I am a bit of a novice when it comes to bass management, but based on my speaker specs...center: 35hz-22khz; fronts: 20kz-22khz; surrounds: 38hz-22khz...what should I initially set the 950 crossover for each set of speakers? I know the sound will be different from system to system, but what would be a good starting point?

If it were me, I'd start with the center and surrounds crossed over at 40Hz and the fronts set to large (completely full range).

You might also play with crossing the surrounds over at 60Hz and see what it does. Do you have a sub, or are your mains handling all the low frequency? If you do have a sub, you might experiment with crossing the fronts over at 40Hz too, and maybe even bump the center up to 60Hz.

My system has low sensitivity (89 dB) speakers all around, so to lower the load, I started crossing over my speakers at 80 Hz to lower the load on my somewhat challenged amp, even though all would indeed run full range. For my system (two subs) and tastes, this was a good solution. I achieved a higher SPL, with a minor bump in the frequency response. I would only suggest this if you have an overtaxed amp and low efficiency speakers, as that is my case. If I had more power to play with, I would attempt to run my speakers full range. Personal taste is always a factor, though.

S.

Hi,
byrnebv, you think YOU are a novice - heck, i'm 38 and have had stereo equip all my life and I don't have a clue what you are talking about.

i'm going to buy a 950. have a simple DTS receiver now in my home theater.

is there a primer on understanding what you guys are talking about? i have 3 polk audio fronts and a subwoofer, but i don't understand what the crossover is for or how to set these levels. i don't think i can set them on my temporary receiver, but would like to know for january when i get the 950

thx,
jaymer...

what polk speakers do you have? i have the polk sda2b.

scott

I don't know of a good primer for bass management. The ICBM manual might be pretty informative, as I recall it had some good information on how to determining crossover points as part of the setup documentation on it.

Quick description of what the concept of crossover is: many speakers (particularly bookshelf speakers, but also most towers as well) can not reproduce sound all the way down to 20Hz (which is basically the lower limit of human hearing). Instead, we rely on the subwoofer to handle everything from 20Hz on up to somewhere around 60Hz to 120Hz (or higher). In Dolby Digital and DTS (and to a certain degree Dolby Pro Logic before them, but we'll ignore DPL for the moment), there is a separate channel of sound that is purely low frequency, but the other channels are still "full range" -- meaning they include sounds as low as 20Hz, and that information will by default go to your main speakers. If they can't reproduce sounds that low, the sounds will be lost and there will likely also be some distortion or undesirable noise from the speakers attempting to go beyond their range. In order to avoid that loss and noise, we'd want to use the subwoofer to take care of the low frequency sound (and since very low frequency sound is largely omnidirectional, it works out OK to gather the low freq. from all of the speakers and send it through one point). That's where the crossover comes in -- it strips away the sound below a certain frequency from the speakers and re-directs it to the sub. The problem is that we all use different speakers, and the lower limits of those speakers vary -- so you can't just say "we will take everything below 60Hz and send it to the sub" since some people might still lose some sound (such as if their speakers couldn't handle below 80Hz, or if they want to make more use of a sub that sounds best if it handles everything below 100Hz, for example). So you have to make the crossover control be variable. And since most of us use different speakers for mains, center, and surrounds, it would be nice to be able to assign different crossover points for each group (it's worth noting that this capability is currently extremely rare, but will be included on the 950). For example, my mains are rated to be able to get to 40Hz pretty reasonably, but my center really can't go much below 50Hz and my surrounds probably not below 60Hz or so (maybe higher). More extreme variation is fairly common.

That didn't end up being a very quick description, but it should give you an idea of what all the crossover fuss is about. Anyway, you can also take a look at the ICBM manual (start around page 10 -- the manual is available on Outlaw's site) for more on the subject. Hopefully the 950's manual will provide some sort of advise on bass management, too, since they are including several different bass management schemes. Your current receiver may allow you to set a single crossover point for all of your speakers, but it is also possible that it doesn't give you any capability for bass management, either.

awesome explanation (at least for me)

the other day I noticed a LOT of low noise coming from my center (only in 1 particular scene, but can't remember what it was) and couldn't help thinking that something was wrong - but it was hard to tell if it was really intended to sound that way or if my center was distorting. at least with this info you've provided, i'll be able to evaluate the specs on my simple Polk Audio RT8s and the center and be ready for the 950 - thanks!