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Discussion Starter #1
I have been greatly helped by Bryan over the past year and have had a lot of room treatment, I believe I still need a bit more but until then there are a couple of big dips between 100-200hz that i'd like to attend to which I cant shake off.

It seems to be an issue with my floorstanders so I'm using the sub to compensate for the dips. I have tried a few measurements with different crossovers and found that the best balance is set at 150hz, I can't localise the sub, its placed in line with the front mains. It does sound really good to me but I have never heard of anyone crossing bass capable speakers (focal profile 918s) at such a high level, I always had them at 80hz. So I am wondering if there is anything wrong with this at all?

Here are my results, the more uneven response is the 80hz setting, the measurements are sub and mains together, antimode eq on, amps mcaac eq on, pb13u peq taming a big 20hz dip, no smoothing. These responses are pretty much everything as best as can be in the available subs location and seating position and phase settings:
 

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The problem with crossing that high is that your subs are no longer "hidden" meaning that you can hear where the bass is coming from plus it puts a much higher load on the driver and the amp.
Your issues are most likely an issue with phaze. have you tried adjusting that at all or placing the sub in a different location?
 

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Discussion Starter #3
The problem with crossing that high is that your subs are no longer "hidden" meaning that you can hear where the bass is coming from plus it puts a much higher load on the driver and the amp.
Your issues are most likely an issue with phaze. have you tried adjusting that at all or placing the sub in a different location?
I have experienced localisation with subs before but not with the pb13, the same applies here, I cannot tell where the bass is coming from and I've watched quite a few scenes from films on it now.

It seems to add a nice richness to the bass, something my floorstanders seem to lack.

I have measured several positions and tried every phase setting and available listening position. As far as I can tell this is the only way to lift those big dips which are causing a loss of upper bass punch. I spoke to svs regarding the strain on the driver and they said that it will have no problems even if you cross at 200hz it can deal with it.
 

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It seems to me you may have a location problem. I kow you mentiond moing things around allready but think there has got to be a sweet spot in there for you but i do think crossing your mains that high should be unnsessary.:dontknow:
 

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Discussion Starter #5
It seems to me you may have a location problem. I kow you mentiond moing things around allready but think there has got to be a sweet spot in there for you but i do think crossing your mains that high should be unnsessary.:dontknow:
There is a slghtly sweeter spot but its in the middle of the room along the side wall and it is not practical there sadly. Unless I'm missing something it still does not take away the fact that it is the speakers that have that huge dip in the 130/140hz region, it can't be the sub, if I cross the sub at 80hz then it is down to the speakers to take care of the upper bass region. Obviously floorstanders are limited to movement as I still always aim to have the standard 5.1 layout, I've moved away from the wall, closer to the wall, basically everywhere in these corners, when one cancellation null disappears another one appears which is annoying. I have tritraps in the corners too if that information helps :huh:
 

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There is a slghtly sweeter spot but its in the middle of the room along the side wall and it is not practical there sadly. Unless I'm missing something it still does not take away the fact that it is the speakers that have that huge dip in the 130/140hz region, it can't be the sub, if I cross the sub at 80hz then it is down to the speakers to take care of the upper bass region. Obviously floorstanders are limited to movement as I still always aim to have the standard 5.1 layout, I've moved away from the wall, closer to the wall, basically everywhere in these corners, when one cancellation null disappears another one appears which is annoying. I have tritraps in the corners too if that information helps :huh:
Your never going to have a perfect response, but I think you are using one dip to justify a strange setup. Obviously you can decide how you want to proceed, but I'd advise a 100hz maximum on subwoofers crossovers. Ultimately you can do what you feel sounds best because it is your system.
 

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Discussion Starter #7
I have quickly remeasured again to see if anyone can figure out whats going on, the 150hz cross adds a nice richness to the upper bass, I can't see why, I was wrong though its not the mid 100s, its around 100hz and 170hz

blue - mains only
red - sub only
black - sub and mains crossed at 150hz
 

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I have quickly remeasured again to see if anyone can figure out whats going on, the 150hz cross adds a nice richness to the upper bass, I can't see why, I was wrong though its not the mid 100s, its around 100hz and 170hz

blue - mains only
red - sub only
black - sub and mains crossed at 150hz
Slightly above 100hz is definitely a narrow room mode. How many subs are you running? The more you run the less localization you will get.
 

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Why is it a strange set up. If it sounds good to him, it measures well, it's not creating distortion in the Sub from the high crossover, then what is everyone's problem with it?

Your sub is located up along the mains, so what localization could there be?

Maybe I'm completely wrong, but I'm a bit puzzled by the responses.
 

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Discussion Starter #11 (Edited)
Slightly above 100hz is definitely a narrow room mode. How many subs are you running? The more you run the less localization you will get.
I'm only running one sub. I was wondering maybe the reason why the bass sounds more punchy with it crossed high is because the sub is better at dealing with bass, that's all it has to do. Would it not then allow the speakers more headroom?

Will those narrow room modes be noticeable to the ear, i.e. causing minor bass suck out so I would miss certain details in a soundtrack?

I dont know how else to fix those room modes, my listening position are very limited because if I move any further forward or back I'll either be too close to the big screen or too close to the back wall and the surrounds will be in front of us (they're fixed to the wall)
 
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