Help Set Up Signal Path Please

[pinoybboy2004]

Hello everyone.

I need some serious help ringing out a room we're using for live music every night!

Here's the situation;

The sound card on my laptop does not have sufficient output (only mic ) we have a PC in the sound desk.
Have a M-Audio Fast Track USB
Have a DBX RTA mic
Have a DBX 31 band EQ
Have required cables
Using a Behringer SX3242 (if required)

I'm not sure what to do with my laptop and the M-Audio Fast Track. Does the USB cable transfer the audio signal or recieve it? If I need to use the PC I can just move the program files to that and run if from there.

Any diagrams or signal paths that you can illustrate what needs to happen would be much appreciated.

The goal for me to complete by the end of REW is to obtain the data indicating what to boost and cut on the 31 band EQ.

[Wayne A. Pflughaupt]

Welcome to the Forum Brent!

Have a DBX RTA mic

You’ll need a calibration file for it. You’ll also need an SPL meter.

I'm not sure what to do with my laptop and the M-Audio Fast Track. Does the USB cable transfer the audio signal or recieve it?

The USB interfaces between the measurement mic and the computer. For connections to the sound system, use analog.

Any diagrams or signal paths that you can illustrate what needs to happen would be much appreciated.

http://www.hometheatershack.com/forums/spl-meters-mics-calibration-sound-cards/10001-rew-cabling-connection-basics.html

The goal for me to complete by the end of REW is to obtain the data indicating what to boost and cut on the 31 band EQ.

Are you able to do that by looking at the response graph REW will generate?

Smoothing response isn’t necessarily a safeguard against feedback (which I suppose you meant by “ringing out the room?”). A quick and easy way to do that is to set the mic(s) on stage and raise the volume of the system until the feedback starts. Then ride up and down the gain to keep the feedback under control and see if you can find the slider on the equalizer that will take out the feedback, and cut it a few dB. Once that frequency is under control, raise the gain back up again and see if there is another frequency prone to feedback and deal with it the same way. If I have a chance to do this before a show, I seldom have any feedback problems.

Regards,
Wayne

[brucek]

I'm not sure what to do with my laptop and the M-Audio Fast Track. Does the USB cable transfer the audio signal or recieve it?

The USB cable becomes the computer bus (to and from) the external USB soundcard. The M-Audio soundcard will have analog line-in and an analog line-out that you'll use for REW.

The line-out connects to your audio system line level input. The mic you have requires a mic pre-amp to provide 48 volts phantom voltage and to raise the mics low level up to line level, so that the analog line-in port can receive it. Even though your Fast Track has a mic-in, it isn't for that type of microphone. (Unless, of course you have the Fast Trak Pro model, and then it is suitable for plugging the mic directly into it).

Either way, you have a 24 channel mic preamp in the Behringer SX3242, so you will require one channel for the mic. A line output of the Behringer SX3242 will feed the analog line-in of the M-Audio. Only one channel of the M-Audio is used (normally choose the right channel to calibrate and use for measuring - the left channel is unused).

Read and become familiar with the REW HELP files and the REW Cabling and Connections Basics.

Also note the REW information Index and the Download Page.

You require a calibration file for your microphone for REW. There are a few generic ones on this site you can search for and use.

brucek