where do you cross over your ht setup

In responding to "sean's" comments, i must say that I even used to believe what he recommends about "crossing over speakers, subwoofer's bass quality in general, and general approach to setting up a system properly...but my extensive(much more than his likely..as an edjucated guess) experience, and over 1000 systems, and 1000's of man hours under my belt, I EASILY DISAGREE!!!!!!
tHE REALITY IS, is that playing passive home audiophile speakers full range WILL GIVE YOU A WEAKER DYNAMIC PRESSENTATION, more bass mode challenges to overcome(especially in smaller/medium rooms!), distorted bass woofers(which are underdamped and controlled), lack of extension, weight, authority, impact, and effectiveness, as compared to what the mixing engineers of these block buster movies intened you to hear!!!!!..infact "sean's" recommendation wouldn't hold water for playing back through a speaker system in a large venue either!
People Like Lucas Film, THX, and other mixing authorities have set up the 80hz THX certified paramaters for a reason!.they work! I'm sure some people here(including all the "wanna-be" HT expert/2 ch audiophile "sales-people" I've worked with over the years in 6 stores) would like to think they've got it right, and the REAL AUTHORITIES/EXPERTS HAVE IT WRONG!!!!....YEAR RIGHT!
I'm not saying people can't run their speakers, or shouldn't do thier passive home audio speakers full range for HT!...you of course can. But don't fool yourself into thinking it's better for movies and heavy dyanmic dubties...IT AIN'T!!!
You'll indeed be blowing woofers, getting weaker dynamics, distorted high dynamic bass info, weaker pressence, lack of weight, extension, authority, and a generally lack luster HT playback system!!!!...that's the deal. Not to mention that most people are using very limited, and "iffy" power output from their receivers to driver many speakers full range!!!!!...they're starving their speakers for control!!!...and running into clipping problems!!!
I've seen/heard/done it all before, time and time and time again!
The list of high end and mid-fi speaker gear I've EXTENSIVELY PLAYED AROUND WITH (from my own custom/hobby experience, including 6 audio store I've worked at, and 1000's of hours of custom experience and 100's of clients)
Have included tryinig to run full range speakers of the like's of Willson WATT Puppie's, Large Dunlavy SCV's on down, All the Thiels, Martin Logan Prodigies,Monoliths, etc..., B&W's high end stuff(to 801's), NHT's gear,Mirage's, Snell's, Celestions, Audio Physics, you name it , and more!...and lots of other passive high end gear! I've also played extensively around with most mid-fi gear, including NHT, Paradigm, Def Tech's, Klipsch's, Polk's,M&K PSB's, etc!..and everything you can imagine!!!!
I've tried so many times at making these speaker offerings, using both receivers and separates, play ful range for HT!..it's not as good. YOu GOTTA GET THE SUB TO DO THE BASS!
eXCEPTIONS are, like I said, large full range speakers that have powered subs, like Def TEch's VT3's, Infinity Prelude MTS's(wich I've owned), Avantgarde horn speakers with powered subs', and similar!...also large passive horn pro audio and cinema speakers!
Now, adressing "sean's" recommendation that people simply buy an active crossover, and some passive woofers, and put it together,...well that' just not practical for 99.9% of everyone out there!!...So who's going to do that?..very few!
AS for clains that subwoofers offer generally slow, boomy, slopy, unacurate, "low-fi" bass, well that's also not so accurate!! The reality is that powered sub's do get a bad wrap becasue of larely USER ERROR!!!!!! MOST people don't ever get their sub(or speakers for that matter) set up correctly!...thus affecting the fidelity and quality of the bass they hear! They almost always have the bass turned up too high in level, placed in a bass mode in the room, in a corner, and out of "absolute phase" with their other speakers!!!...it makes getting anything more than cruddy bass mostly impossible! STILL, THE RESULTS THEY GET ARE STILL BETTER AND MORE EFFECTIVE FORE MOVIES USING THE SUB CROSSED OVER TO THE MAINS AT 80HZ!!!!
Again, movies are mixed with explosions, and gunshots, natural dissasters, monster footsteps, and other synthesized sound effects, and other very dynamic overall info! passive home audio speakers can't deal in the bass with this properly! I nkow, I've tried it all before, again and again!..year after year! That's what it is.
Also, yes, many subwoofer manufacturers out there are designing sub's with a built in low "Q factor". This makes for a more "loose", but extended, dynamic, and better power capable design for what movies are dishing out indeed. Still, using this option is still better, IMO, and THX's I think, than the alternative!...it does for movies what they need to!
Now there are companies out there which makes sub's that are more "audiophile" in their sonic qualities, and that pretty much negates all arguments once proper care is taken in setting them up for music/or HT. You can easily pic up subs that have good Q factor, as well as output capability!
M&K's larger MX series, Paradigms excellent, PS1000 to their world class Servo 15, NHT Sub 1, Veldyn'es higher end, Infinity's MTS subs's, Earthquake's dynamite MK1V 12 and 15" digital sub's, and many many others out there, provide not only tight control, but dynamite extension and output!!! Set these up correctly, for proper bass resonse and coupling with the room/speakers, proper phase and coherence with the other speakers, and you can have an extremely high end HT set up that's pretty hard to fault/surpass without getting too custom!!!!
But, to each his own. Still, give me the meat and potatoes over "pipe-dream" audiophile ambitions for proper HT set up, every time!!!!
I'll still put 99/100 people on my side in a set up comparison for a proper HT effort! I know what works...I've lived it, breathed it, and tried it all a bagillion times!!!!!!
peace

