WakeJunkie

[quote name="Ron" Are you using metal rack shelves too? If not what are you using for shelves? If so do you have any vibration problems? I am using metal shelves. I had no vibration issues until I put the two 18's in an IB right next to it. Tightening screws and filling all screw holes took care of the shelves vibrating. I still have the problem with the piano bench upstairs walking down the hall during every action movie, but at least I don't hear the shelves. Run a bead of silicon between the rack rails and the enclosure. That is where vibration is giving me trouble since the rails were only attached top and bottom with lag bolts.

My wife would flip out if I ran mine flat.We spent how much for this pissy bass? Lol When flat you have to turn it up so loud for music to thump that it is uncomfortable to listen. I would have to check again the exact DB, but it is no less than 6. To me running the 18's flat I might as well kept the 15". Your ears don't hear flat, you have to boost the lows for it to sound even unless you auto cal does that already. I am not auto calibrating. Setting mine with SPL meter.

Just to report on the subs performance. I watched Iron Man and the Incredible Hulk tonight. It was like watching movies for the first time. Hulk never impressed me before. I loved it tonight. I loved the way you felt every gunshot. You could feel it in the beanbag physically moving from the pressure. In your chest every explosion. My wife even commented on how she was worried the bass would be overwhelming and annoying. She said it worked out perfect. She even said "those movies are much better when you can feel them." Two FI IB318's really pack a punch. Needless to say...I am still very impressed.

Just to report on the subs performance. I watched Iron Man and the Incredible Hulk tonight. It was like watching movies for the first time. Hulk never impressed me before. I loved it tonight. I loved the way you felt every gunshot. You could feel it in the beanbag physically moving from the pressure. In your chest every explosion. My wife even commented on how she was worried the bass would be overwhelming and annoying. She said it worked out perfect. She even said "those movies are much better when you can feel them." Two FI IB318's really pack a punch. Needless to say...I am still very impressed.

A pretty easy way to vent your rack area since you back up into the attic is to use one of these 120V inline A/C booster fans. Put a standard air vent grill in the closet. Run duct to somewhere in your house you can dump it (hall etc) and put another grill on the output. Put the fan on the output end so you can't hear it from the theater. You could put a small filter in the rack area if you have room for it. Trigger the fan when the amp comes on.

My rack is pretty simple. Frame it out with 2x4's 1/4" larger than needed for the 19" standard rack rails plus whatever finish material that will be visible behind it. That gives you enough room to shim behind the finish material to get it perfectly plumb. Mine is 1/2 cabinet grade plywood. Build the rack surround as a box and install it between the studs like you would install a door frame. Rails were purchased for $2 each from "technology surplus" store locally.

I will take sweeps from other positions and verify which is best for the entire room. If it cleans up the center seat and bar then it is a no-brainer.

No gain adjustments made. Subs are still running hot. I really didn't have enough time to do much last night with Church. I needed to clean up for everyone coming over for the Avengers movie marathon that starts tonight.

Green line is with polarity normal. Purple line is with polarity reversed. Both taken from the bean bag. I ran out of time and didn't get to take the rest of the readings.

I ran the sweep with the system set at listening levels, or about 10 dB hot. That makes sense. I will try it flat. I may not get to this week. Have friends coming over for Avenger movie marathon Thursday, Friday, and Saturday. Watching all 8 Avenger movies before going to see Captain America - Winter Soldier on Sunday. Yes...we are nerds.

For some reason my auto-test will not run. Ran fine before, but now gets mic error. I have two mics with the same result.

At the speaker terminals?

I don't have enough material to run 2 full floor to ceiling traps without using up what I saved for a few 2" high frequency panels. Even using that I don't think it would be enough. I have never tried the distance change. I will do some test and see what I can come up with.

