Mike- I'm getting something like this:

http://www.mcmelectronics.com/Home/level_5.jhtml?PRODID=35624&SKUID=34868

The picture has 4 inputs, but if you read the description, it's 3 inputs.

any time there is a summing, discrete status is lost. the filters in digital bass management are just that...NOT crossovers.

the HPFs applied to the satellites allow highs to pass, 1 filter applied to each of the 5 (thus, the 5 retain discrete status).

a duplicate signal is sent to a summing block where the LPF is applied (in the case of the triple crossover, three seperate summing blocks).

a final summing block sums the composite redirected bass signal with the LFE signal. thus, the lfe is no longer a discrete channel. the newly created composite signal is called subwoofer.

and then there is the genius who decided to place all of the sub's controls on the BACK panel.

Or, if you really want to dig into it, at some level a set of data buffers (addresses and size, probably) are passed to a sub-routine that sums them, then the resulting buffer is passed to a routine that performs the LPF.....

Only the CVS guy knows for sure.

Welcome to digital audio.

If someone had asked a few minutes ago to define a cross-over I would have said an assembly consisting of one or more filters. What is your definition? Or did I not understand the point?

Yeah, the term gets misused sometimes, but I always thought of a crossover as the combination of a HPF and a LPF splitting the signal between a sub and high(er) freq speakers...

Well, that would certainly be an example of a crossover (from my understanding) but the common case of a passive network that splits signal into 2 or more bands in a typical loudspeaker was a crossover last time I checked. After careful thought I'm guessing maybe it's the act of signal summing that BoB feels prevents the typical BM setup from being a true crossover?

I'd submit for consideration the classic passive stereo satellites plus a DVC sub-woofer as a litmus test - is it or is it not a crossover, if so or not, why?

I've always had a liberal view of the term, but I'm willing to be educated. I suspect it's maybe one of thise things that there may be no hard and fast rules for use of the term.

it's just easier to get a handle on digital bass management if you use the term 'filters' instead of a crossover.

actually it's an infinite impulse response (IIR)filter that sets the slope and corner frequencies for the high and low pass filters. the 5 full range signals are high passed and then sent to the respective satellites (where they are then passed through a passive 2 way or 3 way crossover in most cases). that full range signal is not passed through a crossover network.

5 duplicate full range signals are summed and level adjusted to create a composite signal. this composite signal is then low pass filtered and then summed with the LFE signal, which has also been level adjusted and low pass filtered. this creates a single digital bass signal which is now called subwoofer.

if that's a 'crossover', then i don't know what kind it is. i prefer to call it a virtual routing scheme of volume knobs, y jacks and filters. it's main selling point is that it's smaller than analog circuits. i suspect that's because the only other points are negative ones.

If it's ever easy.

The current state of things is more complicated IMO due to poor design rather than implementation. The basic concept is flawed at the core, so all the other stuff we do end up being more like bandaids than fixes.

You guys are a great read. This thread has certainly opened my eyes.

I have read about crossovers but now I am beginning to understand.

Keep this up and Outlaw will have a solution and maybe pay you guys royalties.

What if we had a configuration like this:

Settings:

Front speakers set to Large.
All other speakers set to small.
Front: N/A (bypassed because of Large setting)
Center: 80Hz
Surrounds: 100Hz
Sub: OFF

What happens to the frequencies below the crossover points for the Center and Surround speakers?