# back for more - full range this time



## wackii (Jul 13, 2006)

Hi all,

I want to attempt to calibrate my main speakers this time around. I had successfully calibrated my sub (flat to 13hz) about 2.5 years ago. I've just did some reading these last few days and decided to use REW to calibrate my main speakers this time. I understand that I need some thing better than the RS sound meter for full range. The ECM8000 mic seems to be the best candidate for me since I've already have a mixer, Alesis MultiMix8. I have few questions though.

1. The Alesis Mixer have 3 eq knobs (hi, mid, lo). What level should I set them at? Should I turn them all down, set it in the middle, or at max? It also has 2 effects knobs (pre, post) where should I set them at? Should I turn off all the eq and/or effects on the mixer?

2. I do have a different mic that I use to sing Karaoke. Can I use that mic for this job? The mic is Sennheiser E835. My guess is no since I need the calibration file? Just want to throw it out here for the pros.

3. Can the BFD DSP 1124P use for calibrating the main speakers? Currently I'm using it to eq my sub. I might need one more for the mains unless you guys recommend something else (less than $100).

4. Do I need to measure one speaker at a time or I need to run both speakers on?

5. Hook-up wise, do I need to run the cable directly to each speaker line-in during the measurements? Or I can just plug it to the AUX line-in?

Sorry for so many questions. I just want to clear things up a bit.

Thanks.

Al,


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

Hi Al,



> 1. The Alesis Mixer have 3 eq knobs (hi, mid, lo). What level should I set them at? Should I turn them all down, set it in the middle, or at max? It also has 2 effects knobs (pre, post) where should I set them at? Should I turn off all the eq and/or effects on the mixer?


Set the EQ knobs straight up. You don’t want them influencing speaker response. Better yet, use the Aux A send for your testing. It will totally bypass the EQ section. Don’t forget to run your calibration routine between the line input and the Aux A output. And make sure your receiver's tone controls are bypassed, too.

Re the Aux outputs: In a recording setting,they could be used as a separate mix for a recorder, while the main mix would be for the monitoring system. In a live situation, the Aux sends are typically used for stage monitor mixes. For REW they generally have no use, but as I mentioned, since Aux A does bypass the EQ section, it might be better suited for the job.




> 2. I do have a different mic that I use to sing Karaoke. Can I use that mic for this job? The mic is Sennheiser E835. My guess is no since I need the calibration file?


A calibration file is needed for any mic used.



> 3. Can the BFD DSP 1124P use for calibrating the main speakers? Currently I'm using it to eq my sub. I might need one more for the mains unless you guys recommend something else (less than $100).


Most feel the BFD isn’t clean or quiet enough for full-range use, but feel free to experiment for yourself. The consumer-level setting (switches on the back) reduce background noise, so that’s probably the setting you’ll want to use. There’s no such thing as a good equalizer for under $100. Maybe a used vintage pro audio model, but nothing new.



> 4. Do I need to measure one speaker at a time or I need to run both speakers on?


 If you don’t get the mic situated at a perfect equidistance between the two speakers, you can get comb filtering, due to the inexact time alignment. So, it’s best to test one at a time. If you have a dedicated room with symmetrical “shoebox” dimensions, then it’s sufficient to measure only one of the speakers. Any EQ needed will be relevant to the second speaker. If your room is asymmetrical (like maybe a family room with openings all over the place), then take separate readings of the two speakers. You’ll get the best results with the mic pointed at the speaker, less than 45˚off axis. If you point the mic too far off axis, the graphs will show reduced high frequency response.

You might want to take a look at this thread about full-range equalization. It has tips on how to measure, interpret the results, and how to tell a good equalizer from a questionable one.


http://www.hometheatershack.com/forums/rew-forum/6691-my-first-rew-please-chime.html




> 5. Hook-up wise, do I need to run the cable directly to each speaker line-in during the measurements? Or I can just plug it to the AUX line-in?


 Which cable? Not sure what you mean “speaker line in.” Just connect things the same way you did for your first REW calibrations.

Regards,
Wayne


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## wackii (Jul 13, 2006)

> Most feel the BFD isn’t clean or quiet enough for full-range use, but feel free to experiment for yourself. The consumer-level setting (switches on the back) reduce background noise, so that’s probably the setting you’ll want to use. There’s no such thing as a good equalizer for under $100. Maybe a used vintage pro audio model, but nothing new.


Thanks for the help. What is a good equalizer for full range speakers? Something that won't burn my pocket. If possible, can you list me a few decent equalizer?

Thanks.

