Axiom Home Page Forums General Discussion Home Theater Another Freakin' Sub Post....

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Understood. I'll go find a high-speed line and re-read the MOAP. I still think you could sneak in some pretty effective and aesthetically pleasing bass-traps which AFAIK would also make a big difference.

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Actually, I didn't go into the bass issues too much in that post…. It was about the only thing I left out, though!

I should have mentioned that I did experiment with something else yesterday: Three big "leaf" bags of rags and blankets in the corner of the room behind the sectional. I read somewhere awhile ago that it was an effective, though non-attractive way to determine if bass traps might work. I wouldn't really expect that it would work as well, but thought it was worth trying. As mentioned, I didn't do any metering yesterday, but I heard no difference. If anyone is curious, I'll meter it both ways and post results. I'm a fan (in theory) of room treatment, but when the bass traps are running ~$300 each and you're not even sure they'll work……

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I'm not sure Darla is a great scene for sub tuning

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I'm not sure either in the big scheme of things… but it sure got my sub "chuffing" so I could listen for the noise…!

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End tables are good, though...

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Well, our plan is to ditch the sectional and recliner and replace them with a separate couch and loveseat so the couch can be centered "on the screen". If so, I would look for furniture that has built-in recliners and maybe ditch the coffee table as well. This will "open up" the room and allow for twin 350s!

It looks like the way you would have the subs placed in the pic would create some cancelations problems.Is there a way to put one sub next to the right M60 and the other as an end table directly across from the first sub.This would be the cloeset optimal placement according to the Harman white papers as you room would allow.

If I were going to buy a second sub, I would take a hard look at the 500 instead of a second 350.

Mark looking at your last diagram the middle of the room sure looks bare without the coffee table, you may want to consider an ottoman as opposed to the coffee table. They come in various sizes and I would imagine you can find one that will be smaller than the existing coffee table but will still tend to your needs, i.e. ... feet!

Whenever I was considering 2 subs I was told by both the Axiom and Hsu folks that catty corner placement would probably be ideal while keeping in mind to correctly set the phase for each sub. Like Wid says, maybe one in the corner by your right hand 60 and the other in the corner where you have the existing JBL sub placed in the first two diagrams.

An ottoman's a great idea, you could sell that to the s.o. as a vibrating foot massager. It just happens to cost a grand and for some strange reason you need to watch Star Wars Ep III to make it work.

You could put on one of those CDs of whale calls and really be soothed... a 100 foot whale can generate lots of nice LFE for the foot massage

>>Actually, they're really not fitting the "44Hz, 88Hz, and 132Hz" math too well.

I went back to the MOAP and looked at the graphs. What I saw was :

- a huge honkin' peak at 44

- a hole around 100 which swallowed the 88 hz peak, presumably caused by cancellation between sub and M60s around crossover freq, which you could might be able to address with the Phase switch on the sub

- small bump around 133 but too small to matter

If you still have that big hole around 100 hz, try flipping the phase switch -- it should help. Then you'll have an 88hz bump to fix, but it's easier to BFD down a bump than it is to fill in a hole.

Hey John:
Thanks again for your input! The plot on the MOAP was an old plot from a different sub position. Give me a little while and I'll post a new plot for the current sub position by the radiator.

Mark, on your question about a sub exactly in the middle of the room, the benefit is that there's the point where both the modes for length and width are at a minimum(to also get to the minimum for the height mode, the sub should be raised half way to the ceiling). The disadvantage is that the lack of reinforcement from the room would lower the sub output. The Harman paper which I mentioned and Rick linked studies a lot of possible locations. Middle of opposite side walls, for example, is at the minimum for the length mode and although at the maximum for the width mode, they're of opposite phase and tend to cancel. Diagonally opposite corners are at the maximum spots for both length and width modes, but being of opposite phase tend to cancel those modes.