Aha - I didn't notice any change in sound after switching to 'LFE' so I looked it up. According to batpig, 'LFE + Main' only sends bass to speakers set to large; the FS52s were set to small on both the 1713 and 2113.
Originally Posted by batpig
Next, if you have a subwoofer, enter the BASS SETTING menu (which in older models is called SUBWOOFER SETUP). The LFE vs. LFE+MAIN setting is only relevant if you have set any speakers to "large". If all of your speakers are set to "small", this setting doesn't do anything. For speakers set to "large", think of this as the "double bass" setting. For more info on the LFE vs LFE+MAIN setting, click here to read a good explanation.
Unrelated: I found this writeup about sensitivity
with a set of examples (not sure if the numbers are accurate though):
For the sake of discussion, take 110 dB per speaker as our goal, 90 dB average loudness with 20 dB of "headroom" for the peaks. This is a commonly used number; enough for a home system, barring huge rooms, absolute head-bangers, and so on. If we could just buy speakers with 110 dB sensitivity, we'd only need a one watt amp. However those speakers don't exist, so we need more power. To be exact, for every 3 dB our chosen speaker's sensitivity is below 110 dB, we need twice the power.
110 dB -> 1 W, 107 dB -> 2 W, 104 -> 4, 101 -> 8, 98 -> 16, 95 -> 32, 92 -> 64, 89 -> 128, 86 -> 256, 83 -> 512, 80 -> 1024
For example, if speaker X has a sensitivity of 86 dB and you want 110 dB of loudness, you need about 250 watts to drive them. The first thing to check is the manufacturer's spec for power handling of those speakers; if they cannot take 250 watts (peak), you cannot use them.
FS52s are 87db, HB-1 MK2s are 92db, S30s are 90dbEdited by Resonate - 1/25/13 at 11:25am