Al,


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## weverb (Aug 15, 2008)

*Yamaha YDP2006*

http://www.yamaha.com/yamahavgn/CDA...00%26VNM%3DLIVE%26AFLG%3DY%26LGFL%3DN,00.html

*Rane PE17*

http://www.rane.com/pe17.html

*Symetrix 551E*

http://support.symetrixaudio.com/s.nl/sc.7/category.44/ctype.KB/KB.4374/.f

:nerd:


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## wackii (Jul 13, 2006)

weverb said:


> *Yamaha YDP2006*
> 
> http://www.yamaha.com/yamahavgn/CDA...00%26VNM%3DLIVE%26AFLG%3DY%26LGFL%3DN,00.html
> 
> ...



Thanks weverb. I've just double checked. All these are discontinued. Most stores don't have them anymore. I'll keep an eye out for used products. Thanks.

Al,


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## weverb (Aug 15, 2008)

Here is a good source for used YDP's:

http://www.saviusa.com/equipment_sales.html

Ask for Shawn and tell him Bryan sent you. He will send pictures and do testing before sending you a unit. I purchased my last two from him.

Ebay has two Rane PE 17's listed right now.

There is also an Ashley eq for sale. Wayne has recommended these in the past. I have not tried one on my highs though. It is a one channel, which could work for a center channel. I would look for the 2 channel version.

http://cgi.ebay.com/ASHLY-PQ-16-Six...3286.c0.m14&_trkparms=66:2|65:1|39:1|240:1318

There is also the XTA DP202. No one has tried it, but it looks to be a good unit. There is a single channel version also (DP100).

There is also the Sabine ADF4000. It can be controlled by a laptop or manual. I tried a different Sabine eq on my rear channel and was getting some noise. When I tried it on my subs, it was quiet. The ADF4000 may be different though.

Wayne is the best source though for eq recommendations. Let's see what else he recommends.


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## wackii (Jul 13, 2006)

Great... Thank you Bryant.

One more question, what is the different between the Rane PE-15 compared with the Rane PE-17... From what i've read, they are both 5 bands Parametric EQ... 

Thanks.

Al,



weverb said:


> Here is a good source for used YDP's:
> 
> http://www.saviusa.com/equipment_sales.html
> 
> ...


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## weverb (Aug 15, 2008)

wackii said:


> One more question, what is the different between the Rane PE-15 compared with the Rane PE-17...


Stay away from the PE15. It has been proven to introduce a lot of noise into a system. It is not good for highs.


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## wackii (Jul 13, 2006)

weverb said:


> Stay away from the PE15. It has been proven to introduce a lot of noise into a system. It is not good for highs.



Thanks for the heads up... I was able to find 2 on craigslist for cheap... Anyway, I will try to measure my speakers first then will see if I need some eq... my receiver got some eq built in as well...

Thanks.

Al,


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## weverb (Aug 15, 2008)

Be careful. This could happen to you! Thanks to Wayne's bad influence. :bigsmile:




:dumbcrazy:


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

Wow, first time I ever saw tennis balls as part of a home theater set-up. :laugh:

Regards,
Wayne


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## weverb (Aug 15, 2008)

Wayne A. Pflughaupt said:


> Wow, first time I ever saw tennis balls as part of a home theater set-up. :laugh:
> 
> Regards,
> Wayne


They are good for additional 3dB! :dumbcrazy:

Actually they help keep the two separated so they do not get too hot. I am still researching different locations for all of them. Obviously it has to be WAF approved. :sad2:


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## wackii (Jul 13, 2006)

I sat down today and got some measurements done. After more than 2 years, my FR has changed... It wasn't as smooth as before but decent I think. I have added a few furnitures and moved the sub in a lil to make room... There wasn't a major thing I needed to do on BFD. I added 4 filters and I think it's good enough... Unless, you guys see it differently... Here are the graphs:

Sound card calibration pix.









Subwoofer xover 80hz graph with 4 filters (20hz -3db, 27hz -4db, 41hz -4db, 63hz +6db). 









Same thing in waterfall. It looks like bottom heavy. Should I minus the gain on BFD a lil more?









Full Range up to 5k hz since my RS analog meter isn't accurate beyond that.









Waterfall.









All graphs are without smoothing... Any pointers? Please let me know.

Thanks.

Al,


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## wackii (Jul 13, 2006)

Are those the three YDP2006? You're probably in audio heaven with those toys. The sound must be well balanced:T I want to hear a before and after EQ. I've been looking for stores that can demonstrate a before and after EQ but can find none. Most stores are just into selling you big name brand items and never/seldom go into details like eq stuffs... 

