Best Way to Integrate Subwoofers?

What’s the best way to integrate subwoofers with monitors, or speakers?

I’m not referring to placement, or room treatments. I’m referring to what’s the best way to integrate via a crossover, without a custom dedicated crossover.

Do you run two separate signals to the subs vs the speakers and supress the lower frequencies to the speakers, while supressing the upper frequencies to the subs? It would seem that this method might allow you to move the crossover to higher frequencies, relying more on the subs for the bass and lower mids - if that is beneficial. It would also seem that this method would permit you to taylor the slope of the crossover to minimize overlap of frequencies between the subs and the speakers, which might improve clarity - depending on the capability of the particular crossover used. And, I suppose it implies / requires a separate crossover to be used to run both signals through to route the mids and highs only to the speakers and the bass and lows only to the subs.

Or do you run the same signal to the subs and speakers and just emphasize the subs up to the bottom of the frequency range of the speakers, crossing over from the subs to the speakers at that point (crossover notch). It would seem that this method would require you to fix the crossover at the bottom of the frequency range of the speakers, wherever that may be, and would not require a separate crossover to be inserted into the signal path. And it would seem to imply that the slope of the crossover would be limited to the slope inherent in the subs and speakers, which would limit the flexibility of the crossover.

Or, does it make any difference?
I like the Paul Mcgowan Method - Run a high level signal to the sub/s from your speaker amplifier. Just some extra speaker cable from the same banana's that are going to your mains. This has the benefit of keeping the sound signature of your amp and allows your Mains run full range as god intended. The sub only fills in what the mains can't do. The trick is to find out the best freq to cross over on the sub as you can't rely on the spec sheet from your mains for this. You will just have to listen and experiment. Of course you will need to find a sub that can except high level inputs...
So... I assume that means only the frequencies allowed to pass from the subs to the mains via the mains amplifier are presented by the mains... and... that the controls on the subs provide the various adjustments of how much and how those frequencies pass to the mains (at least for the JL subs).

I did take a look at the JL Audio CR-1 crossover reviews and found this discussion of how the reviewer connected it and dialed in the crossover - which is also very informative.

It appears that discussion, moreless follows your suggestion above.

This all makes sense and is very helpful.    

the crossover goes before the all the amps including the ones in the subs. 

So preamp to corossover to speaker/sub amp. Generally you only adjust once slope and volume of the sub.  

So if you have an external crossover you will to disable the subs low pass if possible.

Good crossovers are are very expensive and a nitch item. If you are just playing with subs for the first time I would look for a sub with a built in crossover (very different from a low pass). I use my built in crossovers and I really can not hear any signal degradation with it in the system. I am sure there is some. But the advantages of the subs far out weight the neatives once set up right. 

Most important is the subs volume. Phase is really hard to hear honesty in the sub range but sound pressure will stand right out. I would get a dB meter and measure the sound at the listiening position using a est CD. 

Jl audio has a document on setting uo phase. It works pretty well, it is online somewhere. 

It will I’ll let you tune the bass to the room which has a profound improvement on the sound. I could never have a system without subs again. Otherwise you need a full range speaker ($$$) and a perfect room and who really has a prefect room? 1% of us, less?

The down side of subs for me is all the extra wires everywhere because I have a 6’ set of leads to and from my subs...


Run full range to mains. Run line level to sub EQ, use sub EQ to integrate.

Cons: You don’t get increased output from your main amp. No extra dynamic range. Sometimes a compromise is to plug ported mains.

Highest dynamic range, most altering of main signal:

Use a crossover after your preamp, before your main speakers.

Cons: Adds more processing steps in series with your fancy DAC/pre and amp.
Pick one.