# blending in mains and DSP1124p



## PoorSignal (Jul 23, 2009)

First picture is subwoofer only, EQ applied to follow house curve

2nd picture is when mains turn on, receiver cross over at 80hz.

3rd picture is longer sweep for main's volume. As you can see mains are already few Db below target on average. However activity is heavy in bass region and lifting up my house curve. This is the phase that works best, the other phase settings have a big null.

Suggestion please... I am not sure what to do. 

Plugging the signal through the DSP1124p result in a higher volume by about 2-3dbs. Is that normal.
I initially put the unit in bypass mode and played a passage and the LEDs range looked good to me.


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## PoorSignal (Jul 23, 2009)

I got curious why the L R speakers seems heavy on bass, so I turned off the sub

I have my mains mounted 6' tall on the wall aimed down so maybe I need to install those foam plugs that came with the my energy speakers to cut out the heavy bass?




1st pic
Left speaker only no sub

2nd pic
Right speaker only no sub

3rd pic 

both speakers no sub


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## lsiberian (Mar 24, 2009)

You need to raise your crossover point if you hear boom from your L-R speakers. Given their near wall placement the Baffle Step is probably responsible, but raising the crossover point will help with that.


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## glaufman (Nov 25, 2007)

It actually doesn't look to me like the mains are lifting up your house curve at all. If you're basing that on your second plot, that's not fair. You're displaying a subwoofer target curve while sweeping more than just the subwoofer (main speakers are on). A fair target curve in that region would be of the "full range" type.
I suggest you display the house curve on a "full range" target, then turn on both the mains and the sub, run a sweep up to 200Hz, and you'll see a decent representation of how the sound is blending. Then, if you don't like what you see/hear, you can go from there.
The mains only plots are certainly showing some nasty things in the bass region, but since they're below the crossover, and don't show up on the combined plot, they may not be affecting thing too badly.
As lsiberian said, one way to tell would be to raise the crossover point, but there are downsides to doing that such as localization of the sub, so IF it's affecting the sound, it's better to play with placement. But play around and see what works.


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## PoorSignal (Jul 23, 2009)

Here is with the full range target displayed.
I think, I have something in my room that excites about 55hz. whether from sub or main. 

I will get some room treatment up and re-measure, or EQ it out from the speaker channels.


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## glaufman (Nov 25, 2007)

See if REW can pick that 55Hz up with no input... could be hum, or ... do you have a refrigerator in the room?
If it's not extraneous noise, I'm not sure I would worry about it too much. Can you hear the peak when the sweep is running?


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## PoorSignal (Jul 23, 2009)

I tried real time but couldn't found any noises at 55hz, I thought it might be my computer but it isn't nearly so loud though.

I EQ'd each L and R speaker using 1 band 50hz to try to tone down the peaks a little.
The result is only half a db less in the 55 peak. Now the curve follows slightly better. 
Here is the before and after so you can see the difference.

When I get some 4" insulation material hopefully I can randomly place them out which furniture or corner is contributing to the 55hz mode.


So far the curve has similar bass feeling like the theater.

The L R speaker are still bass heavy on their own, as you might remember seeing the output of my mains going futher and the volume drops, but I don't really care as much about the high pitch noises 1000hz+, not much I can do about it at the moment.


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## glaufman (Nov 25, 2007)

I wouldn't worry about those small variations like that... unles they seem to be ringing out... you can check with a waterfall.


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## Mario (Jun 2, 2009)

55Hz sounds more like a room mode to me. You won't be able to get rid of it with light treatment. What are your room's dimensions? 

I had a similar problem with the mains throwing off the FR below crossover. The trick was to equalize the entire system, not just the sub. Also make sure the front speakers are set to 'small' in your receiver. Otherwise it may try to send some LFE information to your mains.


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## PoorSignal (Jul 23, 2009)

Maybe someone can help me explain a phenomenon I am experiencing.
It seems since I added the DSP1124 and this house curve the movie have some weight, pretty good,
but I noticed at relatively lower volume the bass is somewhat not clear, muffled, distorted?, exaggerated maybe.

If I crank it up to niceloud levels, it seems the bass is great (maybe too much vibrating in my pants make me think it is aweome) Maybe the mains are louder and covering up all the defects. Sounds great.

Are the levels not moving up proportionally. 

Also it seems my 12" sub isn't cutting it anymore with such a house curve, comparing to a flat EQ tune, the sub now needs to be 7db louder at the lower frequencies. This requires over 4 times the power from the amplifier doesn't it? at such frequencies isn't particular strong and comfort zone for a 12" sub either.
I am looking for upgrade soon.


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## Wayne A. Pflughaupt (Apr 13, 2006)

PoorSignal said:


> Maybe someone can help me explain a phenomenon I am experiencing. It seems since I added the DSP1124 and this house curve the movie have some weight, pretty good, but I noticed at relatively lower volume the bass is somewhat not clear, muffled, distorted?, exaggerated maybe.


Not sure what you mean - “not clear, muffled” and “exaggerated” sound like contradictory or opposite problems.



> Also it seems my 12" sub isn't cutting it anymore with such a house curve, comparing to a flat EQ tune, the sub now needs to be 7db louder at the lower frequencies.


Lower frequencies typically need greater SPL levels at lower levels. That’s what the house curve compensates for.



> This requires over 4 times the power from the amplifier doesn't it?


Actually, virtually any equalizing places additional demands on both the amplifier and driver. It’s only an issue if you run out of headroom.

Regards,
Wayne


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## Wayne A. Pflughaupt (Apr 13, 2006)

It also occurs to me that if you have the Dolby Digital compression option engaged that could cause the problems you're describing.

Regards,
Wayne


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## PoorSignal (Jul 23, 2009)

Source is lossless audio, I think maybe the curve is too much for my 300W plate amp and 12" subwoofer to handle. A pro amp and 18" sub should handle that better


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