How to use test tones to calibrate

[racer4551]

All right guys i think i can do this but i need a little guidence here,i want to take a freq. response reading from my system,i have downloaded the gomer test tones and burned them to a cd,so my first question is what exact tones do you use for testing?Second,where do you take the readings from?The sweet spot or some where else?Third, do you play this tone in direct stereo mode on my receiver?I would assume yes because its recorded in two channel,my processor allows the option of using or not using the sub in direct two channel,so would it be best to take a reading without the sub to see where to set the icbm crossover for the mains(set to where then mains really trail off on spl)then bring the sub in to the mix.Or should i just set the crossovers all to 80 and the sub freq. to max,which is where i have them now.Thats it for now ,but what to do with all the readings taken as far as applying them to a graph is the next step i will need help with.Any help would definatley be appreciated.

[gatemplin]

I use all of the tones and then some. I put the meter in the listening position and run the tones with the stereo speakers on as well. Dont forget to use the correction factors.

[racer4551]

Does the spreadsheet automaticaly figure the correction factors?Where do i get the spread sheet for figuring the graph?I know this has been covered before but am unsure where and which graph to use.

[gatemplin]

If you need the spreadsheet with correction factors for those test tones send me your e-mail address and I'll send it to you. PJdami made it.

After you plot the data, choose insert chart and make a line chart. If you get stuck I can help.

[racer4551]

Thanks for all the help so far gatemplin,gotta sign off for tonight,got to do that work thing tommorro,god i hate working on saturdays:mad: :mad: Will pick this up tommorro,also sent you a pm.

[gatemplin]

Just sent you the spread sheet

[racer4551]

Just ran the test tones, now how do i view these on a graph,i entered them into the spreadsheet, now what?:confused:

[Airplay355]

highlight the cells u entered info in, then click on the chart wizard icon, it is a tiny bar graph with red blue and yellow bars on the top of the screen, choose ur gaph and ur good to go

[racer4551]

How do i save this spreadsheet so i can upload to this forum,it keeps telling me its an invalid format? Wait till you see this crazy graph,either i did something wrong or i like bass to much!Now if i could only get this to upload....................

[pjdami]

racer,

Make sure you use the beyondgomer test tones that correspond to that particular spreadsheet or it will be all out of sync.

I sent ya a pm back.

Paul

[Airplay355]

when u click save as you are prolly gonna have to save the file as a jpg or some type of picture file so u can upload it to the website, try that

[racer4551]

Thats what i am having trouble doing,saving as a file that can be uploaded.I did use the gomer test tones. Working on how to save as i type this?...........................................

[Airplay355]

u can copy and paste the chart into a program like photoshop and save it as a picture there....idk if thats the best way to do it but it works

[racer4551]

Still trying...............about to give up:mad: :mad: :mad: any of the programs i have will not recognize the spreadsheet because its not a photo?Damn computers! why do they have to be smarter than me:( :( :(

[pjdami]

Racer,
Open up the spreadsheet and go to the chart (graph) worksheet. Now in the upper left corner of the graph left click to select the entire chart. You should see some small squares around the entire chart letting you know it is selected.

OK. Now go to the top menu bar and click Edit > copy to copy the graph.

Open up whatever program your computer uses to look at pictures. I'm using Windows photo and fax viewer. Click file > new in the menu bar and then edit > paste. Save as a .jpg file.

You will then need to make sure that the picture is smaller than 100 kb which is somewhere near the max size that Polk allows to post. You may need to edit the picture sized by the stretch feature.

If you are still having trouble let us know what program you are using to look at pictures.

[racer4551]

Finally!!!!!!!!Thanks pjdami,how simple was that!!!!Have a very bad headcold last couple of days and have been living in a fog,so thanks for the patience .Well here it is,what a mess ,i have the sub calibrated a little hot for low level response,on avia setup it is about ten db's higher than other speakers.I have the sub level set to -5 at processer and 0 at icbm sub level control and 12:00 position on svs gain .

