Subwoofer Limit - Classe Audio SSP-25 Owner's Manual

The following instructions assume that you have a sound level meter.
Before you begin balancing the output of the speakers in you system you may want to decide on whether to set the
internal white noise generator to "auto" or to "man"(ual). If it is set to auto the SP-25 will automatically cycle white noise
from speaker to speaker. It will pause at any given speaker when you press either the "/\" or "\/" key on the remote
while the speaker is playing noise. When you stop adjusting the level the SSP-25 will return to automatically playing
white noise on the speakers one at time. When set to "man" you can select the next speaker yourself by pressing the
">" key. As you move from speaker to speaker it will play white noise.
To select either method of setup press "MENU", then press the ">" key twice to display "Main menu – System setup."
Select this option by pressing "ENTER", then press the ">" key four times to navigate to "System setup – Feature
setup." Select this option by pressing "ENTER". The display will read "Feature setup – Noise gen.: auto." You can
select from "auto," "off," and "man."
Selecting "off" of course will turn off the noise generator, but it will also make it possible for you to apply your own
signal to a selected input. You will have to move the signal from speaker to speaker utilizing the ">" key.
When you have programmed the feature the way you wish to use it, you can return to "Balanced setup" by pressing
the "MENU" key once, then pressing the "<" (backup) key twice, then pressing the "ENTER" key.
However, if you are accessing the "Balance setup" from full operation mode you must:
Press "MENU", then press the ">" key twice to display "Main menu – System setup." Select this option by pressing
"ENTER", then press the ">" key twice to navigate to "System setup – Balance setup."
Press "ENTER" and see the display read: "Balance setup – Left: +00.0 dB." If you have selected "auto" in "Feature
setup" above you will notice the display change in two seconds to "Center: 00.0 dB" and in two seconds more to
"Right: 00.0 dB" and so on. As the display changes from speaker to speaker each displayed speaker will play white
noise. If you press either the "/\" or the "\/" while a speaker is playing it will continue to play as long as you continue to
adjust its level.
Either sit in the preferred listening seat or set the SPL meter in the seat, (on a stand adjusted to ear level height).
Using you ears if you have to, but hopefully using an SPL meter like the one mentioned in the note above, adjust the
sound pressure level of each speaker to 75 dB. (If you're using your ears the sound should be quite loud, but not so
loud you can't be heard by someone next to you).
Adjustment of sound pressure can be made in 0.5 dB increments. 0.5 dB is too small for you to hear but a meter is
sufficiently sensitive. It really isn't critical that the speakers all have exactly the same output level, but they should be
adjusted to +/- 0.5 dB of each other. This is simple to do with a meter. If you are using your ears, by listening carefully
you should be able to set all the speakers to a satisfactory level.
(If a spectrum analyzer or other narrow-band meter is available, adjust the subwoofer level to 10 dB above the main
speaker levels. A normal "C" weighted meter, like the one noted above, will give you this difference, more or less).
When you are satisfied the speakers are all playing at essentially the same level press the "MENU" key to exit the
programming mode. You can go back to full operational mode by pressing "MENU" two more times, or you may press
the ">" key to move to the subwoofer limiter setup section (see below).
5.5.4

SUBWOOFER LIMIT

We have included a subwoofer limiter in order to protect your Subwoofer from
excessive power that might damage it. The limiter works by preventing the SSP-
25 from outputting more than a certain voltage to the Sub output. You can't
actually hear it work, but when it is set properly the subwoofer will not receive any
more power than it can handle safely.
Some Notes on Subwoofer Limit
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