# Wierd results when measuring soundcard response, need new S/Card??



## terry j (Jul 31, 2006)

Hi all, have spent the last few days reading reasonably conprehensively the posts on the forum. Don't want to waste peoples time without at least making the effort eh!

Strangely enough, in the post dated Aug 8th 2006 by Vaughan Odendaal, he describes exactly the point at which I'm stuck. (his post is at the top of page three of the forum.)

What is also very much of interest is that it is exactly the same soundcard that I'm using. At the top of page two of the post is the graph in question. Mine is pretty well the same, however my -3db points are 2.6hz and 5.544 khz. Additionally, the target RMS was-6.0 db and the actual RMS at 1 Khz was -6.0 db. Mentioned that because a later comment in the thread noted his results, presume it's valuable data.

Of course, what is annoying is that the thread just ends! aarghh

This soundcard is prob only a month old at the most, so would be mighty pee'd off if have to buy a new one ( will of course if neccessary). So, can any troubleshooting be done that will answer the question of whether or not I need a new card?

By the way, if I'm mucking up the procedure in any way, then I'd strongly suspect that it is in the computer skills area, eg the on;ly controls I can find for the soundcard is the normal windows one. So if someone were to suggest for example 'check that there is no effect switched on' I'd have no idea on where to find it!

thanks very much for your help, am quite excited and very much looking forward to using the program. Hope one day to be experienced enough with it to then be able to 'return the flow' and help others in the future.

Kind regards, and talk to you soon

terry


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## brucek (Apr 11, 2006)

Perhaps tell us the type of soundcard you have and post your soundcard cal graph.... Is the soundcard cal the area where you are having the trouble?

brucek


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## terry j (Jul 31, 2006)

Bruce, sorry, didn't mean to muck you around. Tried to ensure all the relevant data was included, however it meant going to another post, and in the end I didn't achieve what I set out to achieve! The soundcard is the same as Vaughans, a CMedia 8738. (I'm assuming its exactly the same, as c-media wave device comes up in mine exactly as it does in Vaughans post).

I'm pretty bloody slow when it comes to computers, so the thought of posting a picture gave me the willies! However, it is exactly the same as the picture posted on Vaughans post, with the changes being as noted. I will post this reply hoping that it speeds things up ( please find Vaughans post )http://www.hometheatershack.com/forums/bfd-rew-forum/1151-cant-get-work-2.html#post8644

I remembered tha there was a link button at the end of each post, I tried putting that in here, hope that is what all the writing is that suddenly appeared above!

Today, I will hunt around and find out how to post a screenshot, just wanted to send the reply off quickly.

Thanks a lot

terry


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## brucek (Apr 11, 2006)

> Today, I will hunt around and find out how to post a screenshot


Here's a step by step of how to post an image here at the Shack.

I read through the post you referenced and wonder if you have tried everything mentioned in that post. Specifically the cabling and stereo adapters of the loopback required for calibrating the soundcard and also the mixer settings.

brucek


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## terry j (Jul 31, 2006)

bruce, pretty **** certain that everything is done and hooked up correctly as per the help files. As soon as I get to calibrate soundcard I get the results as on the posted link. Haven't had time yet to read the info on posting pics yet, we must be operating on different times at the mopment, can't get to serious reading for at least an hour or two. Can pop on quickly every now and then tho.

Also aked Vaughan if he solved the prob, hopefully he will log on and let us all in on how he fixed it!

the rsults change when I use 44.1 khz, the -3db points (on paper) seem ok at 2.7 hz and 19.9765 Khz ( up from 2.6 hz and 5.554 khz) but the actual plot looks **** still. Will post this answer quickly, and if you need to see the graphs still hopefully I'll have the info in that link sussed out by then.


lots of love

terry


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## terry j (Jul 31, 2006)

this is a test upload of the graph at 44.1 khz









wow, that worked. thanks Bruce.

the graph for 48.1 looks identical, the only changes seem to be the -3 db point.

anyway, will send this off. Gotta keep reading to see how to get the whole page in, not just the graph.


