[medium jim]

To me this is a critical subject, especially with respect to integration.  Some are ridgid and crossover at the same hz no matter the speaker type or capabilities.   Some opt for crossing-over as low as possible.   In my system, through a lot of trial and error, I ended up at 80hz and is a very seemless system with more than excellent instrument placement.

I currently have a pair of Magnepan 2.5's....they sounded good at any point between 50 and 80 hz as the X/O point.  At 80hz as the x/o point the Maggie's sounded fuller and with more sweetness and detail, not to mention a grander soundstage.

When I had my KEF 104/2's, the x/o point was at 50hz and got similar results as with the Maggie's.  Obviously, the gain settings were a bit different and that is where the back and forth listening and tweaking was mostly performed.

Understand, I took a completely unscientific approach and settled for where my ears thought it sounded the best. 

So how did you arrive at the x/o point with respect to your sub integration?

Jim

[JohnR]

My subs are not running right now but in the last iteration I think I settled on 120 Hz - more slam.

[medium jim]

My subs are not running right now but in the last iteration I think I settled on 120 Hz - more slam.

Very interesting!

Jim

[Ern Dog]

I agree that this is a critical point.  Another factor is how you have your sub connected:  running the speakers with a high pass filter and let the sub do all the low end vs. letting the speakers play full spectrum and adding a sub to supplement the low end.  These are very different approaches.  Some say it's better let the sub do all the low end as this frees up the speakers to focus on everything else.  I don't have a high pass filter to try that, so I run my speakers full spectrum and have the sub crossed around 75 hz.  How I arrived at this was by using the free Room Eq Wizard measurement program and a mic.  I tried lots of different cross-over points until I found one that produced the flattest response.  Then I fine tuned it with my ears so it sounded the best.

FYI: for the sub I'm using a JL Audio F110 and speakers are Tyler Acoustics Linbrook Signature System.

[medium jim]

I agree that this is a critical point.  Another factor is how you have your sub connected:  running the speakers with a high pass filter and let the sub do all the low end vs. letting the speakers play full spectrum and adding a sub to supplement the low end.  These are very different approaches.  Some say it's better let the sub do all the low end as this frees up the speakers to focus on everything else.  I don't have a high pass filter to try that, so I run my speakers full spectrum and have the sub crossed around 75 hz.  How I arrived at this was by using the free Room Eq Wizard measurement program and a mic.  I tried lots of different cross-over points until I found one that produced the flattest response.  Then I fine tuned it with my ears so it sounded the best.

FYI: for the sub I'm using a JL Audio F110 and speakers are Tyler Acoustics Linbrook Signature System.

I'm running with high pass that is bypassable, tried both and prefer high passed...

Jim

[Ern Dog]

Is this high pass filter/cross over built into the sub or is it an external one?  Tell me which brand it is.

[medium jim]

Is this high pass filter/cross over built into the sub or is it an external one?  Tell me which brand it is.

Internal, and I'm running separate crossovers between the subs and mains that were custom built for Magnepan type speakers. 

Jim

[pelliott321]

I cut my rebuilt maggy IIIa's at 55hz and bring on my Janis W1's on at 60hz.  By not allowing the maggys go below 55hz they can play louder without mylar slap.
I have 200watt/cha on the subs, using Marchand xm9 and bassis bass management, 250watts/cha on bass panels with class d audio amp , and 60wtt/cha glass on mid/ribbon.  I feel I have great integration. I load the room easily down to below 20hz and the maggys are extremely clean   

[ptmconsulting]

It is critical to understand how crossovers work in order to figure out how best to integrate a sub. Check out Atkinson's technical footnotes on just about any speaker review iN Stereophile. As you will see, crossovers sum at their crossover point.

So generally you want the bass crossover point to be "lower" than the bottom rolloff point for your bass driver in your speaker. That way it will sum properly (since the bass driver will roll off naturally, but usually somewhat steeply). For example, if your speaker is rated down to 50Hz, you probably want your sub crossove point to be about 35-40Hz, then adjust the volume level of the sub to get it even sounding and integrated properly with your speaker.

All in all, if you can hear a sub it is probably crossed too high and/or set too loud. You definitely don't want it crossed too high or you will start getting midrange sounds through it and muddy up your soundstage in that region.