[gatemplin]

Youch!

So the ICBM is doing the bass management. Where is the crossover freq?

Maybe adjusting the Phase and crossover frequencies can flatten that out. Try a couple more plots.

[racer4551]

Yes the icbm is doing all the bass management right now,i have all the x-overs set at 80, i havent messed with the phase control setting ,i think its at 110 on the svs.I also made sure that my bass control was set o and treble is set to +2 on the processor.I think that i am going to recal. with avia disk just to make sure of levels,because i have changed the sub pos a little and also changed the way it was sitting(had spikes in the base,wrong thing to do,it would vibrate an dmove around on those spikes)

[racer4551]

Well i made a change of only the svs sub level gain from 12:00 pos. to the 10:00 pos,brought the level down on the graph,but still alot of peaks and valleys.I have tried to upload as before but when i do this nothing happens?Anyone have a recommendation for some imaging software that i can download or buy ,i have currently microsoft picture it! express 9 and arcsoft photobase 2.0 photo studio 2000 installed now,they were installed by a friend who built this computer and i have no disks to reinstall.I think there might be a problem with these programs?HELP!!!!!!

[gatemplin]

Right click on the chart in Excel, copy
Open Microsoft Paint in Accessories
Paste chart in Paint
You can resample size if it is too large
Save File as .jpg
Then upload

Hope this helps, this is what I do, it should work

[racer4551]

Ok i got it to display in the paint section,now how to i resize and save?

[racer4551]

Ok here is the latest graph,still ugly........................

[racer4551]

What would be the next best thing to do,adjust phase control?what would be the best procedure to do this?

[gatemplin]

To re-size go to Image and Stretch/skew

That graph is ugly, I would try making charts at 0, 45, 90, 135 and 180 degrees and picking the flattest one and fine tune from there.
I dont know enough to say whether or not that is the problem there but it couldn't hurt.

[racer4551]

Thanks very much for everyones help so far,i think thats a good place to start ,with the different phase control settings and see what that does.

[gatemplin]

Are there phase controls on both the ICBM and the SVS? Is the crossover on the SVS all the way up? maybe there is something funky goin on there.

If the phase is not the problem then I think it is location. Is it possible to move the sub to the other corner behind the LSi or move the sub out where the speaker on the floor is?

Hopefully Doc will have some suggestions aswell

[pjdami]

Racer, that's going to be a challenge with that placement. Do try what gatemplin has suggested with the phase control. Actually, I had a very similar looking curve with corner placement of my sub.

If the phase control doesn't work is there any other convenient place to put the sub? You can move it totally to the other side of your front soundstage or just move it a foot or two from where it is now. All of these will give you surprisingly different results.

It can be frustrating and very time consuming but patience and your ears will ultimately be the deciding factor.

Unfortunately, you like me, are plagued by some bad room acoustics in that position. Not everyone has this misfortune. Room placement is key to cure this.

[pjdami]

Are there phase controls on both the ICBM and the SVS? Is the crossover on the SVS all the way up? maybe there is something funky goin on there.

Yeah, gatemplin, I was thinking the same thing here. Could there be some double filtering at the crossover point going on or something.

Unfortunately, I have no advice on the operation of an ICBM as I've never messed with one.

Racer, a quick test would be just to move the sub somewhere else and run a sweep. That would give some clues as to if you are in a room null now or if it is something electronic going on with some of your settings.

[racer4551]

No phase controls on the icbm,just sub gain(set at zero) and lfe control(set at max level0)Both receiver and dvd player set to large speakers,no delay and icbm x-overs all set to 80.I can move the sub out beside left front lsi or could move to right front corner behind rf lsi.I am going to finish running the different phase control settings and see which position is best and then go from there.

[gatemplin]

It sounds like you are on the right track now. Hopefully things will flatten out. The phase settings will have to be readjusted if you move the sub though.