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## brucek (Apr 11, 2006)

To post a screen shot you first save a copy of your computer screen by pressing the key on your keyboard called 'PrtScr' (print screen). 
Then open the Windows 'Paint' program (in Start/Accessories) and then 'Edit/ 'Paste' the screen shot to it. Then save as a jpg and post the jpg.

Perhaps post a picture of the settings that John mentioned in the other post.


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## terry j (Jul 31, 2006)

hi guys, trying AGAIN!

Getting the data saved into paint no worries, but when I upload it takes for ever. Are they under the same size constraints as the other graphs?, and if so how do I set the image limit sizes.(assuming that could be the problem.)

Whilst I'm sorting this out, John, just to clarify, were you asking for the windows mixer panel?

Hope you guys are still on, we may have hit a common time window!


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## terry j (Jul 31, 2006)

had a little look at things, the screen shot I saved has a size of over 1 meg, see from the attachment stuff that a jpg has a limit much less, so that is probably the problem. How do I edit the image to come in under the limit?


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## terry j (Jul 31, 2006)

looks like I missed you guys for another night, oh well.

So I hope this post helps us home in on any probs we need to sort out.

For the life of me could not get my print screen to upload. As I say, think that is because the sheer size of the file is too large? If so, how do I 'tame' them?

Looking further in the help files than I've managed to progress, I see that very soon we end up using receivers for home theatre, of course my only interest is in 2 ch. So, are there any posts I need to be au fait with regarding using good old uncomplicated stereo and REW?

At the moment am using a 3 way set up, am seriously looking at integrating a sub with that. Even if I don't get around to that, bringing the bass totally under control is appealing. Spose I should mention my system is tri amped using the Behringer DCX 2496, so even if I don't end up using an additional sub then bringing the bass under control is a worthy goal.

Eventually will be replacing the Behringer with the DEQX, which can handle at three way, so hopefully using another of the Behringer products I can integrate a sub.

So for now, having the REW as room analysis , in conjunction with room treatment is where I'm heading. Catch you all another day, thanks for you interest so far


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## brucek (Apr 11, 2006)

> As I say, think that is because the sheer size of the file is too large? If so, how do I 'tame' them?


When you did a 'SaveAs' in 'Paint' you likely saved as a .BMP file which is quite large. You must save as a .JPG or better still is a .GIF file. The selection for type of file is in a pull down box in Paint directly below where you enter the saveas name. Maybe try that agiain. The GIF type will be very small and loadable onto the forum.



> my only interest is in 2 ch. So, are there any posts I need to be au fait with regarding using good old uncomplicated stereo and REW?


When it comes to REW we only normally deal with the sub and the mains. So, two channel is what we use when setting up a sub - not multichannel. Generally the sub is set up with its filters first and then the mains are added to check for interaction around the crossover area that might require tweaking of the filters.



> John, just to clarify, were you asking for the windows mixer panel?


I would say both the Windows mixer and the soundcards own mixer/parameters setup screen.

brucek


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## terry j (Jul 31, 2006)

Hi Bruce,
No, definitely saved as .jpg, in fact I'm now quite proud that I actually thought to check that point! Although, am now wondering if I needed to use capitals? Will of course find out soon.

No, my only confusion re 2 ch was the fact that I'm only using stereo amp, obviously has no sub out. It will remain that way until the time I get an amp, then the Behringer. However, will be able to use the low frequency analysis data to confirm and tweak the inbuilt room correction function on the DEQX unit. Indeed, possibly will simply be able to load suggested filters from REW into the DEQX, as it uses standard parametric 'terms' like F, Q and boost. However, cross those bridges as they come, certainly seems doable from your response.

I've hunted and searched for a specific soundcard screen but can't find any such animal. Have seen it once, but it kinda dissappeared and now don't know where to find it.

Anyway, looks like it uploaded this time, and as .jpg too, so absolutely no idea what happened earlier.

















hope this is useful, if there is a specific soundcard thingy you need I'm afraid you may have to steer me where to find it. (It's bad enough having to walk people thru the process on REW, without doing a crash course on computers as well!)

lots of love

terry


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## brucek (Apr 11, 2006)

OK, a couple of points.

I'll be sure John looks at this too.