Oh by the way, great invention on those tenis balls. They must be rattle-free due to the ball absorption :bigsmile:



weverb said:


> Be careful. This could happen to you! Thanks to Wayne's bad influence. :bigsmile:
> 
> 
> 
> ...


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## weverb (Aug 15, 2008)

wackii said:


> Are those the three YDP2006? You're probably in audio heaven with those toys. The sound must be well balanced:T I want to hear a before and after EQ. I've been looking for stores that can demonstrate a before and after EQ but can find none. Most stores are just into selling you big name brand items and never/seldom go into details like eq stuffs...
> 
> Oh by the way, great invention on those tenis balls. They must be rattle-free due to the ball absorption :bigsmile:


Yup, those are the YDP's. :yes:

I must say that my set-up has never sounded so good. I can tell the biggest difference when listening to music. On movies, the center blends much better now. I am still trying to deal with the cabinet placement. I may move it in the future though.

The tennis balls have helped mostly with heat. The YDP's did not like resting on one another. I think the biggest contributor to the heat problem is having them stuffed in the cabinet. They cannot breathe. I have to leave the door open a couple inches while listening. The third one has not gotten hot sitting in its test/current location.

As for your graphs, you look to be a little "bloated" in the 80-100Hz range. Can we see the full range plot (fourth one down) with 1/3 octave smoothing applied?


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## t6902wf (Nov 14, 2008)

I read briefly about the YDP2006. Why do you need three?
Sub, center and mains?


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## weverb (Aug 15, 2008)

t6902wf said:


> I read briefly about the YDP2006. Why do you need three?
> Sub, center and mains?


One YDP for left and right rear channels.
One YDP for center and subs.
One YDP for left and right mains.

Total of three. :bigsmile:

The fourth eq (Symetrix 551E) is for <20Hz. tuning. :dumbcrazy:


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

wackii said:


> All graphs are without smoothing... Any pointers? Please let me know.
> 
> Subwoofer xover 80hz graph with 4 filters (20hz -3db, 27hz -4db, 41hz -4db, 63hz +6db).


Hard to judge the effectiveness of your EQing without a baseline graph.



> Same thing in waterfall. It looks like bottom heavy. Should I minus the gain on BFD a lil more?


No, it’s fine. It’s common to have long decay times at the lowest frequencies. EQing that to make the waterfall look good will wipe out your excellent extension.



> Full Range up to 5k hz since my RS analog meter isn't accurate beyond that.


Full range graphs typically need to be smoothed. Try 1/3-octave smoothing.



> Waterfall.


Typically no good reason to waterfall above the bass frequencies or perhaps lower midrange.

Regards,
Wayne


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## wackii (Jul 13, 2006)

Here is the graph with 1/3 smoothing.










There is the graph before eq. I forgot to save the measurement data. Only got the image saved.









Thanks.

Al,


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## weverb (Aug 15, 2008)

wackii said:


> Here is the graph with 1/3 smoothing.


I will let Wayne give you his official thoughts. I still think the 75-100Hz area looks too high compared to the rest. The one thing that I see that may help with the highs is the 375-500Hz dip. I am not sure if it is wide and deep enough though. There also may be an over sag between 200-1,000Hz. compared to the lows and the 1k-5K area. But let's wait and see what Wayne says.


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

Basically I agree with weverb. The ~85 Hz hump is probably audible and should be tamed.

It's hard to tell since the graph stops at 5 kHz, but overall the mains seen to exhibit a gradual rise from ~200-5kHz. Most likely this is going to make the mains sound thin or shrill. The overall trend for the mains should be flat, or perhaps a gradual decline, in order to sound natural. You might want to take a look at Part 2 of my house curve article (there's a link to it in my signature). Fortunately, this would be easily to fix with the receiver's basic tone controls.

Regards,
Wayne


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## wackii (Jul 13, 2006)

Yeah, It does look like I need to tame that 80-100hz region. Since the crossover is at 80hz, that region falls on my main speakers. Maybe I should move the crossover up to 100hz and re-measure the FR. If it still there then I can tame that using my BFD (hooked with the sub). A little more details info about my setup.

I'm running 5.1 system.
* sub is huge port (LLT)
* 3 diy front speakers and two small monitor as surrounds.
* receiver = pioneer 1014 (can't remember the exact model)
* all my speakers are plugged in the emotive amp = LPA 7 channels amp
* room are about 3000 cu feet = living room + kitchen
* current parametric eq = BFD1124
* using RS analog SPL meter
* mostly watch movies more than music (most of the time I like watching concerts dvd)

Hope this extra info can help you guys understand more about system. I'll see if I have some time to measure it again with different xover. I'll post some more graph soon 

Thanks for the help guys.