[racer4551]

I think i got it now,will see:D gonna see if the phase helps any with the sub in that left front corner,if not will change position to see what that does,i know i have to run the phase tests again after moving the sub,but this is so much fun!I really think in the end i will learn alot about my room effects and hopefully tame the freq curve i have.I have been wanting to do this for awhile now and have been puttting it off,so hopefully it will be worth it.As a last resort, i could also use a bfd1124 to help straighten things out,plus i have my dual channel art355 that i can use also for the mains if needed,but i want to try and do everything i can before resorting to eq's.

[racer4551]

Well i ran all the tones in the 0,45,90,135,180 phase positions and the most stable was the 180 position.Here is updated graph,still ugly...........................

[racer4551]

Still unsure whats happening in the 80hrtz to 50 htz area pretty big dip there....................gonna try moving the sub out beside the left front main tommorro then recheck everything.

[pjdami]

Racer, just noticed your system on your sig. Question for you. why are you using the ICBM if you have a Rotel RSP-1066? The Rotel should be able to handle the crossover duties right? Just curious. I had the RSX-1055 for a while last year and am familiar with the menus.

[racer4551]

I have tried it both ways ,using rotels bass management without the icbm and with the icbm,even though i have not tried using rotels bass management with the lsi's,i find that with the icbm the sub response is a lot better,blends with the other speakers more,it seemed to my ears that sub response was weak using rotels bass management?Also you are limited only to one crossover setting for all speakers in the rotel setup and when it was purchased i thought i needed the individual crossover settings to setup properly with the different surround speakers i had at that time.I am thinking about using the rotels bass management before i move the sub just to see how it effects the freq. response .

[racer4551]

Well i tried using the rotel's bass management and it didnt make any difference at all to the curve.I have this big dip i am wondering about from the test tone of 79.4 to 56.2 the level drops on average of10 to 12 spl,could this be sub placement issues?

[Tour2ma]

Have you tried changing the cross-over point? If not, run sweeps with it at 100 and at 60...

[pjdami]

could this be sub placement issues?

Could very well be. Try a couple of quick sweeps at different xovers like Tour said and then time to move it to the other side of the soundstage if you still have the null.

[racer4551]

Well i moved the sub to the right front corner,recalibrated sub level(sub is 10db higher than other speakers) sub vol 11:00 position,phase 180,icbm crossover's set all to 80..............................

[pjdami]

Looking a lot better Racer. Does it sound better? You should be able to hear a difference in reducing that huge 40 hz peak that you had?

You can definitely work with that curve if you like what you are hearing.

Paul

[Dr. Spec]

What are you calibrating with that is indicating the sub is 10 dB hotter than the other speakers?

That peak you are seeing in the 70-100 Hz region is due to the fact that the natural roll-off of the speakers in that region is not 4th order.

If you had THX certified speaks with an F3 of 80 Hz and a 2nd order natural roll-off, you would not be seeing that peak. I have the same problem.

Try enabling your low pass filter at 80 hz and see what it does to that peak.

Doc

[racer4551]

Does it sound better? pjdami,it sounds ok,used to the bass peaks,sound more mellow now,good though.set the low pass filter to 80. Dr.Spec,you mean the filter on the sub?

[Dr. Spec]

Originally posted by racer4551
Dr.Spec,you mean the filter on the sub?

Yes.....enabling the SVS low pass filter at "around" 80 hz should knock out some of that peak in the 80-100 Hz region. Give it a try.

[racer4551]

Thanks for the info dr.spec, will give that a run and see.What are you using for test tones i used my test tones in my rotel for the sound levels,have found them real close to avia,but like them better because i can get tones for the center back two speakers.

[Dr. Spec]

Hard to believe the sub is 10 dB louder. The sub level in the 35-70 Hz region is lower than the 80-100 dB region.