You have shown the *Playback Mixer* - seems correct. To access the *Recording Mixer*, pull down the Options selection on that playback mixer panel you show and select Recording. Then be sure the Line-In is selected on that recording panel. Note on the playback panel the check boxes are Mute, where on the Recording Mixer they are Select.

The soundcard specific setup/mixer controls are always started up in START / *CONTROL PANEL*. They may give it a goofy name, but it should be there. For example my RealTek AC97 Soundcard selection in the Control Panel is called Sound Effect Manager - duh.



> Indeed, possibly will simply be able to load suggested filters from REW into the DEQX, as it uses standard parametric 'terms' like F, Q and boost.


Oh for sure. When you run REW, just pull down the Equalizer selection and it allows you to select several types of EQ units. If you select the Generic unit, the filter suggestions are then calculated in "Q" instead of "BW".....

brucek


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## JohnM (Apr 11, 2006)

You might also find the controls for your soundcard in a Programs group somewhere, maybe under "C-Media". Note that when you just want to capture a single window rather than the whole screen hold down the Alt key when pressing Print Screen, that way you just capture the currently active window.


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## terry j (Jul 31, 2006)

thanks boys, 

Thinking about why I couldn't get my shots to upload before, reckon it's because I saved the file in save as, then typed in.jpg manually, ie didn't know I was supposed to select from the dropdown bit in the window below. That type of stuff is prob second nature to you guys but to dummies like me ..makes it very real how hard it is (for example) to write help files which are comprehensive enough yet not inordinately long - the question I suppose is 'where do you draw the line?'. Anyway, getting there with your patient help.

Never had to use the recording tab on the mixer before, didn't even know it existed. Hope the problem jumps straight out at you.

Found the other thing I mentioned I'd seen before, hope it's what you want. Fpound it in programs under PCI, and all this time I thought I was using a c-mdia device...duuhh









Just watching what happens in the upload phase, my data actually gets sent to the shack eh? Then I guess it gets read back at your end or something.

Anyway, if that audio rack thing was what you were after then let me know what part of it you need data from.

Bit counter intuitive in the mixer, mute on one and select on the other eh.

lots of love

terry. 

I should have stayed up later this morning, had no idea you guys would have answered so quickly!


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## terry j (Jul 31, 2006)

whilst you're all having a kip (assume it's night where you are) thought I'd try as much as I could re the new settings. Not much at all changed. All effects are off, 2 speakers selected, don't know what else/variation to try. The (seemingly) best results are taken at 44.1 Khz









As you can see, the graph is still rubbish ( but better), but at least the -3db points look better.

The actual rms output at 1khz is way down, have seen that better.









Ah ha looks good now, but unfortunately it's a cheat, as the smoothing has been applied.

Hope you guys have a brainwave, but it is starting to feel like I'll need a ( new) new soundcard.

lots of love

terry


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## JohnM (Apr 11, 2006)

Windows Mixer settings look fine, so the problem is likely to be in the Audio Rack settings somewhere, some kind of effect still turned on or perhaps a loopback feature enabled. It might just be that the soundcard's clock stability is very poor, but more likely to be a setting somewhere. Even as is it may be OK for low frequency measurements, but would be best to get the settings sorted. What's in the Audio Rack settings menu (button bottom left)? A last ditch option would be to try uninstalling the Audio Rack software, but there would be a risk of the soundcard not working afterwards.


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## terry j (Jul 31, 2006)

john, 
bottom button left is wher I did my checks posted earlier.It's a hammer and spanner symbol. ie the advanced section.

Takes me into speakers, set them to 2. (also tried headphones today, no diff)

then next tab is volume, all sliders up

next tab is sound effects, all off

next tab options, all off, only relates to what you see I guess, meaning hot keys etc.

Thats it for that button.

Send this off quickly, hope to still catch you. For what it's worth will have an outboard soundcard to try in 24 hrs, but of course the optimum soln is to get this running.