Al,


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## thewire (Jun 28, 2007)

wackii said:


> Yeah, It does look like I need to tame that 80-100hz region. Since the crossover is at 80hz, that region falls on my main speakers. Maybe I should move the crossover up to 100hz and re-measure the FR. If it still there then I can tame that using my BFD (hooked with the sub). A little more details info about my setup.
> 
> I'm running 5.1 system.
> * sub is huge port (LLT)
> ...


I have the same problem and near the same size room. Using the BFD and setting the crossover higher should help a great deal.


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## wackii (Jul 13, 2006)

I got some measurements done tonight. I've noticed something is off with the xover on my reciever. See graphs below:

Subwoofer graph at crossover 100hz with no eq. From what I see, I think the xover is actually at 68hz and not 100hz (dip on that region). The peak is in 80-100hz region. I did try to tame down the subwoofer on that region 80-100hz. But my filter take no effect so I think the xover isn't really at 100hz but lower. Also, I tried to add some gain on 65hz region. Again nothing changed on that filter.









Subwoofer graph xover at 150hz. (Blue = no eq, Red = eq). Noticed the 80-100hz has dropped down a bit. Noticed the 65hz filter is improved this time.









Subwoofer graph 150hz xover with eq and smoothing. It looks like I got myself a house curve 









Full Range xover 150hz with eqs through receiver. I manually set eq at 125hz, 300hz, 4k, 13k. 
Light green orange = final eq; dark purple = no eq through receiver; bright purple = eq through receiver.









It looks like I got some positive progress through eqing from the receiver  Fortunately, I can't localize the bass even though my crossover is at 150hz (probably off on receiver). I only have time to listen for about 15 mins though. I need to put some time listening to my system to see if the crossover at 150hz is suitable. Other than that the graph looks better 

Al,


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## thewire (Jun 28, 2007)

That looks so much like the response I had from last month besides bellow 25Hz I am amazed. I moved the mains further from the seats and closer to the side walls, then checked phase, adjusted speaker distances.. The 80Hz crossover is a bit like having stereo subs and can be a bit distracting. I thought 100Hz was alright but 150Hz was really eating into my subs headroom. Are you aiming your mic directly up?


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## wackii (Jul 13, 2006)

thewire said:


> That looks so much like the response I had from last month besides bellow 25Hz I am amazed. I moved the mains further from the seats and closer to the side walls, then checked phase, adjusted speaker distances.. The 80Hz crossover is a bit like having stereo subs and can be a bit distracting. I thought 100Hz was alright but 150Hz was really eating into my subs headroom. Are you aiming your mic directly up?


No, my mic is at 45 degree angle. Does the mic angle effect the measurements in full range? I agree about the 150hz crossover eating into sub's headroom. But I have a feeling that the crossover setting on my receiver is off. Is there a way to measure the crossover on my receiver? I remember reading some threads here showing that the his receiver's crossover was off as well. About my mains, there's really not enough room to move further back to the wall. I want the front baffle of my mains to be the same level as my tv. 

Thanks for your inputs.

Al,


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## weverb (Aug 15, 2008)

brucek told me something like this for testing xo:

http://www.hometheatershack.com/forums/rew-forum/12622-rew-noob-5.html#post115700

Don't know if it will help. :huh:


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## thewire (Jun 28, 2007)

weverb said:


> brucek told me something like this for testing xo:
> 
> http://www.hometheatershack.com/forums/rew-forum/12622-rew-noob-5.html#post115700
> 
> Don't know if it will help. :huh:


To test my crossover I input White Noise into the input I am looking at with the crossover on, and use the Spectrum Anylizer with no calc file loaded and the output of the receiver, media player, directly into the input of REW and see what happens. I calibrate using a sine wave of -20dB FS. You may have to note that -2dB FS is 0dB FS in REW. It should not read that high anyway. I used this to test some amps pass through etc also. It might not hurt to burn a CD with the Generator also and test the source input and outputs if they are different than what you use view movies, listen to music etc.

The White Noise should track the crossover slope, or the 12dB Octave one if using that, on the filters tab window.


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## wackii (Jul 13, 2006)

weverb said:


> brucek told me something like this for testing xo:
> 
> http://www.hometheatershack.com/forums/rew-forum/12622-rew-noob-5.html#post115700
> 
> Don't know if it will help. :huh:



Thanks for the link. I will give that a test.

