Measure Soundcard response problem Gadget Labs Wave824

[rhrmusic]

Hi,

I'm having a problem measuring the sound card response. I can perform calibration and measurement level without any problems. The Gadget labs wave/824 is 24bit/48khz with 8 analog ins & outs. There is no mixer device for this... therefore no windows volume or play/record control. There is an control applet that sets mute/monitor and inputs/outputs to +4dbu or -10dbv for each channel. These are 1/4" bal/unbal connections.

I can set the input and output channels in REW but the input and output device pulldown menus are greyed out as in "choose input" and "choose output". I'm using channels 7 & 8 (Left/Right). I use a short 1/4" cable and plug ch8 output into ch8 input and run the soundcard response. It generates the 1k tone and gives back a message that it either didn't detect or the signal was too low for the test, so I cancel the test.

I did plug the output into my pwr amp & speaker and ran the test and heard the 1k tone burst quite well. I also tried all the combinations of input/output at +4 or -10 but always have the same result.

It's probably due to not having a mixing control or default windows mixer.

Any ideas?

Thanx

[JohnM]

Can you set the device to use 16-bit sample depth? If you can do that, REW might see it. Are you able to select it as the default replay and recording audio device in the audio tab of the Windows Sounds and Audio Devices properties?

[rhrmusic]

JohnM wrote:

Can you set the device to use 16-bit sample depth? If you can do that, REW might see it. Are you able to select it as the default replay and recording audio device in the audio tab of the Windows Sounds and Audio Devices properties?

Thx for reply... The sampling depth is 24 bit. It can only be changed in programs like Nuendo and wavelab for those instances but no option for 16bit in the control panel it has. Yes, all the stereo pairs are available/selectable in the windows sound and audio devices tabs for playback and record... and they are set to correspond with REW settings inputs/outputs.

I use two of these in my studio for 16 tracks. I also have an m-audio delta 1010 8/8 that does have a control panel that probably will appear and give options under the REW soundcard menu. I also have a Sound Blaster Audigy LS stereo card that will probably work also. Neither of these are installed however.

I'll probably install the delta 1010... it's a nice sounding system.

Are you saying that REW may not work with 24bit sound cards?

Thankyou

[JohnM]

REW seems to work OK with 24-bit cards, but it actually requests 16-bit interfaces from the audio system. If the devices appear in the Windows audio devices lists they probably have WDM drivers but looks like there is no support for ports, which is why REW doesn't offer any inputs or outputs. In the next version of REW you can just leave the selectors at "Default Device" and it should use whatever the OS offers as the defaults. I guess you tried looping back both ch 7 and ch 8? Or switching the selector in the SPL meter between Left and Right?

[rhrmusic]

JohnM wrote:

REW seems to work OK with 24-bit cards, but it actually requests 16-bit interfaces from the audio system. If the devices appear in the Windows audio devices lists they probably have WDM drivers but looks like there is no support for ports, which is why REW doesn't offer any inputs or outputs. In the next version of REW you can just leave the selectors at "Default Device" and it should use whatever the OS offers as the defaults. I guess you tried looping back both ch 7 and ch 8? Or switching the selector in the SPL meter between Left and Right?

Hi John,

Yes, I tried all above for the wave/824 pci card/breakout box. I went ahead and installed a SB Audigy LS card I had... disabled the gadget labs devices. REW didn't have any problems with measuring sound card response. Although I don't think it came out right. It was late. Today I have a recording session but I'll revisit REW later and see how far I can get.

One question I have... how far away from speaker do I place the mic during calibration? I'll read the forums...

I'm using a Macintosh AA2 Acoustic Analyzer with the CM201 condensor cal mic, not the RS SPL meter. It does the same thing and more... but it functions as an SPL db meter and has voltage output.

Thx for your reply,
Curt

[brucek]

One question I have... how far away from speaker do I place the mic during calibration?

The usual method for Home Theater subwoofer calibration is to place the mic in the listening position where your head would be positioned.

brucek