# calibration done now how to integrate with mains



## apilon (May 18, 2006)

Good evening

i have completed my REW alibration today al in all 6 filters to set here is a graph of my calibration 

Now the question how do i proceed for main speakers integration with the sub i am a bit confuse on the procedure for that one 

Alain


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## brucek (Apr 11, 2006)

Surprising how good the response is below 80Hz. In fact looks like you didn't even use a filter below 90Hz.

But above 80Hz (which I presume is your crossover frequency) it appears the crossover isn't filtering the signal very well. It looks like you had the mains on?

What are your thoughts on this?



> Now the question how do i proceed for main speakers integration with the sub i am a bit confuse on the procedure


Not really a procedure. Just turn on your mains and do your sweep as normal for the sub up to 200Hz. Any negative interaction around the crossover can usually be fixed with filters or phase control preferably.

brucek


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## apilon (May 18, 2006)

brucek said:


> Surprising how good the response is below 80Hz. In fact looks like you didn't even use a filter below 90Hz.
> 
> But above 80Hz (which I presume is your crossover frequency) it appears the crossover isn't filtering the signal very well. It looks like you had the mains on?
> 
> ...


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## apilon (May 18, 2006)

apilon said:


> brucek said:
> 
> 
> > Surprising how good the response is below 80Hz. In fact looks like you didn't even use a filter below 90Hz.
> ...


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## brucek (Apr 11, 2006)

> i had disconnected the 3 front mains but because my avr is located in an AV audio center it is proving a real challenge to disconnect the rear so i guess the rs meter picked them up during the sweep .....


Why not just select STEREO on your receiver, then only the mains need to be disconnected. Why do you have multi-channel turned on?



> i had disconnected the 3 front mains but because my avr is located in an AV audio center it is proving a real challenge to disconnect the rear so i guess the rs meter picked them up during the sweep .....


That's really up to you. Once you did your sub+mains raw sweep and re-checked the boxes to turn your filters back on, you can modify the existing filters or add extras if necessary until the REW graph looks good. Then enter that into the BFD..

I really feel your sub is not turned up high enough in relation to your mains. Turn it up a bit and remeasure at 80dB - you're measuring a bit low also on your REW setup.

brucek


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## apilon (May 18, 2006)

brucek said:


> Why not just select STEREO on your receiver, then only the mains need to be disconnected. Why do you have multi-channel turned on?
> 
> 
> by defaut the avr635 set up the tape input as logic 7 and it did not cross my mind to change it to stereo
> ...


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## brucek (Apr 11, 2006)

> Unlss you think that it would be better to jst calibrate all the mains and sub at 75db or 85db then run REW applied filters than run EZ EQ


No, I think I would first use the processors EZ-EQ and then go ahead and use REW to set up your filters. I would setup REW at 80db, but I would also increase the volume on the sub amplifier a bit too before I started. It looks like the sub is lower than the mains from your graph.

brucek


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## apilon (May 18, 2006)

brucek said:


> No, I think I would first use the processors EZ-EQ and then go ahead and use REW to set up your filters. I would setup REW at 80db, but I would also increase the volume on the sub amplifier a bit too before I started. It looks like the sub is lower than the mains from your graph.
> 
> brucek


I will do that and post back the result


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## JohnM (Apr 11, 2006)

Sub is certainly too low, for your desired house curve it needs to come up about 10dB, you also need filters at the various peaks indicated below - REW isn't suggesting any because the sub level is too low for the peaks to show above the target curve.


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## apilon (May 18, 2006)

JohnM said:


> Sub is certainly too low, for your desired house curve it needs to come up about 10dB, you also need filters at the various peaks indicated below - REW isn't suggesting any because the sub level is too low for the peaks to show above the target curve.


I redone the EZ EQ calibration today had setup the sub volume at mid level but the EZ EQ was overloaded so i turned down the sub volune a little at the time until the overload stopped still AVR 635 EZ EQ corrected the level of the sub -10db but when i tested it with music and movie t was load enough and i was getting 88db on the spl with pink noise 

i then proceeded to the sub calibration with REW with mains off this time and this is the graph i got







You probably gonna tell me that the sub is still low but if i raise the sub volume it is getting way too loud ...so loud i can pinpoint where it is located anyhow



6 frequencies to set from 445 to 500

i then reconnected the mains played music and a movie demo and looks fine althought sub a bit loud 

i then proceeded to main integration with sub and this is what i got 5 frequencies to set from 122.5 to 166 wat i did is set up these one on filter 5 so i can alternate between the 2 and see which one seems to do the better job 

Any thoughts idea are welcome 


Alain


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## brucek (Apr 11, 2006)

> You probably gonna tell me that the sub is still low but if i raise the sub volume it is getting way too loud ...so loud i can pinpoint where it is located anyhow


I don't doubt you can localize it. It looks like your crossover isn't working. Your sub isn't rolling off at all. Look at the target and your signal above 80Hz...?

And yes, when using REW, you must set the measurement level at the target level so REW can suggest filters. Your sub is set so low, REW will never recommend anything below 80Hz.



> 6 frequencies to set from 445 to 500


Sorry, I don't understand this. We're measuring from 10Hz to 200Hz. What is 445 to 500?

brucek


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## apilon (May 18, 2006)

brucek said:


> I don't doubt you can localize it. It looks like your crossover isn't working. Your sub isn't rolling off at all. Look at the target and your signal above 80Hz...?
> 
> 
> I followed some instruction from another HT forum for setting up my sub volume at half point phase a zero and crossover at the highest settings then set the crossover point in the receiver at 80
> ...