Al,


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## wackii (Jul 13, 2006)

thewire said:


> To test my crossover I input White Noise into the input I am looking at with the crossover on, and use the Spectrum Anylizer with no calc file loaded and the output of the receiver, media player, directly into the input of REW and see what happens. I calibrate using a sine wave of -20dB FS. You may have to note that -2dB FS is 0dB FS in REW. It should not read that high anyway. I used this to test some amps pass through etc also. It might not hurt to burn a CD with the Generator also and test the source input and outputs if they are different than what you use view movies, listen to music etc.
> 
> The White Noise should track the crossover slope, or the 12dB Octave one if using that, on the filters tab window.



Sorry, I'm totally lost.

Al,


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## brucek (Apr 11, 2006)

> No, my mic is at 45 degree angle. Does the mic angle effect the measurements in full range?


The mic is calibrated such that the vertical position is best when placed at the listening position.



> But I have a feeling that the crossover setting on my receiver is off. Is there a way to measure the crossover on my receiver?


Absolutely.

When you connect a loopback cable from line-in to line-out of your soundcard and take a measurement, it will return a perfectly flat line (as long as your soundcard cal file is loaded and the meter cal file is cleared).

Since your receiver is a line-level device, you can connect it into that loopback and take a measure of it to graph its response. You feed the soundcard line-out to the receivers CD or AUX in and then connect the receivers sub out jack to the soundcard line-in. Now take a measure (you have to fuss a bit with the receivers volume control to get the Check Level routine correct). That's it.

brucek


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## wackii (Jul 13, 2006)

Thank you Bruce, Weverb and thewire. I got the crossovers measured today. Nothing against you thewire, your instructions are a little more confusing. I'm using Bruce's instruction and it came out nicely. See my graphs below. This is for my Pioneer VSX-1014TX receiver.

Crossover graphs for sub at 50, 80, 100, 150 and 200hz from left to right.









Crossover graphs for mains at 50, 80, 100, 150 and 200hz from left to right.









Crossover graphs from mains and sub together at 50, 80, 100, 150 and 200hz (missing 200hz crossover for main. REW only allows me to combine 9 measurements)









I found something interesting about my mains when I measured them without the sub turned on. It seems like my mains have the peaks at 80-100hz regions. Setting different crossovers do help in this case. That explains why when I set the crossover at 150hz, that region dropped. It looks like the best crossover for me is 150hz due to my main speakers have peak at region of 80-100hz.









Here is my full range measurements with some of the built-in eq on receiver. BFD eq is on as well for the sub.









Welcome any inputs to improve my system.

Thanks.

Al,


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## weverb (Aug 15, 2008)

I think it is time for you to get the ECM8000. :bigsmile: If you really want an accurate picture of what your mains are doing, that is the best way to go. You will be surprised by the difference between the RS meter and the ECM8000.


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## wackii (Jul 13, 2006)

weverb said:


> I think it is time for you to get the ECM8000. :bigsmile: If you really want an accurate picture of what your mains are doing, that is the best way to go. You will be surprised by the difference between the RS meter and the ECM8000.


I think so too. Right now, I'm basically guessing on my mains FR. It might be good up to 3k and might not be. 

Al,


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## thewire (Jun 28, 2007)

I have been trying to basicly follow savasol's setup and recall how he dealed with problems in the front of the room. I have also been trying to take what knowledge I have of far field versus near field and apply that. Sitting furthur from the speakers (better than 8.5' far is considered best I read) and moving the subs, some acoustic panels, adjusting the seating I was able to address the crossover area at least some. As I have read, this comes up often. Here is an example of my progress so far in trying to experement and see what improvements I can gain. The 400Hz area and above is effected by my book shelves.

http://farm4.static.flickr.com/3432/3218940949_54df03bbcf_o.jpg

It was espicially difficult to address the subwoofers locations however, and they had some gain in areas around 80Hz more that I had to equalize. I went for a 30Hz instead of 25Hz because I am dealing with a couple things I wanted to try at once. If you have not tried moving the seating and you can, it may be worth trying.:dunno:


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

> I found something interesting about my mains when I measured them without the sub turned on. It seems like my mains have the peaks at 80-100hz regions. Setting different crossovers do help in this case. That explains why when I set the crossover at 150hz, that region dropped. It looks like the best crossover for me is 150hz due to my main speakers have peak at region of 80-100hz.


You might try setting your sub's crossover separately to 80 Hz or so. That would give you an underlap that may well flatten out that region.

Regards,
Wayne


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## wackii (Jul 13, 2006)

Wayne A. Pflughaupt said:


> You might try setting your sub's crossover separately to 80 Hz or so. That would give you an underlap that may well flatten out that region.
> 
> Regards,
> Wayne


Hi Wayne, unfortunetly my sub amp is a pro amp. It doesn't have a crossover buillt in. It's an QSC RMX 850. I think that region is cost by the main speakers. Even at 100hz crossover, it still has that peak. That region drop almost 10db if the crossover is at 150hz.

