Input Level - Classe Audio SSP-25 Owner's Manual

The configuration of "input" allows you to play a trick or two on your system. If you
set the "input" to "auto" and direct both digital and analog signals it, it will play the
digital signal, but if the source for the digital signal is removed (turned off), the
program material on the analog input will immediately begin to play. If you have
finished watching a movie on a DVD or laser player and you turn off the player
any analog signal being sent to the same input will automatically begin to play at
once.
Also see the note regarding the AV4 input below.
Though the factory default has been set to "auto", in most cases you will want to set the "Input" to the kind of source
plugged into the input: if it's an analog source, set the "Input" to "analog", and if it is a digital input set it to "digital."
To change the "Input" press the "/\" key or the "\/" key. Either key will work, but the "/\" key will cause the choices to
cycle from "auto" to "analog" to "digital" and back to "auto." When your choice is displayed press the ">" key to set your
choice into memory and move to the next option: "Level:."
5.4.5

INPUT LEVEL

All digital sources conform to standards that make "input overloading" virtually
impossible. However, analog signal strengths (output voltages from different
source components) often vary widely. You've probably noticed this as an abrupt
and annoying change in relative volume when you switch between tuner, tape,
and CD on a conventional preamplifier. Under extreme conditions, a very strong
input signal can "clip" the input circuitry and cause potentially damaging distortion.
The SSP-25 solves this problem with sophisticated Input Level adjustments for
each analog input. In addition to eliminating level shifts when choosing a
different analog source, the Input Level calibration help insure optimum,
distortion-free reproduction of even the most dynamic sources.
Begin to set analog input levels by making sure that you've connected each
analog source component to the appropriate input on the SSP-25. Turn on each
component.
For CD players, obtain a test disc with a "full scale" white noise test track. After
selecting this track, press "play" and, if your CD player allows, select "repeat
track" to provide a constant test signal.
Set your audio tuner to FM and select interstation noise, usually by defeating the
tuner's "mute" circuit and tuning to an unused frequency between two broadcasts.
For cassette decks, first record either the CD's white noise test track or the
tuner's interstation noise at a 0 VU level. (Yes, you will lose some high frequency
content this way but don't worry about it -- the object here isn't high fidelity, the
point is to create a relatively constant signal source.) Then use the tape in the
same way you will use the test CD or your tuner's white noise. Obviously, the
longer you record, the longer uninterrupted playback time you'll have. This will be
useful while setting Input Levels.
Some Notes on Input Level
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