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

**terry j** · **10-10-06, 03:36 AM**

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

**brucek** · **10-10-06, 09:37 AM**

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

**terry j** · **10-10-06, 07:52 PM**

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/foru....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

**brucek** · **10-10-06, 09:17 PM**

Quote:

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

**terry j** · **10-10-06, 10:21 PM**

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

**terry j** · **10-10-06, 10:39 PM**

this is a test upload of the graph at 44.1 khz

rew graph.jpg

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.

**brucek** · **10-11-06, 03:43 AM**

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.

**terry j** · **10-11-06, 04:15 AM**

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!

**terry j** · **10-11-06, 04:38 AM**

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?

**terry j** · **10-11-06, 06:39 AM**

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

**brucek** · **10-11-06, 08:48 AM**

Quote:

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.

Quote:

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.

Quote:

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

**terry j** · **10-11-06, 01:34 PM**

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.

screenshot..jpg

screen and mixer.jpg

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

**brucek** · **10-11-06, 02:00 PM**

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.

Quote:

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

**JohnM** · **10-11-06, 03:00 PM**

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.

**terry j** · **10-11-06, 07:16 PM**

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

all mixers.jpg

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!

**terry j** · **10-11-06, 09:37 PM**

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

44100.jpg

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.

44.1 cheat.jpg

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

**JohnM** · **10-12-06, 03:16 AM**

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.

**terry j** · **10-12-06, 03:29 AM**

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

**JohnM** · **10-12-06, 03:36 AM**

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.

**terry j** · **10-12-06, 03:44 AM**

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

**terry j** · **10-12-06, 03:45 AM**

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

**JohnM** · **10-12-06, 07:22 AM**

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

Advertisement