Thewire, I can't really move my sub or mains due to the size of my speakers. I'm seating about about 11 feet away from the mains and about 7 feet away from the sub. Too bad there isn't much space left for me to move the speakers around.

Thanks.

Al,


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

wackii said:


> Hi Wayne, unfortunetly my sub amp is a pro amp. It doesn't have a crossover buillt in. It's an QSC RMX 850. I think that region is cost by the main speakers. Even at 100hz crossover, it still has that peak. That region drop almost 10db if the crossover is at 150hz.


Well, that just shifts the problem region down to the sub, which means it'll be what's generating it. In theory, that is. It would be pretty unusual if you got it only from the main speakers, because typically it's a room issue, not a speaker issue...

Regards,
Wayne


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## wackii (Jul 13, 2006)

Wayne,

I've just realized about the shelf filter on your house curve article. Do you think it's a good idea to place a shelf effect filter cutting 10db at 360hz of 2 octave to pull down that region on my subwoofer? Right now, I only have 4 filters for my subwoofer. 

Thanks.

Al,


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## brucek (Apr 11, 2006)

> Crossover graphs for sub at 50, 80, 100, 150 and 200hz from left to right.


Wackii, you had the C-Weight box or the meter calibration file loaded when you did these measurements which renders them somewhat invalid. You must clear the C-weight box and have no meter cal file loaded to do a test such as this (just as they must be clear when you measure a cable loopback to render a straight line).

Fortunately, you don't have to remeasure. You can simply load the saved mdat file and then clear the C-Weight box and meter cal file, then select a measurement and click the IR Windows button (top right corner REW) and then press Apply, and the measurement will be corrected. Do it for each measurement.

brucek


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## wackii (Jul 13, 2006)

brucek said:


> Wackii, you had the C-Weight box or the meter calibration file loaded when you did these measurements which renders them somewhat invalid. You must clear the C-weight box and have no meter cal file loaded to do a test such as this (just as they must be clear when you measure a cable loopback to render a straight line).
> 
> Fortunately, you don't have to remeasure. You can simply load the saved mdat file and then clear the C-Weight box and meter cal file, then select a measurement and click the IR Windows button (top right corner REW) and then press Apply, and the measurement will be corrected. Do it for each measurement.
> 
> brucek


Bruce, you are right. I forgot to uncheck the C-Weight box. Here is the new graph.











Sub and mains graphs with C-Weight correction. 









Thanks.

Al,


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## brucek (Apr 11, 2006)

> But I have a feeling that the crossover setting on my receiver is off.


So, I guess we can put that notion to bed.....

Isn't it amazing that we send that perfect signal to a speaker, and then we let it loose in the room and it does such damage to it. The room is everything.

brucek


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## wackii (Jul 13, 2006)

brucek said:


> So, I guess we can put that notion to bed.....
> 
> Isn't it amazing that we send that perfect signal to a speaker, and then we let it loose in the room and it does such damage to it. The room is everything.
> 
> brucek


At first, I thought the receiver's crossover is off. After seeing the signal, the room is my problem. I think I need to move something around but with a huge sub and a big couch, there isn't much to move.

Al,


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## wackii (Jul 13, 2006)

Wayne A. Pflughaupt said:


> Hi Al,
> 
> Set the EQ knobs straight up. You don’t want them influencing speaker response. Better yet, use the Aux A send for your testing. It will totally bypass the EQ section. Don’t forget to run your calibration routine between the line input and the Aux A output. And make sure your receiver's tone controls are bypassed, too.
> 
> Re the Aux outputs: In a recording setting,they could be used as a separate mix for a recorder, while the main mix would be for the monitoring system. In a live situation, the Aux sends are typically used for stage monitor mixes. For REW they generally have no use, but as I mentioned, since Aux A does bypass the EQ section, it might be better suited for the job.


I got the ECM8000 delivered to me today. I'm now ready to do some measurements :yay: I do have some questions regarding the cables hook-up. 










As shown above, do I set everything like that? All I need is to adjust the main mix level to calibrate my mic to 75db? Am I on the right track? 

Thanks for the help.

Al,


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## brucek (Apr 11, 2006)

> As shown above, do I set everything like that?


The PAN can be dialed to prefer the channel used (fully CW). I dial the other channels to off.

AUX isn't the main line-out. The MAIN MIX is.