I agree with the advantages of running, even "full-range" speakers, as small, easier placement, better dynamics, better bass, etc...

But I find 80hz too high, there is too much info around 80hz that even good subwoofers cant play as well as speakers, and, regardless of what THX and Dolby say, 80hz is still directional, (I have two subs wich minimize that problem), so I use 60hz for all speakers...

I guess no one can answer this one.

Question to you...Why do you think that a cone driver mounted in the main enclosure is superior to a similar (perhaps identical) cone driver mounted in a different box?
Six of one: half a dozen of the other.

Well regarded subwoofers are described as "fast". Surely that is the same thing as saying that they are capable of relatively high frequency reproduction. The subwoofer system that I built includes 15" JBL drivers that were used as woofers in their speaker systems crossed over at 800 Hz. Obviously 80 or 90 Hz is no problem.

I use two REL Strata III and Sonus Faber EAII, believe me, the speakers sound much sharper around 80hz then the subwoofers, thats why I xover at 60hz...

This is not a "cientific" statement, just what I hear...

Yeah really, a good subwoofer/speaker should have no problem playing "accurately"(relative term) up to 80hz! I know I've read and heard many many many times where reviewers talked about the sub they were discussing not being able to play as well up to 80 hz! THIS IS MOSTLY NOT AN ACCURATE ASSESSMENT OF WHAT'S REALITY for many situations! Many subs do just fine, even superb at being played hard up to 80 hz and beyond! There becomes problems with dirrectionality and lack of coherence with the main speakers they're crossing over too, as well as poor sub placment in the room, and improper level matching and such at those frequencies however!...Again, user error!
I will conceed that MANY, YES MANY subs are built to be able to take and playback the much more demanding(less accurate musically i'll conceed) dynamic and synthetic sound from movie soundtracks! This becomes a power handling issue. Thus, they are built with a lower "Q factor", or tightness paramater compared to many music woofers built into many speakers!!!...yes! I know that.
Still, there are NUMBEROUS SUBS THAT NOT ONLY HAVE EXCELLENT EXTENSION, BUT ARE VERY TIGHT(high "Q") and accurate as well! Many THX sub's are such, like M&K's superb MX200/350/5000, etc. Paradigms Servo 15 and PS1000(budget) are very tight and extended!! Infact, for the money, you CANNOT BEAT THE SERVO 15 FOR EITHER MOVIES OR MUSICAL ACCURACY AND IMPACT/EXTENSION FOR THE MONEY, PERIOD! I've found no better sub at this price EVER!!! The higher-end Velodynes are ok. But an other turely dynamite all around woofer is the Earthquake...yes! But there are many others out there at different price ranges and budgets, that have no problem(if set up correctly, which is the downfall of most, conceeded).
The reality, regardless, is that, even with some SLIGHT compromises in some "looser" designed subs, FOR MOVIES AT LEAST, the compromises and trade-off's out-weigh the disadvatages of a potentially truely "accurate" bass note at and around the 80hz range! I mean you can still get truely superb results sonically with a lot of care taken. And I think the advantages out-weigh the con's!
Still, that said, you can negate any real aregument in the debate of letting your more "likely" musically accurate bass woofers in your mains vs. crossing down to a woofer in the HIGHLY DEMANDING BASS reigion for HT, by simply getting one of the better subs!