It would be nice to see the curve up to 200 Hz to get a better flavor for what is happening with the average speaker level from 80-200 Hz.

[racer4551]

[QUOTE]Originally posted by Dr. Spec
[B]Hard to believe the sub is 10 dB louder. The sub level in the 35-70 Hz region is lower than the 80-100 dB region[QUOTE] Yeah i am kinda confused by this also,but with the speaker levels at 75db the sub reads 86 db? Sorry for the quote notations,still trying to figure out how you post quotes?

[gatemplin]

Racer,

If you want to see what is going on above
100 Hz, burn these test tones.

http://www.snapbug.ws/sinewaves/

It isnt necessary to burn all of them, but it would give you a broader picture.

[racer4551]

Will those tones work with the spreadsheet i have now?

[gatemplin]

No, not that sheet. These tones work with the Excel sheet that you can download at Sonnie's BFD page, the link is at the bottom

http://www.snapbug.ws/bfd

I havent used it but many others have.

[racer4551]

Ok,here's the latest test sheet ,i used the snapbug tones and their excel sheet.I decided to move the sub back to the left front corner because i really like it there better,it looks better.I KNOW THATS CRAZY!!!but i would really like to make it work if it is possible in this corner.So what are my options to make this curve look a little better?Right now i have eliminated the icbm from the setup and have the rotel set to all speakers small and sub x-over set to 80,svs set to 11:00 gain position and sub x-over to 90.This was the setup for the supplied graph.I would like to try to rid the curve of those two big dips.The dark blue line is the present curve.

[gatemplin]

That is ugly, the only option with big nulls are tweaking (phase, crossover again) and location. An PEQ is amazing for peaks but you will run out of power trying to fill in nulls like that. I dont know how to fix that without moving it.

[racer4551]

Yeah that is an ugly graph huh? I have been all over the phase and crossover's to try and pick up those dips and anything i do doesnt really amount to much change in spl in those areas.I was wondering if a bfd1124 would help in this situation,sent an email with the latest graph to them to see what they recommend.If i cant pick up these dips i guess i will move the sub back to the rf corner.Whats crazy it doesnt really sound bad at all,lots of deep bass..........

[racer4551]

What is the best way to set the phase control on the svs?

[gatemplin]

You will have deep bass but you will notice things in music you know well, are missing. Like drums that dont hit as hard etc. I had a big dip at 70 Hz and was able to minimalize it with location and phase adjustments and then boost it just a couple of dBs with my BFD. I love the 1124, it can help smooth out the response but with only 16 dBs of signal boost it cant bring that graph up at the nulls.

[racer4551]

Well i finally decided to move the sub back to the rf corner,got rid of alot of those peaks,looks alot better,this chart is with the sub gain set at 11:00 position,90 phase,90 x-over.................Dark blue line is current read,dont know what that pink line is??

[racer4551]

Second graph is with sub at 180 phase,90 x-over, lost -2 db's at 45 htz,-3.5 at 50,-4 at 56htz,-1 at 63htz,+2 at 71htz,+8 ! at 80htz,+11 !!! at 89htz, +3 at 100htz,+9 !!! at 125htz, everything else stayed the same,was this a better setting?From 40htz down nothing changed.Any suggestions?.................

[gatemplin]

Much better. The pink line is Sonnie Parker's sub. Keep checking the phase and pick the flattest one.

[racer4551]

Yes ,thats with the 15's on also,i think that second move just made alot more peaks?

[gatemplin]

I changed the post when I saw the second graph. Yeah, I think the first one looks better. I could live with that. How does it sound?

[racer4551]

Yeah with the first graph settings it sounds pretty good,will go through all the phase and x-over settings on the svs and settle for the smoothest and best sounding.I have been learning alot by doing this and incourage everyone who's interested that it's well worth it in the end.I have found just by repositioning a sub you can change dramatically the sound that it outputs and how it blends with the whole setup .Letalone how much the room affects the bass quality and quanity.