Center the two channel gains, and use the Main Mix to control level.

brucek


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

The pan control moves the signal between the left and right channels, just like the balance control on a receiver. Straight up sends it equally to both channels.

As I noted before, using the AUX output should bypass the EQ and HPF. The only caveat: Most mixers have a master AUX "send" knob to adjust the level of all the AUX settings (it's a different thing than the AUX "return"). This mixer doesn't have an AUX "send," so I'm not sure how that function is being accomplished (I've had my Multimix for a couple of months now, but I haven't used it yet). You might be better off just using the Main outputs instead of the AUX send and making sure the EQ settings are flat.

By the way, if you find that the level knob for the channel strip (i.e. just below the Pan knob) changes the level of the AUX output, then all bets are off - it doesn't bypass the EQ and HPF. If that's the case, there's no good reason to use the AUX out.

Regards,
Wayne


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## wackii (Jul 13, 2006)

I did some measurements today with the new ECM8000. I loaded the splitecm.cal file, remeasured the soundcard cal file. Everything went smooth. See my graph below.

Crossover is at 100hz. There's no eq apply on this graph. It looks like I need lots of work at 150hz to 1.5khz region, also 8khz to 20khz is a pretty steep drop. Any recommendations on how can I attack this?









This graph is the individual speaker with sub turned on. Left main speaker is green, right main speaker is orange.









Purple is with both speakers on + sub (combo of all 3 measurements).









Thanks.

Al,


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

> There's no eq apply on this graph. It looks like I need lots of work at 150hz to 1.5khz region, also 8khz to 20khz is a pretty steep drop. Any recommendations on how can I attack this?










Either by moving the speakers around, or EQ. If your receiver has some quasi-parametric tone controls that will let you center on 4-500Hz, you might be able to a minor adjustment.

Regards,
Wayne


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## wackii (Jul 13, 2006)

Wayne A. Pflughaupt said:


> Either by moving the speakers around, or EQ. If your receiver has some quasi-parametric tone controls that will let you center on 4-500Hz, you might be able to a minor adjustment.
> 
> Regards,
> Wayne



Wayne, thanks for your inputs. My receiver doesn't let me adjust anything that range  I can only add some eq at 40hz, 125hz, 250hz, 4khz, and 13khz. Maybe I can use the BFD1124 to do some eq and hopefully it won't produce any noise. There's not enough room for the speakers to move around. I'll take a pic or two of my room to see if there's any improvements can be done.

Thanks.

Al,


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

> Maybe I can use the BFD1124 to do some eq and hopefully it won't produce any noise.


You'll need outboard amplification in order to EQ the mains (or pre-out/main-in jacks on your receiver).

Regards,
Wayne


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## wackii (Jul 13, 2006)

Wayne A. Pflughaupt said:


> You'll need outboard amplification in order to EQ the mains (or pre-out/main-in jacks on your receiver).
> 
> Regards,
> Wayne


I got ext amp, Emotiva LPA-1. It's a 7 channels amp of 125W/channel. Thanks.

Al,


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## weverb (Aug 15, 2008)

I will be surprised if the 1124P works out ok on your mains. Also, let's see some pix of your set-up. It is always cool to see what we are dealing with. :bigsmile:


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## wackii (Jul 13, 2006)

Here are the pics of my room. It's a little messy.

This shows the front setup of my system, directly behind is my kitchen.









Another one.









Here is where I seat. 









Not much space for me to play with.

Al,


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## weverb (Aug 15, 2008)

Al,

From the pictures, it looks like one of your mains in angled in more than the other. Also, I wonder if because the right main has nothing behind it versus the left, you are getting that variation. :huh: Do you have any piece of drywall/plywood or anything reflective that you can place behind the right main and remeasure?


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## wackii (Jul 13, 2006)

weverb said:


> Al,
> 
> From the pictures, it looks like one of your mains in angled in more than the other. Also, I wonder if because the right main has nothing behind it versus the left, you are getting that variation. :huh: Do you have any piece of drywall/plywood or anything reflective that you can place behind the right main and remeasure?



I can't place anything behind that right main speaker. That would block my walk way to my kitchen. I have noticed that the main is a lil angled straight compare to the left one. I will turn it a lil to match with the other speaker.

Thanks.

Al,


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## wackii (Jul 13, 2006)

I had some time to tweak my system today. I re-run my receiver auto calibration, move my coffee table a lil, clean up some junks. I think it helps a lil.

Baseline measurement with no eq 020809









Left speaker close mic measurement with no sub 020809









Right speaker close mic measurement with no sub 020809









Added the baseline measurement 020809









It looks pretty good now. There's a dip around 150hz to 200hz region. I think that cause be some sort of cancellation on the two speakers (there are not dip at all on the individual close mic measurement). Do you think eq will help on that region or I need to move the speakers and experiment with them?

