Phonic PCR2213, User Manual

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3. Turn the threshold all the way up, and switch on limiters.
4. Let’s start from the HF output.
5. Turn up the mixer master level until the HF power channel reached the threshold power you want to limit.
6. Turn down the threshold until the HF limiter indicator lighted. Now you have done the first limiter point.
There are 3 more (or 2 more ) to go.
7. If you keep all the output levels on PCR2213 at 0 (12 o’clock), the LF output of the same channel prob-
ably reached limitng at the same time. But the power amplifier level maybe higher or lower than the power
you wish to limit. If the limiting point is not yet reached, increase the mixer output level until the limiter
indicator is lighted. If it was too high already, bring down the mixer output level until the limiter indicator
just start to light.
8. Mark the output level at this point by measuring with AC voltmeter.
9. Turn up the level control of the power amplifier channel until it reached the level you wish to limit.
10. Turn down the output level of PCR2213 until the power amplifier output level reduced back to the level
marked in step 8. Now, this output limiter is done.
11. Repeat the same procedure for other output limiter.
12. After all limiter points are set, connect all the speaker loads back and send in the pink noise via the mixer
again at –20dB (or –30dB) refer to previous level.
13. Measure the HF amplifier channel used for previous setup and write down the value.
14. Measure the other HF amplifier channels and adjust them as the same as the write down value.
15. Measure the LF amplifier channel used for previous setup and write down the value.
16. Measure the other LF amplifier channels and adjust them as the same as the write down value.
5.6 SUB
In case the PCR2213 is used to work with sub-woofer system, no matter mono or stereo, it is good idea to drive
all the sub-woofer boxes in the same phase with identical signal. Keep those sub-woofers the identical design
with identical boxes and drivers at all possible.
Slide the sub sigma switch will sum the 2 LF output of PCR2213 in stereo mode and send out the signal from
both LF output jacks. This function will be automatically dis-engaged when the mode is set in MONO instead of
STEREO.
This practice is true no matter it is a big stage installation or small in studio monitoring.
5.7 HORN EQ
30 years ago, the horn designs could not reach constant dispersion over the frequency range it covers. The
higher the frequency, the narrower the covering area.
20 years ago, the design of constant directivity can be realized, so that the energy can be distributed wider
area especially in higher frequency. This expose a problem not noticeable in the past, because the high
frequency energy output from the driver will drop gradually as the frequency goes higher. It was not a problem
on axis before these constant directivity horns invented, and compensated with the beaming characteristic of
older horn.
But to take good care of the audience in various venues, constant directivity design provides much better
performance between on axis versus off axis.
To compensate this roll-off tendency, PCR2213 provides a HORN EQ switch which will boost +12dB at 15KHz
with a 6dB/oct slope. This is a generic curve and work fine with most constant directivity horns, however fine
tune may be needed with 1/3 octave equalizer.