Originally Posted by DeltaOne
I've been using a 1019 for about a month, very nice upgrade from my ten year old Pioneer AVR.
Until today I had been using the 1019 with my also ten year old JBL "home cinema" speakers (very much an entry-level 5.1 speaker system). Today I replaced the front left and right surround speakers with Axiom M3ti's (hand-me downs from my son). The plan is to eventually replace the back surrounds and center channel too. Then the subwoofer.
After connecting the M3ti's I re-ran MCACC. It set the M3ti's to large. I had read here before about just changing them to small, but when I did it grayed-out the subwoofer -- so for now I've let them set to large. Why did changing them to small gray-out the subwoofer? Should I change anything?
I have the crossover set to 80. I know the M3ti's go from 60 to 22 kHz, I have no idea what the old JBL speakers do. Should I change it from 80? Experiment to see what sounds best? The JBL "home cinema" speakers are small cubes, about 3" square.
MCACC will set most speakers that reach below 60Hz to Large. Small is best in most circumstances. If you set the fronts to Large, you'll be missing a lot of bass that they cannot reproduce. If they are set to Small, the "lost" bass will be redirected to the subwoofer. On the other hand, the JBL "sub" may not be a lot more capable than your Axioms, so you probably should experiment and decide as you listen for yourself. ("Subs" in many HTIB systems are just woofers, and often do not dig any deeper than typical full range speakers.)
Your JBL "home cinema" speakers probably don't go down below 150Hz, so you might want to experiment with various crossover points.
A high crossover (above ~100Hz) heightens the possibility of localization of the bass, plus you don't want to handicap your fronts for the benefit of the rears. I'd try 80Hz and 100Hz, maybe even 150Hz, and see how it sounds. Many systems have "holes" in the surround bass field, and the owners don't notice, so I wouldn't worry about a crossover that is "too low" for the JBLs. However, if you decide your Axioms are better "Large", raise the crossover to at least 150Hz. Large speakers are not affected by the crossover setting.
Oh, and your sub setting is grayed out when your speakers are set to Small because it is locked into the On position. The AVR will not support a combination of Small speakers with No sub.