Thanks.

Al,


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

The 150 Hz thing is nothing to worry about. Your baseline graph looks pretty good. :T

Regards,
Wayne


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## wackii (Jul 13, 2006)

Wayne A. Pflughaupt said:


> The 150 Hz thing is nothing to worry about. Your baseline graph looks pretty good. :T
> 
> Regards,
> Wayne


That's great. How about the region 10khz to 20khz? It looks like a big dip. Do you think I can eq that or moving the speakers might help more?


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

wackii said:


> That's great. How about the region 10khz to 20khz? It looks like a big dip. Do you think I can eq that or moving the speakers might help more?


Hard to say. There have been some issues with some mics and the calibration file that high up (i.e., they were a bit different from the one we had our file created from), so I'm not confident what you're seeing between 10-20 kHz is even an accurate reading. Don't think I'd lose any sleep over it...

Regards,
Wayne


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## weverb (Aug 15, 2008)

wackii said:


> I can't place anything behind that right main speaker. That would block my walk way to my kitchen.


Al,

I meant to place something temporarily to just see what impact it may have on your response.


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## wackii (Jul 13, 2006)

weverb said:


> Al,
> 
> I meant to place something temporarily to just see what impact it may have on your response.


I see your point. I'm currently live in an apartment. I don't have anything to test that. Thanks for the suggestion.

Al,


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## wackii (Jul 13, 2006)

Wayne A. Pflughaupt said:


> Hard to say. There have been some issues with some mics and the calibration file that high up (i.e., they were a bit different from the one we had our file created from), so I'm not confident what you're seeing between 10-20 kHz is even an accurate reading. Don't think I'd lose any sleep over it...
> 
> Regards,
> Wayne


I see. I thought the ECM8000 is accurate up to 20khz. If that's the case, I don't think I'd need an equalizer. 

Thanks.

Al,


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## brucek (Apr 11, 2006)

It is, but it also depends on some factors. Please read this entire thread.

brucek


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## wackii (Jul 13, 2006)

brucek said:


> It is, but it also depends on some factors. Please read this entire thread.
> 
> brucek



Thanks Bruce for the link. After reading that thread, I'm not sure how to place my mic (horizontally or vertically?). My measurements here, I have it horizontally. It seems like the more you find out about things, the more you're lost... strange isn't it? 

Thanks.

Al,


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## brucek (Apr 11, 2006)

> My measurements here, I have it horizontally.


As we discussed earlier in this thread, the mic should be used in a vertical position for listening position measurements.

brucek


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## wackii (Jul 13, 2006)

brucek said:


> As we discussed earlier in this thread, the mic should be used in a vertical position for listening position measurements.
> 
> brucek


Thanks. For some reason, I missed that.

Al,


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## bh48 (Mar 21, 2009)

Very interesting thread on full range EQ. I have a question. I've spent the past twenty-four hours immersed in REW, measuring my system. With my soundcard and RS meter calibrated, the overall trace follows the prediction quite nicely from 10 to 5khz, with the normal room lumps and bumps thrown in to force me to purchase a BFD and a calibrated microphone (More toys!). There is, however, a persistant 10db broad peak centered at 3.5kHz and spanning 3-5kHz. I've tried: 

1) Changing the toe-in on my speakers
2) Damping the wall behind me with a thick quilt
3) Moving the diffactors behind my chair to another room

Nothing is impacting this peak. I'm wondering if it is a measurement artifact or perhaps microphonics hitting my tubes? Any ideas you might have on whether or not this is real -- I think if it was, my system would sound very bad, and it doesn't -- and how to get rid of it, would be appreciated. 
Brad


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## brucek (Apr 11, 2006)

> There is, however, a persistant 10db broad peak centered at 3.5kHz and spanning 3-5kHz. I've tried:


It's well known that the Radio Shack meters have a peak within that region. The upper limit of measuring with a Radio Shack meter is 3KHz. Read this article
If you want to measure full range, you need a full range mic or meter.

brucek


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## bh48 (Mar 21, 2009)

Thank you Bruce for the article. Its good to know that it is a measurement artifact. Now I can sleep at night. :whew: REW -- What an excellent piece of software!! -- has gotten me back into measurement, but ears still work quite well. I've been enjoying the tips and techniques in Jim Smith's Get Better Sound for the past couple of months and was greatly surprised at how much improvement his voicing techniques made in my system. I'm looking forward to further improvements with a BFD and a calibrated mic. Brad


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