I agree. The beanbag is primary, but I really want to fix the Center seat since that is where anybody coming over to check out the system will tend to sit. I may have to retest the center seat. The foosball spot seemed to be the worst for it. It helped with the dip at 57Hz. I don't know how it would be possible, but it had a huge dip at 33Hz. It had a dip already, but it was much worse with the trap than without. Problem is I really only have two corners I can put traps in. For the Center seat the trap by the popcorn machine had no effect above 20Hz at all.

REW project file: http://www.soleproductions.com/Shaun/AVS/SPL Test Full.mdat I was only looking at the "All SPL" tab. I am new to REW and open to advice from any experts.

The bass trap I am testing with is not finished, but acoustically should be the same. 18" on the short sides of the triangle.

All the REW sweeps were with the mains hooked up. The problem is that the subs are turned up higher than the mains. I hear everyone say you should have a flat response all the way across, but frankly that doesn't sound good to me, my wife, or any of my friends. If I set the sub to the same dB level as the mains they are very underwhelming and that has been the case for all subs I have ever had. I am running about 10dB hot on the sub so the mains really can't help with the lows very much. After doing these test I thought about what you said before about changing the crossover and moved it from 80 to 120hz and that helped some with the dip at 80Hz. The dip is still there so I may be dealing with a null at that point also. Mains were still set to "large" and are basically full range. Also, the 5hz peak appears to be a result of positive reinforcement. It drops when traps are in place.

In the legend you will see a name or name - PC or FB. That is identifying where the bass trap was located for the test. PC next to popcorn machine, FB next to foosball table. No suffix then that was the test with no treatment.

Started playing with REW a bit and really like how easy it is to do sweeps. Using my RadioShack SPL meter for the mic and using the calibration files on Hometheatershack.com. This was taken from the beanbag. Definitely the best seat in the house acoustically as well as comfort. This is the baseline taken with no Bass traps in the room. Room was dead quiet when testing. Even turned off the projector so no fan sound. SPL would not pick up any readings on its lowest level.

Youth, you are definitely a great father. That son of yours is a chip off the old block. You have good reason to be proud of him. It is great to see motivation pay off. Not a bad deal that you get a PS4 in your HT out of the deal either. Looking forward to checking it out.

I most certainly disagree! Of course I may be a bit bias...they are in my HT now.

If you're feeling playful, change the crossover to 60 or even 40 and run another sweep. Curious on your thinking. Why set the crossover that low? Isn't the 50-60Hz the chest thump bass? Yes it is. Your mains should be able to handle that if you've got a decent amp behind them. I was thinking that lowering the crossover point MIGHT get rid of a few dips as you'd have less bass sources, less chance of cancellation. Can't hurt to try, you can always switch back. Every room is different, sometimes you find the right sound by accident or by just trying different things. I think my mains are set at 45Hz and I've got plenty of punch in that region. I also have 300 watts on each speaker. The test I ran were with the mains disconnected. I need to run some test with the mains at different crossover points.

Without it my concrete room is one big echo chamber. The beanbag was a great acoustic treatment. It eliminates the first reflection point on the floor for the theater seating and bar area. A coffee table is a hard surface and not really comparable to 150 cubic feet of memory foam. The beanbag is mine and my wife's primary listening position. As you can see from the charts above it is currently the best location in the room when looking at nulls. Besides the fact it is the most comfortable furniture you will ever lay on.

If you're feeling playful, change the crossover to 60 or even 40 and run another sweep. Curious on your thinking. Why set the crossover that low? Isn't the 50-60Hz the chest thump bass?

Is it as comfortable as one would imagine ?As I am currently laying on it using Spotify as my JukeBox I can actually say it is better than I ever thought it would be. Guest fight over who gets to use them for beds. We have two, one in the HT the other in the living room. Had them for about 7 years and still love them. The 8ft is big enough for the entire family with room to spare. Realize it is HUGE. It would hang off all sides of a king bed.I recommend them all the time. Comfysacks.com is having a big sale right now. You will not regret it.