Maybe it will be a case of an incompatible soundcard. Has that ever happened before?

kind regards

terry


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## JohnM (Apr 11, 2006)

There are soundcards which don't work well with measurement software. In some cases it is due to the cards using different clocks and sometimes different clock rates for the replay and record sides, in others there are hardware monitoring features which cannot be bypassed. And some cards are just ****  Worth looking through the various other menus you can find and the help text to see if there are any references to a monitor or loopback setting, failing that I would try uninstalling Audio Rack before going out and getting another card.


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## terry j (Jul 31, 2006)

a bit worried about uninstalling , it comes up (when click on uninstall audio rack) do I want to u8nionstall it and all it's systems. It's the all it's systems that worries me, as you say, maybe soundcard won't work. That may be ok in itself, as I could re-install it, but I don't think I've got the disc! Aargh


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## terry j (Jul 31, 2006)

tell a lie, found the disc - what's you're advice oh wise one?


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## JohnM (Apr 11, 2006)

If it was me, I'd do the uninstall, reckless fiend that I am :bigsmile:


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## terry j (Jul 31, 2006)

thanks a lot! Just a one too many beers tonight, and tomorrow the 'test' soundcard turns up so what the ****, sometime tomorrow will uninstall, see what happens, try the new one, see what happens, have a few more beers, know what happens, then report back to home base and let all my fellow buddies know whats going on.

Thanks for all your help ( both of you) and fingers crossed for some meaningful results by this time tomorrow

lots of love

terry


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## terry j (Jul 31, 2006)

just found out that I won't be getting the different s/card tonite ggrrggh so just a quick update. Managed to uninstall the audio rack, the music kept playing and so thought I was home and hosed, but alas absolutely no change to the results.

Will have to go on a round trip now to get the bloody thing, so will update as soon as I can. If any brainwaves happen in the meantime don't forget to give a holler! Looks like I have one of those soundcards you described earlier, as you so eloquently described them, ****.

lots of love

terry


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## brucek (Apr 11, 2006)

> Looks like I have one of those soundcards you described earlier, as you so eloquently described them, ****


Yeah, and I'm surprised. I thought anything could be forced into submission..

It does look like you could use the card for lower frequency work, by saving the soundcard.cal and editing it (it's just a simple txt file) for frequencies up to a few thousand hertz. (which would satisfy most people). Certainly from 0hz to 2Khz it looks just fine....

Have you considered this? Realize the Radio Shack Meter only is accurate and usable up to about 5Khz anyway..... Most people use REW and their soundcard for 10Hz to 200Hz duties. It looks like yours would be fine for that if you saved and edited your soundcard.cal file

brucek


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## terry j (Jul 31, 2006)

thanks bruce, in actual fact using it up to 2k is more than adequate right now, I do hav a beh. mic, running into a DEQ 2496, so I'm hoping one day to be able to route that signal into the soundcard.

iS THERE A POST YOU COULD POINT ME TO (god I hate that, sorry, ) where it covers the points on what you've suggested. That would save me a three hour round trip to pick up the other soundcard now, get it next friday instead. Hoipe you're online still, gotta make a decision soon about whether to head off or not

lol
terry


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## brucek (Apr 11, 2006)

When you save the soundcard.cal file (as explained in the REW HELP FILES) under Calibrating the soundcard, it will create a text file of the corrections for your card. I suspect the values up to about 2Khz are OK. I simply meant to edit it with Windows Notepad to remove the garbage above 2KHz or from where the garbage starts..

Attached is a small portion of my soundcard file. Look at it and see what I mean by it being text. Right button and Save target into your computer and then open it with Notepad. You'll see the correction values from 10Hz to about 1000Hz. The real file goes from 10Hz to 20KHz. If I had garbage from above 2Khz, I could simply remove the values above 2Khz if I wanted. This would make a usable cal file for you to use for low frequency work - your card only goes nuts above ~2KHz.

Make sense?

View attachment SoundCardCal.cal


brucek


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## terry j (Jul 31, 2006)

yeah will try, thanks for answering quickly, didn't catch it straight away as I was mucking about with the google me feature. WOW, what a marvellous bit of program, zeroed in right to my property, could see the boundary lines and all, could even place the marker quite accurately within the property, amazing!!!

thanks, will get onto it now, then I will be able to answer your question whether it makes sense!

lots of love

terry

of course it didn't work, clicked on my google me and came up with a blank page. anyway will sort that another time


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## terry j (Jul 31, 2006)

updates

first, thanks to 'the younger generation' got the google me going, still mightily impressed with it!

