and audyssey doesn't like it but they have no say in the matter. It is ridiculous that Yamaha puts in their manual "Choose large if your speakers are 6 1/4" or larger. They have no knowledge of the frequency response, the in room response, or how well the subwoofer performs in the midbass region. To limit the choice to just the size of cone is silly.
Small is kinda the best of both worlds....you get the low frequency information sent to the sub where it typically is produced with less distortion and possibly with more dynamic range...and the speakers continue to get information where they play best as well. Keep in mind frequency response specifications leaves out what SPL that is done at often. Even when they do specify it I bet most of the time the sub can reproduce 20-40Hz louder than the full range speakers.
Large as you pointed out has no chance to send audio that the speaker may not produce well...and so the sub sits idle for all but 5.1(or higher) content...which is just a waste of money if you ask me.