Sound Card Calibration Help

**eye1** · **04-28-08, 09:48 PM**

I am getting a message that I have a low signal level. Not sure where to look. I appears that I have things hooked up correctly. I am not able to adjust input volume on the settings page because it is greyed out.

Here is what I have so far. The graphs tell me that I am getting a reading from the SPL Meter but is it strong enough?

Any Ideas what this means?

**eye1** · **04-28-08, 09:52 PM**

Here is the sound card calibration graph and the impulse graph. The would not attach to the first post.

**eye1** · **04-28-08, 09:57 PM**

Here are the missing graphs. Too big on the first attempt

**brucek** · **04-28-08, 11:10 PM**

Why is there signal on both the left and right channel. You should have a short cable going from the left channel line-out to left channel line-in. The right channel should be left open.

Adjust the input level with the Windows mixer..

brucek

**JohnM** · **04-29-08, 05:42 AM**

What soundcard are you using?

**eye1** · **04-29-08, 09:52 AM**

Quote:

JohnM wrote:

What soundcard are you using?

I am using the Soundmax Integrated digital audio from my PC
It has a plug in for a mic, output, and what appears to be the input to the far right.

I have followed the set up diagram and i am using the stereo splitters in both the line out and line in.

Does the loopback connection split the signal for calibration?

I have also disconnected everything and only used the right(red) out and connected to the right(red) line in. I still show input to both channels. Hmm.

Could it be the sound card not splitting the channels?

Thanks

**brucek** · **04-29-08, 10:27 AM**

Quote:

Could it be the sound card not splitting the channels?

Or do you perhaps have 'monitor mode' turned on?

brucek

**eye1** · **04-29-08, 10:34 AM**

Quote:

brucek wrote:

Or do you perhaps have 'monitor mode' turned on?

brucek

Where do I check for this? I do not see a monitor mode setting for my integrated sound.

**brucek** · **04-29-08, 11:26 AM**

It would be a feature of the Soundmax Integrated application itself that would be accessed from the Control Panel.

They sometimes have a goofy name for it like "what you hear", or "mixed", etc..............

brucek

**eye1** · **04-29-08, 11:39 AM**

Quote:

brucek wrote:

It would be a feature of the Soundmax Integrated application itself that would be accessed from the Control Panel.

They sometimes have a goofy name for it like "what you hear", or "mixed", etc..............

brucek

Wow, that appears to be the issue. Line in was disabled. Now it is now enabled. I will give it another go.

Thanks

**JohnM** · **04-29-08, 11:58 AM**

Careful - Line In should be disabled for playback, but selected for record. Worth posting screenshots of your playback and record mixer settings.

Also on your main volume control turn the Room EQ Wizard volume up full.

**eye1** · **04-29-08, 03:26 PM**

Thanks for your patience Bruce and John.

I had line in enabled for playback and record line in was enabled. This may be why I was having so much feedback.

Here are shots of my new settings. I will retry again.

**brucek** · **04-29-08, 04:01 PM**

When you select the Speakers in Playback, you want to set them to Default. Then when you select their properties, you want to be sure that the Line-in is disabled. When line-in is enabled in Playback, this is the monitor feature. You want it disabled.

In the Record properties, you want the Line-in enabled of course.............

brucek

**eye1** · **04-29-08, 05:41 PM**

Quote:

brucek wrote:

When you select the Speakers in Playback, you want to set them to Default. Then when you select their properties, you want to be sure that the Line-in is disabled. When line-in is enabled in Playback, this is the monitor feature. You want it disabled.

In the Record properties, you want the Line-in enabled of course.............

brucek

In device usage there is no selection to Default and in properties there is no Line-in to disable.

I do not seem to be able to get there with this on-board sound card.

I can get there with line-in for record.

**JohnM** · **04-29-08, 06:21 PM**

If Line In does not appear in the properties of Speakers that's OK. Re-enable Speakers, in the properties for speakers check that there are no odd controls on the "custom" tab (if there is one), make sure the levels are OK on the levels tab, and select the box to "disable all enhancements" on the Enhancements tab. Also disable enhancements on the properties for Line In and make sure the levels are OK on its levels tab.

Make sure the 3.5mm plug on your stereo splitters looks like the picture in this thread: http://www.hometheatershack.com/foru...on-basics.html
There need to be 3 connections on the plug, there are lots of "stereo" splitters that just have a mono 3.5mm plug that is linked to 2 RCA sockets, they are no good for this purpose.

**eye1** · **04-29-08, 08:42 PM**

Thanks, I think I am making progress now. I referred to another recent thread showing a comparison of a Turtle Beach card to the Vista card. I did find the settings to get it set up with no feed back.

I adjusted all levels on the sound card tab with good results and good graphs. When I get to the Make a measurement step and check levels I get a level is Low message.
The receiver volume is quite high and there is noticeable hum. When I turn up the receiver more I still get the Low Level message. Any Ideas on what I should try?