Also, am mightily impressed with REW, esp as it has been freely given to us all ( hope you're feeling validated John ((hope I got the right guy!)).

Thanks bruce, I've got some sort of soundcard cal filed away. Carried on after that, was very, very, very dissappointed to be still getting garbage results, totally unreadable results.

Pressed a few buttons (basically pounded the keyboard blindly in total frustration) and now it seems to be giving useable and useful results!!!









don't worry about any of it making sense, just pressing this button and that, reading help files etc.

thank you all so very much, will still get the other soundcard but that can wait.

Looks like it will be a breeze to get something happening next time someone logs on with the same graph eh!

will keep playing, reading the help files on the forum, will share my successes with you too

have a good one

terry


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## brucek (Apr 11, 2006)

OK, a few points.

I hope you have loaded the meter calibration file that matches the Radio Shack Meter you are using found here (i.e. newrsanalog.cal). One of the three meter cal files has to be loaded into your computer. Simply store the file in the REW directory and pull down Meter in the REW program and load the meter cal file and select where you stored it.

It doesn't look like you loaded any Soundcardcal.cal file given the ruler flat response showing for that. Were you not able to create and edit that file? Could you post/attach the first 1000Hz of the file for me to see.

You have the CENTER Tab selected to test in REW. Was that your intent? If you want to test your subwoofer (I presume you do), then select the SUB tab in REW.

Once REW is hooked up and ready to go, there is an order that should be followed to get REW setup properly.
Roughly it's this:

Hook up cables - start REW - ensure meter cal and soundcard cal loaded. - select SUB tab - set cutoff frequency (i.e. 80hz)

1. Set Measurement Level.
2. Set Input Volume.
3.Calibrate SPL reading.
4. (if not previously done with a soundcardcal file in place) Calibrate the Soundcard here.
5. Set Target Level
6. Automatic Measurement.
7. Find Peaks
8. Assign Filters
9. Optimize Gain & Q.

Does this help?

brucek


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## terry j (Jul 31, 2006)

thanks bruce

you were right, well spotted. Now loaded the correction file, can see how the line changed.

I just successfully ( I think ) edited the soundcard file, deleted everything above 2000 hz. which I must confess I hadn't done at the time of last post. Maybe it wasn't a successful operation after all, I just tried attaching it for you but got an invalid file error message. I see yours was a cal file, mine only seemed to be a text file(?)

Centre was selected simply because what I'm listening to that is connected to the computer right now are bookshelves, only really go down to about 50 hz. Will use these till I get the hang of the program.

your little summary does help, on the first few? readings of the help files that intrinsic simplicity of the procedure gets lost under the verbiage of the explanation.

right now, the only unclear point in your summary for me is the set target step, didn't quite get it last time. Won't worry too much yet, will go thru it again with the correct files loaded etc. 

Have not got any processor yet, nor even a home theatre amp, just using two stereo amps in a bi-amp config on the speakers. Will do a bit more reading on the forum re the pros and cons of the different choices. Yes you're right, basically want to tame the bass, so will at the very least have to wait to lug everything into the other room in order to be able to hook it up to my full range.

Just thought of something that you may be able to answer, and depending on that answer help decide which unit to go for. I will probably use my existing 3 ways and put a sub into the system. The three ways are currently tri-amped using the beh. dcx2496, but will sometime reasonably soon upgrade to using the deqx unit to tri amp. My problem is how to get a sub into the system, mainly the hookup. Can any of the units usually considered plug into such a system easily? As my limited understanding of the matter stands, they would normally plug into some sort of low frequency output from a receiver, that is all the xover and processing is done. In a purely stereo sit ( no amps with lfe out or whatever) is it getting complicated? I don't expect you to solve this problem for me, but your knowledge of the products may give an exact answer. Hope that all made some sort of sense!

