Axiom Home Page Forums General Discussion Home Theater Major sub issues

If all else fails, putting a cushion on the sub and sitting there usually works

Apologies if this was already covered and I missed it - but have you checked that the sub doesn't have any kind of crossover filter engaged? Is it possible your W's are crossed at 80Hz and your sub is filtered above 60Hz creating that hole in frequencies you are experiencing?

Good. This may make a big difference. Dan's observation about disengaging the sub crossover is very good, too.

It's GOT to be a placement issue.

The sub crossover is disengaged, and the knob is turned up all the way (200 hz I believe) for good measure. I have the phase set at 0.

As I said in the AVS thread, I was able to get the sub to crank out some serious couch-shaking last night, but I had to crank the gain, its level was way higher than the rest of the speakers.

I do have the Denon Bass Setting to "LFE", which is says reverts all LFE from any speakers set to "small" and passes it to the sub. This seems to me to be the correct setting as all my speakers are set to small. There is also an "LFE + Main" setting which sends ALL LFE info the sub, regardless of speaker size setting, but in my case I don't think it should matter since they're set to small anyway. I can't remember what I have the low pass filter in the receiver set to, although default is 80 hz and I doubt I changed it. Maybe I should try 90, or even 100.

Thank you for making this point. This is precisely why I leave my M80's set to large even when I have a subwoofer. Expecially a subwoofer designed to dig really deep like the EP800 is. We've already discussed the fact that subwoofer designs are all trade-offs. You trade this for that. With subs like the EP800 tuned to hit 12 hz in a room, you give up some of the ability to do 60 - 90 hz really well. This is the reason some cheaper subs costing only a few hundred dollars seem really impressive as far as slam goes. They might not play much lower than 25 hz, but they can hit 60 hz like a M1 Abrams tank slamming throught your living room wall at 80 miles per hour!

I still say it's personal preference. But for me, the M80's take care of the slam much better than the EP800 did.

I see you had the phase at 0 but have you played with it back and forth in the different locations? Sorry if you answered this in the other thread, didn't read it.

Also, when you were saying the gain was way up, is that on the receiver you're referring to? If so, it could be the signal just needs to be cranked on your receiver? And I don't think that should be an issue, not ideal but it should harm anything...chime in experts

Well, I feel like a bit of a dork (as if that isn't obvious anyway ), as I decided to just start from scratch tonight, and noticed I had the low pass filter in the receiver set at 250 hz . I guess I raised it to max for the Audyssey calibration and forgot to reset it back. I changed it down to 80 hz and noticed a decent difference, especially in the front which I was complaining about earlier. I guess with the filter that high, the fronts aren't getting a full range.

After all this I re-did the sub crawl, and decided to leave it where it is. It's 10 - 12 db higher than other areas of the room there and is mostly not in the way. I re-ran Audyssey, bumped it a couple db, and I really think that is all I can do with it.

I think the best course of action from here is to purchase another, smaller sub in the future, and probably place it in the other rear corner. I'm just annoyed I sold my old one before testing this all in the first place. If I do this though, is there any way to limit the amount of LFE sent to it? I guess it would be a high pass filter which would limit the lows so I don't overdrive it while the SVS is walking in the park.

On that note, does anyone have an EP175 they want to sell?

You're in luck. Axiom has a subwoofer by that name.

You're not looking for the location where the sub sounds the loudest. You're listening for smooth, even bass. If it sounds loud, it may be that there's one frequency piling up which will make all the others suffer.

I think it is the Digital Video Essentials DVD which has some low bass sweeps, which also show the current Hz on the screen. Anything with a bass sweep would work though. While you're doing the crawl listen to the full sweep in each location, it should sound (or even better, measure) equally loud through out. If using the DVD, you can even get an idea what frequencies are being accentuated or lacking. Sort of a poor-man's REW.