Originally Posted by BobL
A crossover is not a cut off point. So a crossover set to 40hz will send frequencies to 20hz and lower to the speaker.
I think this needs some clarification for audio newbies. Yes, a xover is not a brickwall device and instead it works on a decreasing-output basis as it encounters frequencies further away from the xover point*, but I think the way this statement is written will make most newbies think frequencies below that 40Hz cutoff setting will be basically just as loud as 40Hz, which is NOT the case.
And: no competent mixing engineer is going to place frequencies below 20Hz into the L/C/R/SR/SL channels. That's what the LFE channel is for. As far as below 40Hz, I highly doubt it but have been considering asking publicly if any members here have done any tests on various soundtracks to find out what IS contained in those satellite channels in the typical multichannel movie soundtrack.
Whenever you push a speaker beyond its frequency limit you increase distortion and limit its output. Plus most speakers frequency rating is at -3db and not flat. So the speaker is already starting to reach its limit. This reason alone should be reason enough not to set your crossover to your speakers low frequency limit. Let your subs do the low frequency work and you will get cleaner and louder output from your speaker.
I agree with all this for the most part. But the thing is, since I'm not really an audiophile, I am not bothered by a (potential) increase in inaudible
distortion, plus I don't listen at reference level so am not concerned about my receiver being overtaxed in the room it's being used in. With surround music, which many times DOES include low bass - not sub-bass though - in all the sat channels**, it can power my relatively inefficient Advents in my little mancave to stupidly high volume levels w/no audible distortion, levels I never listen at anyway.
The best placement for low frequencies is not the best placement for higher frequencies.
True. But if one is not into achieving 100% Audio Perfection i.e. an audio slob
(I'm in that group!), they can place speakers in locations that enable great imaging and the bass might only suffer a little bit.
As I said in another post, personally I like the idea of not
having a bunch of active electronic filters i.e. crossovers in the signal path with all their various cutoff slopes possibly doing flaky things with the speaker's own natural cut-off slopes, not to mention the definitely unwanted interaction of my receiver's crossovers interacting badly with a multichannel recording's own set of crossovers that were possibly
applied back at the studio (last time I did in-depth research on this, there were still no accepted standards concerning this production issue).
Lastly, to repeat what others have said: I just do what sounds best to me
. And using the "large" setting for all MY speakers sounds good to my ears. And, I find it very interesting that pretty much all automatic speaker configuration systems set so many peoples' satellite channels to "large".
* this is written something like this on a receiver's spec charts ----> "cut-off slope: 18dB per octave" FYI: 12dB per octave is extremely common for many speakers' tweeters and midranges, 18dB is relatively common but anything higher is usually avoided because of undesirable sonic effects due to all the numerous components needed to produce such a sharp slope (lots of resistors, capacitors and especially inductors with their many feet of coiled wire). But for an active
xover, such as that used in a receiver's speaker management system, this is not a problem because the components only work with tiny amounts of power vs. what a speaker has to deal with, and extremely sharp cutoff slopes are easily generated which won't cause audible problems.
** for example (all are dvd-audios): Beach Boys "Pet Sounds", Medeski, Martin & Wood "Uninvisible", Linkin Park "Reanimation"