Will reply now, but may leave the question on my invalid file, and whether that means I have successfully edited my soundcard file, till tomorrow as its early in the morning. By the time I get back to it you amy be able to assure me I've got a functioning file, or how to save it correctly.( just had another quick look, the file extension is cal so not really sure why I couldn't upload it to you). I got rid of thousands of values in notepad, but when I load the cal file in soundcard it tells me I've loaded 22050!, so obviously not completely successful yet.

Will sleep on it, maybe I can think a bit more clearly later

lots of love
terry


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## terry j (Jul 31, 2006)

had another quick look, think where I'm getting stuck is after notepad. I get rid of all the data above 2000, and it gets saved in a folder I made. When IO look it up again I can see a txt extension on it. When in notepad and use the save as function, there is no optio I can select that gives me a cal extension./

So, I've got the file edited to only use the data below 2000, but I guess it's just sitting there unusable at the moment.


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## terry j (Jul 31, 2006)

hey!!just did it I think, loaded a s/card calibration file (even had a txt extension) and the dialog box told me I only loaded 2000 points!!


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## brucek (Apr 11, 2006)

> I see yours was a cal file, mine only seemed to be a text file(?)


The extension doesn't matter really. I just used .cal to remind myself and to be consistent with the help files. A .txt is easier I suppose since you can simply double click and Notepad will be the editer. With a .cal extension you have to double click, then select Notepad as the editor. Either way, look at my attached soundcard file above and see what it looks like up to 1000Hz. Yours will be the same except a bit longer up to 2000Hz. You should be able to attach it unless it's larger than the site allows, but it tells you if it's too big, so there should be no problem attaching it.



> the only unclear point in your summary for me is the set target step, didn't quite get it last time


The target is basically used to determine the filters that are created when you push Find Peaks / Assign filters. It tells REW where the response is above or below the target line. You can manually set it also.



> In a purely stereo sit ( no amps with lfe out or whatever) is it getting complicated?


No, it's fairly easy to do what you want. I don't have enough information on your sub or your source (pre-amp) that you feed the power amps with, so it's hard to be specific.
But, generally at the source stereo *output* (which is a low impedance, line level signal) you would split the signal with a "Y-splitter". There will be no loss, since the devices that the outputs of the Y-splitters will feed are high input impedance.

One free side of the splitters (Left) and (Right) channel will feed a BFD DSP1124's left and right channel. The left and right channel output of the BFD then feed a sub with left and right input. The sub will be used to control bass management, since it is being fed a full range signal. Since I suspect your mains are also full-range, then it would be wise to choose a low crossover at the sub around 40Hz to 60Hz to simply compliment the lower end where the mains naturally roll off.

Here's the rub. If the sub doesn't enjoy a left and right channel input and only has a single LFE input, then you will be required to add a combiner to create a mono channel of the stereo signal to feed the sub, like this. It would connect at the output of the BFD before the sub. I haven't tried this specific device, but it looks OK.... 

Make sense?

brucek


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## terry j (Jul 31, 2006)

yes, just found it under the view option, in calibration files details, meter/mic is the newrsanalog.cal,,,,soundcard calibration file is a file with a txt extension, the one I made earlier

so, progress made thankyou, sleep well !!


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## terry j (Jul 31, 2006)

sorry posted without knowing you'd already replied! will digest it tomorrow, pretty knackered now, thanks heaps


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## terry j (Jul 31, 2006)

righto. First the good news. Load the program and I'm informed that the calibration file for the mic is loaded, then informed that the figures up to 2000 hz have been loaded.


then as per the standard steps set

1. Set Measurement Level.
2. Set Input Volume.
3.Calibrate SPL reading.
4. (if not previously done with a soundcardcal file in place) Calibrate the Soundcard here.

As they have been loaded we are fine up to here. First question. The help files all talk about using the AV processor, and selecting which channel to measure. ( By the way, what is TMREQ ?). I have my out put connected to the input on the preamp, can hear the sweep tones etc etc, but it is always in both channels. Do I manually disconnect each channel in turn to make the measurements?, ie are they not controlled from the software?

Ok, taking each channel in turn, by connecting and disconnecting as required, and with a seperately set target level for each (?) I can take automatic measurements.

For the sake of the exercise, I'm using my bookshelves as 'mains' ie the left and right, and selecting bass limited at 50 hz. The readings only go up to 200 hz.