Think about it..if you were building a subwoofer with a built in powered driver, there should be no reason to think you couldn't design a woofer with better control and accuracy than what an equivalent sized woofer in your speakers offered! This is handled much more commonly by powered full range speaker designs, like those offered by Dunlavy, Infinity, NHT, Paradigm, Avantgarde, Phase Tech, Snell, Linn, Klipsch, JBL, and many others! The woofers in those speakers in mention, are very very dynamic, fast, coherent, and well integrated!..there's no reason to think it's not possible to properly set up an external woofer to do the exact same job, with the same results with proper care and know-how!!
Still, again, for what movies are demanding dynamically, even if you are chosing a less than optimally accurate subwoofer design for your system, crossing over the work to the sub still outweighs any dissadvantage you'll likely need to consider for movies!
Now if you like to listen to your much less dynamically demanding music material "full range" through your speakers, then you can always drop the sub, and have no worries! But for what you need for "thill factor", "impact", authority, dynamics, etc from a movie soundtrack, you simply are making a major mistake by not allowing that all to play properly through your system, by not letting the powered sub handle the dirty, and highly demanding bass chores!!...and that includes up to 80hz I'm affraid.
But, if you are affraid, then just go buy one of the better more accurate subs (paradigm PS1000,Servo 15, M&K MX series, Thiel's expensive sub, Velodyne's HGS(OK), Earthquake Supernova's(superb all around), etc, and you'll have no problems if you set up up right!!!!
I must mention something that I've known for years however regarding bass and overall potential "dynamic transparancy" from a speaker system! That being that passive design speakers and external (even high powered) amp set up's really can't reproduce an accurate(again, relative term...as nothings perfect) and "totally dynamically transparent" pressentation!..especially in the bass!!!
I've known for years, as do many speaker makers, that horns, and active drivers do a much better job of reproducting fundamentals closer to "true dynamic transparancy" with all likely sonic info that's likely to pass through the system! True dynamic control, and thus "accurate playback" of info, from say the bass region, requires as much power and as high of a damping factor as possible! Given most passive speaker systems inability to adequately provide control over the rather inadequately "underdamped" passive crossover network/driver configurations, the lister, ESPECIALLY WITH "UNATURAL" SOUND EFFECT RIDDLED MOVIE MIXES, has to listen to a rather less than optimally dynamic and transparent sonic pressentation, due to physical restraints of the playback system! Again, every time I hear a much more realistic and potentially accurate bass program from "active speakers", much more highly efficient speaker systems, and "active powered speakers" in general!!!! It's just the way it is.
So, for me, any time I can get an active woofer/driver in play, I try to do so if the trade-off's don't outweigh the benefits!
I think, for most peoples peice of mind, they would be better running their audiophile speakers full range for their more likely "less dynamic" music needs, and cross over to the sub to handle the "unreasonablly dynamic" digital movie information! Because inevitably, you know people are going to be facing compromises...I just think doing with I mentioned limites the compromises, and maximizes the benefits and effectiveness of the system for the needs!
It's all good though....