Enjoy

[ricardojoa]

I am using avr, the lowest xover point is 80hz so thats what i use. Higher then tahr sound too knocky on the sub. I then tweak the crossover point on the sfub, usually down to 70hz. For the main i have tried running full range wit ports covered and also high passed. bith yield satisfactory result, s matter of preferenc
The biggest importantce about sub integration is the phase relation between the front and the sub. i have my close to the front, so my settings on distance remain the same from front and subs. The rythmik does a nice job producing deep impactful bass and the peq helps peak and nulls. i mainly tweak my system base on how the sound, i have no measurement to help. But one day out of the blue, i was messing the distance featurre on the avr and reajusted so that the sub are further away. The out come suprised me. I couldnt believe how uniform the best become and how tighter it got. So my experience is that, phase relation is very important in sub integration, but is unforttunevthat i dont have any graph to prove. oh well at lesat they sound good to me....

[jackman]

I used to high pass filter my monitors at 150hz but have since abandoned the HP filters and run them full range.  My subs are EQ'd and run active using a Behringer 2496.  Phil Bamberg used the OmniMic to measure the room and adjust the DCX.  The difference between un-EQ'd bass and EQ'd bass is staggering.  It measures very flat and sounds much better than without EQ. 

After hearing the difference in my system, I don't think I  can ever go back to unequilized bass. 

Old picture...

[launche]

Never would I even attempt to seriously integrate a sub(s) without the aid of these various wunderboxes like the DCX etc... I love wunderboxes.

It seems a cruel joke to play on a common audiophile.

[jackman]

Never would I even attempt to seriously integrate a sub(s) without the aid of these various wunderboxes like the DCX etc... I love wunderboxes.

It seems a cruel joke to play on a common audiophile.

I have a confession.  I thought the low frequency response sounded pretty good without the EQ, but I was dead wrong.  I was using the DCX but without any EQ on the bass and compared to passive "full range" systems I've heard in the past, it sounded pretty good.  After some quick work with the Omnimic and associated software, and some adjustments Bamberg did to my DCX's EQ section, the difference was staggering.  The Omnimic is pretty slick and easy to use!

I'm always sceptical when people make outlandish claims, but I now see the light in this area.  The DCX is modest, I can only imagine how much better things would sound with a sophisticated device like the DEQX (not the Behringer). 

[launche]

I like flexibility, so these wunderboxes are awesome.  I still marvel at the modern AVR, what these things can do for their cost is outstanding and well worth giving up a bit of sound quality if that is the case.  If one of these modern AVR's were made by hi-fi vendors it would probably cost $10K instead of $1k and that would be a shame.

Amazing what these wunderboxes can do in the hands of a skilled professional.  Even just the time alignment pays huge dividends.  I like that feature on the DCX, set the mic up and ping away and hopefully is get things in sync.  When the PRAT things gets a bit more sorted, not having it makes things appear as if in a bit of slow motion and it messes with my brain a little.

[John Casler]

Just a quick thought regarding the XO point.

You need to consider a couple things:

1) Is this a HT System (employing the LFE channel)
2) Is this a Serious Audio System with an actual XO device that low passes and high passes
3) Is this a Serious Audio System which allows the MAINS to be full range,rolling off to as sub that needs to be filtered to fill in after the roll-off of the mains through to the bottom.

All three of these may require a different employment for best results.

So when you write or read about various XO points it is best to have that info so the hinge makes sense in that application.

[audioatlas]

Just a quick thought regarding the XO point.

You need to consider a couple things:

1) Is this a HT System (employing the LFE channel)
2) Is this a Serious Audio System with an actual XO device that low passes and high passes
3) Is this a Serious Audio System which allows the MAINS to be full range,rolling off to as sub that needs to be filtered to fill in after the roll-off of the mains through to the bottom.

All three of these may require a different employment for best results.

So when you write or read about various XO points it is best to have that info so the hinge makes sense in that application.

 

Its very important to be realistic with the fullrange output of the mains also. Trying to encorporate more bass from a speaker that tends to be bass shy can cause issues. Best to just buy a more appropriate main speaker and use subs sparingly. There is a great skill in getting good sub bass with floorstanders.  Generally, lower the xover point the more power you adjust too. Only because  speakers are generally more powerful in their own right. The higher up xover power the less power output since the mains tends to be more bass shy. You don't want lots of bass with bass shy speakers to begin with.  Good post and good advice from you.