please share your experiences with a little "how to".

Well, basically, I did this:

- Get the downloadable demo of SpectraLAB.

- Mess with it and learn how to use it.

- Test it with a little cheapo microphone, spectrum-analyzing my voice and the room noise.

- Create some test tones. Specifically, I did a pink noise track as well as a "ten frequency bands" track. The ten frequency bands I created I chose to be the same as the ten frequency centers on the empeg equalizer. I did these in the SpectraLAB noise generator, and used the "save as WAV file" option.

- I also created a twenty-band track which was the ten Empeg bands plus ten more centered between the other ten bands (had to do a little math to find the midpoints between the bands). Then I took the center-bands track and the between-bands track and combined (mixed) them in CoolEdit. This one turns out to be a very useful track, by the way, in determining what the Q setting should be for a given band.

- Locate one of the microphones for which SpectraLAB has a reference file, in my case a Shure SM-58 (I have a friend with an extensive home studio). Loaded up the SM-58 profile in SpectraLAB's "Scaling" dialog box.

- Lug everything out to the garage. Computer equipment is outside the car. Mike cable runs into the car. I discovered that the mike has a very wide dispersion pattern and it mattered very little if it was exactly at my ear position, or just sitting on its little stand on the pocket between the seats. So that's where it's sitting, on a little stand on the pocket between the two front seats.

- Set everything on the player to flat. Loudness, Bass/Treble boost, L/R delay, etc. Turn the volume way down.

- Pick a "blank" equalizer preset and name it RTA 1 or something. Don't mess up your existing presets.

- Play the test tones and mess with your crossovers, amp levels, and EQ settings. Empeg settings can be done with the IR remote control from outside the car with the doors closed (don't damage that mic cable).

Remember while you are doing this, don't blow your speakers by playing the test tracks too loud. These really work your speakers hard, so just be real careful.

Remember that the goal is not to make your car sound perfectly flat. That would sound terrible. The goal is to find unexpected holes (sharp peaks or dips) in the overall frequency spectrum that need correction. For instance, locating a dip where your subwoofer and main speakers cross over would indicate that you need to adjust the crossover points.

After you've located the holes and corrected them, then you can start to work on dealing with the overall sound. I don't know what a "pleasing curve" would look like on the graph, and I get the feeling that this is going to be different for different people's tastes.

I don't have all of this dialed in yet, I haven't done my second pass yet.