On the spectrum analyzer there are a few features which will be helpful to understand if you're going to use the analyzer for tuning purposes. The RTA offers three types of memories and works in either the 'real time' mode or 'memory' mode. You can choose to work in either mode but to begin with, you can try the 'real time' mode (the first black switch in the left column, apologies for the unclear pictures).


You can also choose what you want to monitor- the peak signal or the average signal (the second black switch in the left column). And there's also a RESP switch or response selector (second switch in the right column), in other words the speed of display of the response is selectable from '"1" fast, "2" medium, "3" slow. Finally, set the reference level (the blue pot to the right side of the pic) to around 90 or 100 dB depending on how loud your event is going to get(rough assumption). In the case of the recital hall, a reference of 100+ is always used.

After having set the analyzer, bring up the pink noise fader and observe the response of the left speaker stack on the RTA, you will see a graph displaying the various frequencies that are either 'peaking' or 'low', that is your cue to go ahead and now alter the frequency response of the left speaker stack with the help of the 31-band graphic equalizer.

The objective is to attain an optimum flat response but don't try to achieve a complete flat response because the way the room sounds without the audience would sound different once the venue gets filled up, therefore attain a response which is 'partially flat' but not completely flat.

The same method is repeated for the right stack and then finally place the microphone to analyze the response of the venue from a 'central' location (as shown below).

Along with this always use a CD, which you have been listening to for quite some time and you know exactly how the music sounds or should sound since you've been listening to it on your own stereo system; a mastered CD is always a preferred choice.

As you equalize the respective channels, also compare the equalized sound to the non-equalized sound by playing the CD and listening for the difference; at first the result might sound drastic or a bit 'weird', perhaps because of boosting or cutting a few frequencies but eventually your ears would get accustomed to the 'new' or equalized sound, because when you observed the non-equalized frequency response, the loudspeaker was capturing the sound coming off the surfaces or pillars in the recital hall and the frequency response showed you that, but by equalizing the system you made changes to those problematic frequencies.

Also bear in mind, that once the hall gets filled up you might have to tweak a few frequencies here and there to get a fine balance.

Good luck!

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