Rogue Audio Stereo 90 用户手册

 

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After all proper connections have been made, you are now ready to turn the 
Stereo 90 amplifier on. The power on/off switch is on the front of the amp.  Some 
preamplifiers and sources can generate dangerous transients that can damage 
loudspeakers. To avoid letting dangerous transients reach your loudspeakers turn 
your system on in the following order: 
 
1)  Turn on all sources (CD, tuner, etc.) that you will be using.  
2)  Turn on the preamplifier. 
3)  Wait until preamp has stabilized. 
4)  Power up Stereo 90 amplifier 
5)  Select listening source and play music 
 
When powering down your system turn the amplifier off first. 
Note – Important! After turning off the amplifier, wait at least one minute to turn 
it back on.  Do not turn it on then off and then on again in quick succession.  
Doing this will not allow the power supply to discharge between on/off cycling 
and may result in transient noises.  
 
 
Triode/Ultralinear switch: 
This switch is located on the back panel of the amp. See Figure 2. The output 
transformer of a tube amplifier acts as the electrical interface between the very 
different impedances of the loudspeaker and the tube circuitry.  There are three 
fundamental ways that the output transformer can be connected to the tube circuit. 
 
1)  Tetrode or Pentode connection – In this configuration, the highest power level 

is achieved but at the expense of significantly higher distortion levels. 
Practically speaking, this mode of operation is sonically inferior and has been 
disregarded in the Stereo 90 design. 

2)  Triode connection – With this configuration, the lowest level of distortion is 

achieved but at the expense of output power. In the case of the Stereo 90, its 
power level in triode is high enough that it will likely provide plenty of power 
for almost any speaker load. 

3)  Ultralinear operation – With this configuration, power levels near those of 

tetrode mode are achieved with low distortion levels that approach those of 
triode operation.  For loudspeakers that demand very high levels of power, 
ultralinear should provide excellent sound and plenty of power. 

 
The triode/ultralinear switch allows the user to operate the Stereo 90 in either of 
the two modes. In general, the sonic differences are subtle but for a given 
loudspeaker one mode is likely to sound better than the other.   There is a 
complex relationship between the output transformer and the crossover network 
so try both and see which one works best in your system.  This switch can be 
operated while the amplifier is playing but you will hear a small relay noise 
through the loudspeaker.