Appendix B: Setting Sensitivity For Best Gain Staging - Crown I-T5000 HD Operation Manual

I-Tech HD Series Power Amplifiers

9 Appendix B: Setting Sensitivity for Best Gain Staging

Optimized system gain structure maximizes signal to noise within the sys tem.
Adjusting your amplifier to fit within an optimized system gain struc ture is
accomplished by properly setting both the sensitivity and attenuation controls
within the amplifier. I-Tech amplifiers offer 149 sensi tivity and gain settings
allowing very fine adjustment of the amplifier's gain and voltage sensitivity.
The Appendix section of the I-Tech Application guide (online at www.
crownaudio.com) provides charts with sensitivity in volts and gain in dB for
each sensitivity/gain setting.
With other amplifiers, it is often necessary to apply attenuation in order to
achieve the desired sound pressure level. Large amounts of attenuation are not
necessary with I-Tech amplifiers and can, in fact, degrade performance. The
attenuation adjustment should only be used for small (3 dB) or tempo rary
adjustments in amplifier gain. Instead, set the sensitivity/gain of your I-Tech
amplifier so that you can achieve the desired output with the attenu ators at or
near 0 dB.
Example: Suppose that you are using an I-T9000HD with the sensitivity/gain
set at 1.4V/37.1 dB. After optimizing the gain structure of the rest of your
system you find that attenuating the amplifier by 10 dB produces the desired
loudness. The same output level, with improved signal-to-noise ratio and
headroom, can be achieved by using 0 dB of attenuation and by setting the
amplifier sensitivity/gain to 5.81V/27.0 dB (37 dB – 10 dB = 27 dB).
Note: as indicated in the online appendix, the list of possible sensitivity
settings is different for each position of the max input setting. If, while
adjusting sensitivity/gain in your amplifier, you do not find the setting you
need, try changing the status of the max input setting and search again.
Operation Manual
page 53