I have a center DYNAUDIO center channel speaker
Two Unity Audio Fountain Head full range speakers FRONTS
TWO Unity Audio Fountain Head funll range speakers REARS
two parts express effect speakers in wall left and right center room.
What do I set the cross over setting at?

I had to hunt a bit to find any info on the Unity Audio speakers, and in the process I think I found a link to your specific system on an old Audiogon forum post. In that post, you listed the range of the Fountainheads as 30Hz to 25kHz. If you have a subwoofer, I would recommend setting the fronts and surrounds to SMALL (which is required to apply bass management) and the crossover to either 40Hz or perhaps 60Hz - either could be appropriate, and whichever sounds best to your ear is the one to stick with. If you have a model number for the Dynaudio center, we could come up with a crossover or two to use for it as well. If in doubt, though, 80Hz is probably a good place to start with the center.

If you don't have a sub, all speakers except the center will be LARGE and the crossover settings for those large speakers won't matter because bass management won't be in effect. The center probably still deserves to be set to SMALL.

New Outlaw, pertaining to the Model 990... I never used the low pass filter (X-Over) in my previous surround preamp (RIP); I ran all speakers full range (even though they arn't) and set my sub to its lowest cut-off so that it plays 50 hz and below.

Maybe that was a mistake all this time. The 990 almost requires that the cut-off be used. If I want the sub to function all the time, I have to select "small" speaker. I was depressed about this initially - especially for the mains which can play below 30 hz. HOWEVER!, because the mains now don't even see anything below 40 hz, they do sound cleaner and faster.

The center and surrounds play down to about 46 hz - my center speaker is a big ugly monster. I tried the 990's 40 thru 80 hz cutoffs for C/LR/RR speakers and the 60 hz has the cleanest integration. I hoped to use the same X-Over for all speakers so that the sub doesn't have to try to reproduce a range of cut-offs to include the associated delays. Seems the sub wouldn't be able to handle the nuances of multiple time shifted excursions. I have the mains at X-Over 40 and the others at 60. Probably the sub is smearing the lows (*). If I had a fast and articulate sub, I might try to cut all speakers to the sub at 60hz, but as is leave the mains at 40 to help the sub to do less. For now, the limitations of the sub is driving my sound set-up decisions.

* - I don't know if the sub content is time delayed to coincide with the surround speakers. If the X-Over and below (that goes to the sub) is not affected by other speaker distances, that would be a cleaner tighter signal to arrive at the sub or is my thinking skewed?

Doing bass management properly (no doubling-up on signal playback) includes running speakers as small unless you have a true full range speaker (which is almost nonexistent). It's not uncommon for people to be leery of selecting "small" when they have physically large speakers (unfortunate side-effect of the decision made back in the 1990's to use the terms "small" and "large" to designate whether or not bass management was applied), but even a speaker that can play down to 30Hz or 40Hz (like the speakers you mention and the Paradigms I had for many years) are still not truly full range speakers. You will obtain a more even frequency response by letting the subwoofer do the job for which it was designed: playing the lowest octaves.

For your case, I'd definitely suggest experimenting (as you seem to be doing) with various crossover points. With the right sub, using a 60Hz crossover for the mains and 60Hz or even 80Hz for the center and surrounds will probably yield the optimal results.


Time delay will be happening after the crossovers, and the delays are meant to allow all speakers' outputs to reach the sweet spot at the same time. The sub gets a delay just like the other speakers, and that delay comes after the signals get redirected.

Hey Gonk,
I've lived with the 990 for some years now, but I never knew in what orser the processing layers were applied. How did you discover that the bass management was applied before the distance compensation?
I sincerly hope we'll meet sometime. I'd think I probably owe you about 20 beers by now.

It has to be - that is the way effective bass management needs to work. The signals need to be redirected to different channels before you add the delay, otherwise your subwoofer signal gets a mix of delays and the output is "smeared" (for lack of a better term).

That certainly makes sense.

It does make sense and I'm glad the sub(s) receives the low fequencies once and not multiple times for each speaker delay. When I visit w/ others, I notice their stereo's sound and often hear a detachment and seperation between the sub (or base module) and the other speakers. I hear this in people's cars as well. The base is a seperate entity from the rest of the frequencies. I can do this with mine to some extent by boosting the sub volume. There is a [narrow] sub volume range that melds with the mains. If too low, the overall sounds is thin, and if the sub's volume is too high, the lower frequency range detaches itself from the whole. Just yesterday I busted out a system set-up cd with warble tones at ...80, 70, 60, 50 40 30 20 10 hz. With the disc, I listened for a change in volume where the mains cross over to the sub. That actually did help; I made a slight udjustment by about 10 minutes on the subwoofer's volume dial. IMO, the sub interface is the hardest to get right. Note that if the main speakers have mid/treble attenuators the base to sub can be fine tuned even more seemless.

Much of the problem can be traced to calibration, as you've noticed - a lot of people run their subs too "hot", or with the subwoofer channel's trim too high.

At the 990, I have the sub @ +15 (no attenuation). I do this so that the sub gets a "turn-on" signal even at a low master volume. If I run the sub where the 990 auto-calibrated it, I have to turn the stereo up pretty loud for the sub to kick in. I use the sub's own volume knob to adjust its volume. Remember we talked about surround (digital) vs analog volumes being much different with the 990? No more startles; I jacked up all the auto-calibration channel volumes relative to each other, and that did the trick. The only thing keeping me from making all channels as if +15 were actual zero is the sub. I max out with the other speakers at 990 channel calibration +12 in order to get the [my] sub to turn itself on early enough.

The low pass cut-off frequency thing is new to me... Sometimes I see my sub has tuended itself off after three minutes of no (or too low of a) signal. Wow, interesting... it's not because of the master volume, it's because there is no sound information below 40 Hz. This just occured to me; last night I saw the sub off and cranked the master volume to some rediculous number like -1 db and the sub stayed off. Back to -25 db and later the sub came on by itself when the "spaceship" rumble occured. I hear the "night mode" works and it does have a bearing on the sub's auto on/off. I could probably use the 990's Max night-mode (min dynamic range) and set all speaker's relative volume level to the sub at the point the sub remains on continuous (with just a trickle). I'm thinking out loud, but that would work to set how loud the master volume is when the sub turns itself on... I might need some pink noise or brown noise for that. I do like the sub to come on with low overall volume because more base is good at low volume.

I don't know what you traded your 990 for, Gonk, but it must be sweet. I'm still trippin' every time I hear my new stereo... the only thing different is the 990. How can it sound like I have more powerful amps and speakers is a mystery to me. All I can say is don't skimp on a preamp, it can make a huge difference!

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.