Originally Posted by m-fine416
Also, you have stated multiple times that the level matched subs can give higher output than gain matched because of coupling, but you have not explained how that can work. Please address this issue since it is key to your arguments.
I have explained this (I think on page 3). Since you like using equations well I'll use one for another example.
For the folks : (The power measured in decibels, PdB, is equal to the sound amplitude level PA, by the relation PdB = 20 Log(PA)
So, if we take an example like, I don't know, say adding 75 dB and 70 dB's it will yield a result of:
75 dB: 1075/20 = 5623
70 dB: 1070/20 = 3162
sum = 5623 + 3162 = 8785
Sum = 20 Log(8785) = 78.87 dB
75 dB + 75 dB's = 20 Log (5623 + 5623) = 81 dB as expected.
The two sound sources have to be at the same frequency and
in phase. Our hearing is also logarithmic, not linear, in any case.
And in my
case, my subwoofers are (or rather were since I don't have two subwoofers at this moment in time) relatively equidistant relative to my seated location so they were in phase for the most part. To achieve equal levels at my seated location did not require huge changes in gain (like I said before, when I actually had two sub's it was something around 5-7% differences at most) but I also said that the MFW-15 plate amps seemed to have differing gains (I'm not sure if this has been corrected or not) between models.
This is a complete fallacy. The signals add perfectly as long as they are in phase. If you measure the incremental increase in SPL using the db scale, you get an increase of 6 db from two equal sound levels, and something less than 6 db if the sound levels are not equal.
Yes, coupling will occur regardless whether the actual levels are the same. That's fine. I don't think I inferred otherwise but if I did then I'll admit I was wrong. Also 'something less than 6 dB's' could be 3 dB's. A 3 dB advantage is still a noticeable advantage.
BUT, this is only a measure of the difference, and only in the DB scale. In a linear scale the addition is the same either way, and the higher incremental gain of 6 db is added to a lower base level and always results in a lower sum.
Lower base level ? Also, unless I am reading you wrong, our hearing is logarithmic, not linear. Our ears are not linear and don't follow a linear pattern.
That SPL improvement, when dialed back to conserve on headroom could yield a nice difference in low distortion. Level matching doesn't even necessarily mean that gain levels have to be that much different; in my case it's slightly different but the SPL benefit more than makes up for the slight gain difference.
I haven't broken any laws of physics. I just used the existing energy in my room to my