Titanic Mkiii 15"

[L.J.]

Oh! Very promising results. Congrats on a job well done. Doesn't that peak at 90 have more to do with your mains? What do you have the crossovers set at?

No, haven't done mine yet. Still sounds great though. Just doing it by ear I was able to get rid of what seemed to be a peek at 60. I have put a spending freeze on all purchases until further notice. Don't want to buy more new stuff just before I have to move it, again. May very well have to leave some new stuff behind as it is.

Move it????

Yep, it's the mains. My xover is set to 80hz. I'm gonna see what happens when I change it to 60hz.

[kexodusc]

Move it????

Yep, it's the mains. My xover is set to 80hz. I'm gonna see what happens when I change it to 60hz.

LJ. I'm curious to learn what happens.

What size is your room (w x h x d)? Any 19 ft-ish dimensions by chance? I have a feeling this could be a room mode issue, but you might also try moving the speakers further out from the wall or tinkering with sub placement.

Setting the XO lower could make it worse. If your receiver has a 24 dB/octave filter, you're moving the cut in the 90 Hz region further away.

[L.J.]

LJ. I'm curious to learn what happens.

What size is your room (w x h x d)? Any 19 ft-ish dimensions by chance? I have a feeling this could be a room mode issue, but you might also try moving the speakers further out from the wall or tinkering with sub placement.

Setting the XO lower could make it worse. If your receiver has a 24 dB/octave filter, you're moving the cut in the 90 Hz region further away.

Well I did a few measurements and using a 60hz xover causes a huge dip(-9) right at the xover point. The peak at 100 was still there. I tried playing tones at different volumes and had the same results each time.

[kexodusc]

Well I did a few measurements and using a 60hz xover causes a huge dip(-9) right at the xover point. The peak at 100 was still there. I tried playing tones at different volumes and had the same results each time.

Yeah, it's definitely looking more like a room induced peak at 100 Hz...don't feel bad, I have one around there too.
I did some calculations based on your room measurements, assuming your room to be rectangularish....you have room modes at 94 and 117 Hz (resulting from the 24 ft dimension), 80, and 121 Hz (from 14 ft) and some nasties in the 100 to 125 Hz range from that 9-11 ft slanted roof.

That's not uncommon (and not unlike mine, my room is 24 ft long too!) , but it's a lot of activity in that 90-120 Hz range which is causing you the grief. They should be especially prominent at the 110-120 Hz area...have you tested that high? And again 250Hz and 300-400Hz where lots of multiples are close together, though your room treatment might be softening the last few somewhat, and there's not really much you can do there (and you may not notice it as much?).
This is just the theory based numbers, the presence of your room treatement, furniture, and room architecture is likely to shift those all a bit, so precise peaks are hard to predict, but we're definitely in the ballpark.

You might find changing the sub placement or speaker proximity has some effect, though I expect it will be small. Ideally, you'd have some room treatment to soften the blow somewhat in that 100 Hz -125 Hz range. Even then I'm not sure how much better corner traps would make it. That frequency area is kind of nice though, lower bass is absorbed less by bass traps, and higher frequencies become more directional so their level at the listening position is not altered as much.

I really needed to put a cut on my 90 Hz peak with the BFD, it has a wider Q, so it just filters the sub lower. I flip back and forth between an 80 Hz, and 100 Hz XO for my sub.
Despite popular belief, the higher XO isn't terrible, and my sub at least doesn't really start becoming directional until 100-110 Hz or so. If I ever get around to building the 2nd one, that should help somewhat. I have corner traps that help a bit, but I live with some mess at 115 and especially 140 Hz right now.

Oh well.

[GMichael]

Yeah, it's definitely looking more like a room induced peak at 100 Hz...don't feel bad, I have one around there too.
I did some calculations based on your room measurements, assuming your room to be rectangularish....you have room modes at 94 and 117 Hz (resulting from the 24 ft dimension), 80, and 121 Hz (from 14 ft) and some nasties in the 100 to 125 Hz range from that 9-11 ft slanted roof.

That's not uncommon (and not unlike mine, my room is 24 ft long too!) , but it's a lot of activity in that 90-120 Hz range which is causing you the grief. They should be especially prominent at the 110-120 Hz area...have you tested that high? And again 250Hz and 300-400Hz where lots of multiples are close together, though your room treatment might be softening the last few somewhat, and there's not really much you can do there (and you may not notice it as much?).
This is just the theory based numbers, the presence of your room treatement, furniture, and room architecture is likely to shift those all a bit, so precise peaks are hard to predict, but we're definitely in the ballpark.

You might find changing the sub placement or speaker proximity has some effect, though I expect it will be small. Ideally, you'd have some room treatment to soften the blow somewhat in that 100 Hz -125 Hz range. Even then I'm not sure how much better corner traps would make it. That frequency area is kind of nice though, lower bass is absorbed less by bass traps, and higher frequencies become more directional so their level at the listening position is not altered as much.

I really needed to put a cut on my 90 Hz peak with the BFD, it has a wider Q, so it just filters the sub lower. I flip back and forth between an 80 Hz, and 100 Hz XO for my sub.
Despite popular belief, the higher XO isn't terrible, and my sub at least doesn't really start becoming directional until 100-110 Hz or so. If I ever get around to building the 2nd one, that should help somewhat. I have corner traps that help a bit, but I live with some mess at 115 and especially 140 Hz right now.

Oh well.

Wow. That's just what I was going to say.