**brucek** · **04-29-08, 09:08 PM**

Are you checking the Levels with a Subwoofer calibration signal using a subwoofer with the mains turned off?

brucek

**eye1** · **04-29-08, 09:35 PM**

Quote:

brucek wrote:

Are you checking the Levels with a Subwoofer calibration signal using a subwoofer with the mains turned off?

brucek

I dont think so, still using the noise from the main speaker. Its like at this point the SPL is not giving an accurate read to the line in on the sound card. I will see if I can post screen shots soon.

**JohnM** · **04-30-08, 04:30 AM**

Just ignore the levels check on the measurement screen and see what levels you get during the measurement itself.

**eye1** · **04-30-08, 09:28 AM**

Ok, Here are screen shots of my settings and a graph. Can you see anything that is suspect to causing issues? The first step of the measurement screen runs the tone and says the level is good but when I go to measure this is the message that I get.

I will also mention that I have not been able to completely isolate the signal on the graph to one channell during the sound card calibration but the graph seems to look good.

On the playback line levels I have muted all the choices except playback volume control.

Thanks for the help! I have too much time in to give up

**JohnM** · **04-30-08, 12:26 PM**

The level settings on those properties pages all look good, and it is OK to just click "OK" on the warning message about the input level from the measurement. Assuming the final measurement looks OK all you'll need to do is either turn up the volume on your system a bit to get cleaner results or use a lower scale on your SPL meter.

Difficult to understand why there is input on the right channel though, when your SPL meter is only connected to the left, correct? A photo or two of your connections might shed some light on that.

**brucek** · **04-30-08, 01:08 PM**

Quote:

Difficult to understand why there is input on the right channel though, when your SPL meter is only connected to the left, correct? A photo or two of your connections might shed some light on that.

I can only think of two possibilities for that happening.

1. Using a mono connector plug when it should be a stereo plug.
2. Extremely poor crosstalk figure in the soundcard.

Have you, as a test, used the right channel as opposed to the left channel and seen if the results are the same?

Quote:

The first step of the measurement screen runs the tone and says the level is good but when I go to measure this is the message that I get

Keep in mind that the Check Levels routine in the Measurement screen and the Check Levels routine in the Settings screen use different values to generate the pink noise level setup test signal.

The Check Levels routine in the the Settings screen uses the fact that you have the Check/Set levels with Subwoofer pull-down selected to generate its test noise (this a band limited signal with a low and high cut of 30Hz - 80Hz) - but then you are measuring full range up to 20000Hz in the Measurements screen. Even if you were using the Mains Full Range pink noise test signal, it has a low and high cut of 500Hz - 2000Hz.

REW double checks and verifys that the end frequency of the sweep that you have selected in the Measurement panel roughly matches the test signal setting (for sanity), its Check Level routine uses the end frequency as the test pink noise hi-limit cutoff. So if you had 20KHz as the end frequency to measure for your sweep, you can see how the pink noise would be different (between the two Check Levels) and as such the low level signal you're experiencing.

Long story short, use the correct test signal (subwoofer or mains) to set up the levels. If you've done this correctly and the Measurements screen Check Levels sanity test passes, don't worry about a level warning.......

brucek

**eye1** · **04-30-08, 08:13 PM**

You both have given me alot to look at and consider.

Since my settings appear to be correct and graphs look good I will disregard the low signal level by changing the SPL input meter level to get a good signal.

I did attempt to turn the volume up to get the proper reading on the SPL meter but it was much higher than the reference 75dBL range - when the receiver was this loud I would get alot of feed back through the meter - like it was becoming a live mic whith a high pitch.

I will let you know my results hopefully sooner than later.

I do appreciate your help and patience working through this.

**eye1** · **05-03-08, 12:21 PM**

Ok, I am back with results.

Looks like I am having success now. Here are 3 graphs for your much appreciated input on.

The first one for conversation is of simple spl meter measurements.

The second one is to show the sound card calibration.

The third is to show F C R with SW at 80Hz X-Over

The fourth is to show FCR with SW at 50 Hz X-Over

I applied 1/3 Octave smoothing to each. Please not the reading from the SW on each graph. I did disregard the low level warning at the end of the measure because the graphs look to be good - the only thing I would ask is why am I showing at a lower dBL on the graph. The SPL was calibrated and during the measure the SPL does read from about 72 to rise quickly to touch 80dBL at the very end of the measure.

Does it look like I am on the right track with these? What would you recommend I do next?

I thought I would isolate and run a independent measure of each the SW, L and R to help determine the optimal X-Over.

**brucek** · **05-03-08, 01:04 PM**

Quote:

Does it look like I am on the right track with these? What would you recommend I do next?

You're not getting any signal from your SPL meter at all into the PC. The rising levels at either end of the spectrum is from the meter and soundcard cal files.

The soundcard calibration file looks great. That says everything is working fine with your PC. The problem is that you're not getting any input from your microphone at all.

Quote:

I did disregard the low level warning at the end of the measure because the graphs look to be good

In this case the warning is legit. Either your meter or cable or adapter is not correct. Plug the meter into the AUX input of your receiver and sing - it's a microphone - see if it's working..

brucek

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