I just hooked up my SMS-1 this afternoon and when my system runs the frequency sweeps I have a drastic drop off above 80hz. It seems adjustments cant be made to raise the EQ above 80hz, so is my only option to drop all the other EQ levels down to match the output I'm getting above the 80hz crossover point?

Any other suggestions of things I could be overlooking?

Thanks!

I've also read about people using the SMS-1 sweeps on there mains. I have a 5.1 set up. Do I need to connect more than just the subwoofer to get an accurate frequency curve? I'm a little confused now. Right now I just have my sub hooked up and my response curve is nearly perfectly flat from 20hz-80hz where it then rolls off severely. I must be missing sonething here.

When you get that drastic drop, is it a brief dip or is it an extended step down to a different (lower) level? If your crossover in the receiver or processor is at 80Hz and you haven't got the system and subwoofer/SMS-1 volume levels equal, you will see a sudden and rapid change in level at the crossover point. Check out pages 16 and 17 of Outlaw's SMS-1 guide ( click here to download ) for a guide to help you get the volume levels equal between the sub and the rest of the system.

You need to connect the subwoofer signal through the SMS-1 and then connect the SMS-1's EQ output (both audio and video) to an input on your receiver (the SMS-1 guide I linked to in my previous post can help a lot in explaining what's going on). The SMS-1's test sweeps will run from 15Hz or so up to 200Hz, which will involve both your sub and your mains. This is done in part to help work out the integration of the sub with the mains (adjusting the phase and the volume levels, for example). It also allows the test sweep to work with a wide assortment of crossover points between sub and mains, since not everybody crosses over at 80Hz.

Well some how my frequency sweeps are not going to my mains. The only output I detect is from the subwoofer. I'm at work now so I'll have to wait until I get home to play with it, but I do know that I have my receiver crossover set to 80hz and I still have the SMS-1 crossover set to 80hz. I will turn the SMS-1 crossover off when I get home, but I dont know if that will have any effect on my mains. I guess I can try and turn my sub output down really low or off to see if the mains are producing any sound.

OK after reading page 17 I see that the best method is to start by getting the higher frequencies on the graph and then adjusting the low frequencies to match. I'll try this when I get home, but as far as dips and peaks in the 100hz and up range, the SMS-1 really has no way to address this?

Since you have bass management in your receiver, I'd recommend disabling the SMS-1's crossover (middle of page 18 in the SMS-1 guide).

If you have dips and peaks above the crossover point you've set in your receiver, the SMS-1 can't help because they are taking place in the range handled by the mains and the SMS-1 only manipulates the signal to the sub.

This seems to be about as flat of response as I can get.

Your pic came back! (If the image above is not visible, click here .) If your sub is being crossed over at 80hz you are not going to be able to adjust above 80Hz at all (except to equalize volume levels) because the sub will be out of the picture by that point.

Having said that, I'd say that you've done a very nice job with the sub EQ'ing. I'd probably zero out the EQ control at 100hz since it's not going to do anything useful for you and could actually create problems if the sub gets 100Hz data from a DVD's LFE channel - it'd be a spike in volume at that point, and that spike is only going to throw your overall frequency response off.

One thing you might try is turning the SMS-1's volume down from 20 to perhaps 12 and then turning the receiver's volume control up a few notches - that would bring the sub's output in line with the upper values being produced by the speakers and might help the sub blend with the mains.