Well, the beast is finally alive. Build-up was pretty straightforward. Ran into a few minor snags that required a little thinking to fix. Also got help up waiting for the HS500. Sub is per Dan W's recommendations: 480L 28" x 54" sonotube 6" x 20" ports dual Tempests triple MDF endcaps 8#'s of 1" batting lining the walls and port tubes Went with a grey/black/white flexstone for the endcaps and black naugehyde for covering. Hammertone silver for the legs with rubber feet. DIY grills are 1" wide MDF rings with some routing to look nice and silver metallic cloth. Went for a "modern" look as our family/HT room is kinda modern/art deco or something like that. I'll get some pics over the weekend hopefully. Made a box out of scrap MDF for the amp. Roughly 8 1/2 x 9 x 16. Put some handles on the side and rubber feet on the bottom. Basically I threw it together as I plan on building a better version in the future that will be detailed, painted, etc... So....I plug in the amp and instantly have 7.1 HUM, I mean you can hear it 2 rooms away, thanks to that great Klipsch efficiency! I tried turning down the "level" and it didn't make a diff. Call it "brain fade" or whatever but I thought the power cord was a 2-prong so I didn't bother running out to the garage to grab an adaptor. It was already around 11:30PM so I was getting a little tired/goofy by then. Cranked the "level" back up, or so I thought, I LATER realized that I actually turned up the "bass boost" knob instead. Popped in TS 2 and wasn't too impressed. Next up was JPIII, bass was tight and clean, but not earth shattering, then U-571 for the depth charges. Finally felt some thumping/pounding in my chest and the couch. Still very clean/tight, but not making stuff fall off the walls. Tossed in an AC/DC CD to try some music; again bass was very accurate and not overpowering. Over all I'm happy, but not super impressed. Definitely more accurate than my old sub, but doesn't really hit you in the chest...... It was about 12:00PM by now, yes my wife is awesome, as I'm testing at/near Reference level, and my 3 & 5 year old sons sleep right through it. I'm figuring that maybe I need to test some real low stuff as that's what the Tempests are known for, so I grab "The Haunting" in DTS. While I'm waiting for it to load I decide to mess with the amp one more time to eliminate the HUM. As my tired eyes finally focus on the black amp face in the dark room what do I see: I've got the damn "level" at about 1/3 volume and the "bass boost" cranked up instead!!! DOH!! With renewed enthusiasm I quickly jump to the "water pipes" scene. Crank it right up to 00 on my 3802 (obviously nothing is calibrated yet but this is VERY LOUD) and let her rip. Discovered problem #2; the grills I made are held on with 8 small pieces of Velcro, which suddenly can't do their job as the grills were lifting about a 1/4" off the top of the sub, sort of flapping in the breeze. All you could hear was the sound of Velcro constantly being ripped loose and then resticking itself! Very funny. Problem #3; apparently the silver metallic grill cloth doesn't breathe very well as it was bubbled up at least an inch or two! Solution: remove grills when playing sub So onto the demo: I'm guessing this scene has some very low bass as I'm watching the top sub move violently back & forth, amazing how much travel that driver has, but I'm not hearing much. Then a stack of DVD's fall off the TV, then my oldest son comes out of his bedroom because the cover on the electrical panel is clanking. Then the lights start dimming, then the top 1/2 of the TV starts getting weird lines through it every time the bass hits. YES, this thing is a "homewrecker". My HT floor is Pergo over concrete slab and I SWEAR that the floor is moving!! I can already tell that the drywall will be popping up nails in no time, and basically everything under 50#'s will need to be glued/Velcroed down, including my youngest son. Oh the joys of having bass..... Tonight I hope to eliminate that annoying and LOUD hum. Tried unplugging the CATV and that didn't do it. Will try the 2-prong plug and will also move it to another outlet. Another problem I ran into is placement: I had planned on putting it behind the TV, but the magnet from the top sub can't be within 3'-4' of the TV, and also when that close during heavy bass scenes I was getting distortion/horizontal lines across the screen. Probably won't break out the RS SPL meter until this weekend, but tonight I plan on demoing more DVD's to see what this thing can do at full volume. Over-all first impressions: this thing is friggin' HUGE!! Won't be a problem once it's in a dedicated HT. So far the sound is very tight, clean, and accurate. It appears to have tremendous volume potential and the ability to play VERY low as I witnessed during "The Haunting". For music I have my receiver set to -10 for the sub and the new sub seems to integrate very well at that level. Not overpowering, but provides that bottom kick. Will also try out some bass heavy old school rap and hip hop tonight to see how it sounds. Although my AudioSource put out some decent SPL, it definitely got muddy/boomy when pushed hard. It's now VERY apparent what good/clean bass should sound like. Build-up was a LOT of fun. I'd estimate around $925 total for subs/amp/supplies and around 20+ hours of build time. If you can live with a BIG tube then this is THE sub to build, at least to me it was. More to come....Mike P.S. I would LOVE to let the dork at Tweeter who kept trying to shove a REL down my throat listen to this thing!!