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## apilon (May 18, 2006)

one question that just pop my mind i set the spl at 75db as per the help file instruction but when i do the rew spl calibration which figure do i enter in the box before pressing done the reading of my external spl or the one that shows in the rew db spl box on the left 


Alain


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## JohnM (Apr 11, 2006)

apilon said:


> one question that just pop my mind i set the spl at 75db as per the help file instruction but when i do the rew spl calibration which figure do i enter in the box before pressing done the reading of my external spl or the one that shows in the rew db spl box on the left


Enter the reading on the external SPL meter


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## JohnM (Apr 11, 2006)

apilon said:


> ok ...so there is someting that i am not doing right here then because when i followed the instructions for measurement it said set target level so i press set target level button it came up with a target of 75db then i pressed atomatic measurement so am missing something between setting up target level and automatic measurement???


Once you have re-checked the calibration of the REW SPL meter try measuring again, but first remove your house curve - as you are finding the sub is already loud enough relative to the mains you don't need to allow for any additional boost. You may then find that some of the peaks I indicated above are higher than the target curve and will come in for correction.


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## brucek (Apr 11, 2006)

> I followed some instruction from another HT forum for setting up my sub volume at half point phase a zero and crossover at the highest settings then set the crossover point in the receiver at 80


Correct. Your receiver doesn't seem to be reducing the sub level above the crossover too well though. Nothing you can do about that except filter some of it away I suppose.



> ok ...so there is someting that i am not doing right here then because when i followed the instructions for measurement it said set target level so i press set target level button it came up with a target of 75db then i pressed atomatic measurement so am missing something between setting up target level and automatic measurement???


In the end, no matter what level you choose, if the measured data is below the target you see on the graph, then REW will not see it as an area to recommend a filter for.

Personally, I like to set up the measurement level to 80dB (even though REW says 75dB), because it centers the needle on the RS SPL meter. 
In fact, when you read the little pop-up when doing the Input Volume setup, you'll see REW alludes that 80dB is better for the RS meter (even though it didn't in the Measurement Level pop-up. At a 80dB setting on an RS Meter, you can hardly read 75dB accurately. 80dB is centered.

See the pic below:










So, set everything to 80dB. Then of course if you add a large house curve, again the level may be too low. At that point I have simply manually lowered my target level after the Automatic Measurement to get more of my response above the target line, so REW will recommend more filters for me. 

brucek


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## JohnM (Apr 11, 2006)

brucek said:


> In fact, when you read the little pop-up when doing the Input Volume setup, you'll see REW alludes that 80dB is better for the RS meter (even though it didn't in the Measurement Level pop-up. At a 80dB setting on an RS Meter, you can hardly read 75dB accurately. 80dB is centered.


The 80dB in that case refers to the meter scale, i.e. use the 80dB scale (so that 75dB is at -5) rather than the 70dB scale (where 75dB would be at +5). Reason is that the meter does not have a lot of output headroom, if you were to use the 70dB range and measure at 75dB the meter would saturate internally from the slightest room peak. Even using the 80dB range and 75dB measurement level a very big peak can take the meter into saturation, hence the recommendation for 75dB measurement level using the 80dB meter scale to give some headroom. When using the meter to check a level rather than make REW measurements it can be set to the 70dB scale to make the reading then put back to the 80dB scale for the measurements.


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## apilon (May 18, 2006)

JohnM said:


> Once you have re-checked the calibration of the REW SPL meter try measuring again, but first remove your house curve - as you are finding the sub is already loud enough relative to the mains you don't need to allow for any additional boost. You may then find that some of the peaks I indicated above are higher than the target curve and will come in for correction.



John Thanks for the patience and the help just so i understand 

once i set the target level , are you saying that i should press the calibrate button to recalibrate the SPL prior to take measurement???


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## apilon (May 18, 2006)

brucek said:


> Correct. Your receiver doesn't seem to be reducing the sub level above the crossover too well though. Nothing you can do about that except filter some of it away I suppose.


Prior to redoing the EZ EQ on the AVR 635 which i done manually this time i had the AVR 635 done it automatically and it set the sub crossover at 120 so do you think i should set all speakers to 80 and the sub at 120 maybe that would take care of the roll off problem what do you think 





brucek said:


> In the end, no matter what level you choose, if the measured data is below the target you see on the graph, then REW will not see it as an area to recommend a filter for.
> 
> Personally, I like to set up the measurement level to 80dB (even though REW says 75dB), because it centers the needle on the RS SPL meter.
> In fact, when you read the little pop-up when doing the Input Volume setup, you'll see REW alludes that 80dB is better for the RS meter (even though it didn't in the Measurement Level pop-up. At a 80dB setting on an RS Meter, you can hardly read 75dB accurately. 80dB is centered.


Actually i was thinking of using the same recommended level as Avia 85db ...........but as John Suggest maybe my house curve is the problem i will try without one and see ........and as per REW instruction the SPL range was setup at 80db and the receiver volume raised until the meter read 75db


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## JohnM (Apr 11, 2006)

apilon said:


> once i set the target level , are you saying that i should press the calibrate button to recalibrate the SPL prior to take measurement???


You only need to do the calibration once, it is then OK for all subsequent measurements unless you change the input volume setting.


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## brucek (Apr 11, 2006)

> use the 80dB scale (so that 75dB is at -5) rather than the 70dB scale


Fair enough, that makes sense. I always felt when the needle was centered there was ample room on either side for dips and peaks. Then if the needle pegged on a peak, the filter I entered at that frequency would bring down the peak so the next attempt would be within the plus minus range of the centered needle. Kind of an iterative thing. I guess I'll stop recommending 80dB then.



> i had the AVR 635 done it automatically and it set the sub crossover at 120 so do you think i should set all speakers to 80 and the sub at 120 maybe


The processor crossovers for all your speakers and sub should be set to 80Hz.....
If the subwoofer itself has an integral crossover, it should be bypassed or set to maximum.

brucek


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