Truly low bass is actually rare, especially in music. That's why we all got along for so many years without dedicated subwoofers in our home audio systems. You need pipe organs or movie sound effects to get below 40Hz in most cases. As a result, it's inevitable that the "auto" power modes on subwoofers are frequently subject to "falling asleep." There are ways around this, actually. In my case, I switch all of my power amps (Model 7500, two Model 200's, and the LFM-1 amp) through switched high-current outlets on my power conditioner. A 12V signal from my processor turns them all on whenever it is on, then turns them all off when it is off.


I moved from the Model 990 to an Onkyo PR-SC885 a couple years back because I needed HDMI support for Blu-ray player testing (OPPO Digital). Frankly, my wife liked the Model 990 more, both sonically and functionally.

Not sure if anyone will read this, but I'll pose the statement/questions anyway. I was thinking THX recommendations (which I don't always believe) and Anthony Griamini (sp?) recommend the crossover settings at 80 regardless. Is this a bad thing? Or should it be based on the speakers true low frequency rating? Just curious. Gonk or anyone else, any thoughts?

THX certifies all of the equipment using an 80hz crossover. If all of your equipment is THX and you want to use their reference then 80 hz is their standard. Since most people don't have all THX equipment and most of us have speakers which will play at less than 80 hz we just generally set the crossover to the setting one step above the lowest you mains are rated for. For instance, say your mains are rated down to 40 hz. The crossover could be set at 40 or 60 hz. If your mains have great sounding bass at the lower extreme then you might not want to have a sub interfere with the great sound and might set it lower for just LFE in movies. Bear in mind that the amp driving your mains has to work much harder to produce bass than midrange or treble. Letting the subs outboard amp handle that duty, frees up more power from your amp to supply to the mains. So you can usually play your system louder, and louder always sounds better.

Again, thanks XenonMan. Making some upgrades and just getting my ducks in a row persay. I'd gotten the LFM-1 EX and Plus a while back and now waiting on the 7900 and Axiom speakers. I'm also trying to decide how to divide the power draws between a 20 Amp dedicated circuit and a 15 Amp circuit. Once I tear everything down I'll do more research to see if I have another breaker attached to that room. And waiting on the 978, but that's another story as alot of us know. :-) Have a good one...

I would definitely find out about that second circuit. May even have installed a separate set of circuits with some lightning protection in it. The 7900 is two big for most power conditioners so it would benefit greatly from whole house power protection. We had it installed in our house last year just for piece of mind but I still have all my stuff fed from a dedicated power conditioner/protection.

I know for a fact I have a 20 amp dedicated, and 15 amp in that room. Presently I have two Monster conditioners; one on each. But, if somehow I have a third, I want to make sure everything is divided to the point that if it needs the draw, it can get it without burning down my house. LOL And to agree with a post you made before, loud can be good!!! As long as it's clear and decisive! Appreciate it sir...

The chances of you actually drawing all the power the 7900 can pull at the same time is minimal. Although it is rated at 450 watts to all 7 channels, you would have to have speakers attached to every channel which could handle 450 watts. An unlikely scenario since we almost all have smaller centers and surrounds than mains. All told it could pull a continuous 3200 watss or so in those circumstances. Providing it plenty of power is good for transient response but unlikely to overload two 15 amp circuits which should supply 3600 watts.