However, something is obviously very wrong. The preamp is the deqx unit, and just by way of explanation has eq filters. As different filters are selected obviously the sound changes, and so should the measured response. Don't worry about the actual eq settings, they are just at random but opposite ends of the spectrum


































As you can see major changes in the eq settings (can hear the difference with pink noise for example) but hardly any qualitative changes in the 'measured' response. Is at a lower level, but that would be expected from the relative eq settings. Funny thing is, if the levels are diferent then the mic is picking up something different, yet the graphs as such don't change.

Anyway, let's start another round!!


lots of love

terry


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## JohnM (Apr 11, 2006)

Look at the numbers on the left of the REW graphs, there has been a huge change in the results. Bear in mind that in the REW plot you are loking at a narrow range, 20 to 200Hz, whilst your DEQX filter is very broad, spanning about 20 to 800Hz, so the main effect of that broad filter on the narrow REW measurement is to shift the overall level within the measured range. Try measuring the effect with a much narrower filter and/or measure over a wider range with REW and you'll start to see more correspondence between the plots. 

TMREQ = Tag McLaren Room EQualisation, an EQ feature that was part of the TAG McLaren Audio AV32R and AV192R AV processors.


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## terry j (Jul 31, 2006)

thanks John, just thought you'd like to see this, as a direct result of your observations. Kept exactly the same settings on the deqx as before

















as you can see, there was a bit of difference in the end!

will keep mucking about now, thanks for that. Will manually pull out each channel for measuring, thanks.

realised I've got the wrong limits on the vertical graph, but what is important is that you spotted the problem

lots of love

terry


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## brucek (Apr 11, 2006)

> Do I manually disconnect each channel in turn to make the measurements?,


You can either just reconnect the REW signal to the channel of interest, or disconnect the speaker of the other channel(s).



> ie are they not controlled from the software?


Hehehe, and since REW mono signal is output on a single analog channel from your computer, how do you propose it control your different receiver channels? :huh: 



> Ok, taking each channel in turn, by connecting and disconnecting as required, and with a seperately set target level for each (?)


The target would likely be about the same for both mains.



> realised I've got the wrong limits on the vertical graph, but what is important is that you spotted the problem


Yeah, this is something you have to watch for. REW will change the vertical scale to accomodate each measurement. To keep consistancy you have to return to a standard scale each time (we use 45dB to 105dB usually). You can enter the scale limits for easy retrieval into the Set Graph Axis Extends button on the bottom right of the REW graph. Then when you click it you can easily press one button to set your favourite axis limits after each measurement if something has changed.

Your speakers are dropping off fairly rapidly below 60Hz.

brucek


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## terry j (Jul 31, 2006)

hi bruce,
just found the diagram you provided in one of Sonnies sticky posts, shows the right out splitting into two for the l&r aux in.

"""Hehehe, and since REW mono signal is output on a single analog channel from your computer, how do you propose it control your different receiver channels? """"

What, by now you haven't realized I'm a computer illiterate!?!

Yeah, the speakers have got a 60 db/oct high pass filter on them at 50 hz. You got that one right.

Will keep fiddling for a little while longer, but I guess I should put it to use with one of the units. Gotta get a sub too! Will hunt around the posts and see which model is the best to get.

look after yourself, have a breather while you can cause I'm sure I'll be back ha ha ha ha, with more dumb questions, (evil) ha ha ha ha!

thanks guys

terry


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## terry j (Jul 31, 2006)

hi everybody

finally borrowed my mates external soundcard, creative soundblaster. The results are a lot better, tho nowhere as flat as the external souncard example in the help files, only as good as the internal example in the help files ( boy that sentence sounded awkward!, hope you understood).

I have been mucking about equalizing the bass, but not using the bfd, but will start a new thread because it may be of interest to others ( yeeeah, will finally be able to help and contribute!), and will make a few points that I've learnt on my way.

I won't bother posting pics of the soundcard response, but I am up and running and very happy indeed so will end this thread with a final thankyou to you all.

lots of love

terry 

:whew: :bigsmile: :jump: :kiss:


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