The goal for this article is to make the subject of receiver/processor speaker setup simple and accessible. It's the "how to configure my speakers" article for the rest of us. We'll write a more in-depth article later for those who want to deep-dive, but for now this is a simple overview. Let's get to it!
What Is The Small or Large Setting?
Put simply, this setting determines whether a speaker will be "bass managed".
If a speaker is set to "large", the entire signal for that channel will be sent to that channel's speaker. That is, there is no bass management of that channel.
If a speaker is set to "small", then "bass management" will be applied to the channel. With bass management engaged, a high-pass filter is applied and frequencies below the selected crossover frequency will be rolled off (filtered). Put simply, bass management just takes a little bass from a main or surround speaker and redirects it to the sub.
I know what you're thinking... Why do I want to take bass away from a main channel? The reason is that a sub is almost always better at reproducing bass frequencies than a small- to medium-sized speaker.
The advantage of bass management is that a speaker won't be attempting to reproduce frequencies it can't reproduce anyway. That saves precious amplifier power, increases headroom, and makes more power available to the other channels in the same amplifier chassis.
So, Small or Large?
Set your speakers to "small".
Seriously. Unless you have very large, full-range (20Hz-20kHz) tower speakers, you should set your speaker to "small".
Even if you DO have larger mains, you should still set the speaker size to "small". Just use a lower crossover frequency based on the speaker's capability. For instance, if your speaker is a modest tower and has a frequency response specification of 54 Hz to 20 kHz, then use a crossover frequency above wherever your main rolls off, so 60 or 70 Hz in this case.
Smaller home theater or bookshelf speakers will usually be in the 60-90 Hz ballpark. Very small speakers may even need a crossover setting of 100-120 Hz or possibly even 150 Hz for the tiny pint-sized speakers.
Let me reiterate: unless you have huge full-range mains and/or no decent subwoofer (and if you don't have a decent subwoofer, that should be your next purchase), for home theater, set your speakers to "small". Even if your friend tells you do or even your AVR manual says to use the "Large" setting because your woofers are a certain size, don't do it.
Now that you've set your speakers to "small" to engage bass management, the exact crossover frequency you choose is less critical. It's part science, part art, and you should choose a frequency that works well with the speaker, the sub, and the room. Play with this setting and watch some content to see what sounds best. Listen for bass, clarity, and distortion. Better yet, get scientific and take measurements with a mic and software and see what your room response looks like. We'll do an article on that, too.
Should I Change 120 Hz LPF for LFE Setting?
No. Seriously, the answer is no. There's really only one exception, which is that you're running your subwoofer very "hot" (meaning the level is cranked up high). In that case, you can use a slightly lower crossover on the LFE channel to draw less attention to the subwoofer. You're technically losing some of the signal contained in the LFE channel to do this, but you're trading off some high end to get some more low end.
What about LFE+Main?
Sometimes called "double bass" or "extra bass", with this configuration, the full-range signal is sent to the mains (as if bass management were not enabled), but also copies the low-frequency signal from mains to the sub (as if bass management were enabled).
This is almost never a good idea. The only time the LFE+Main setting should be used is if you have very large, capable towers AND you take the time to use measurement software to align the mains and subs. If you do use LFE+Main and you don't take the time to align the subs with the mains, you will almost certainly end up with nulls - holes in the frequency response. Those nulls may even make you think it sounds better, but it's a mind trick. Your ears and brain are demonstrably poor at analyzing frequency response.
- Set your speakers to Small.
- Leave your crossover at the default 80 Hz setting unless you take the time to read the specs on your speakers and work to find a better setting, which may be higher or lower than 80 Hz.
- Leave your LFE crossover setting at 120 Hz.
- Do not use the LFE+Main setting.