16.With no program playing, listen to your speakers. If you hear a loud hum, turn off the ampli- fier, unplug and reconnect the interconnect cables at both ends and turn the amplifier back on. If the hum is still there, try different settings of the two Ground Switches until you find the combination that produces the least hum. You should be able to achieve an extremely low noise floor with the Model 5. However, some sources will pass through more power supply noise than others. If that doesnÕt fix the problem, try replacing the interconnect cables. Some cables have
If none of these steps eliminates the hum, consult your dealer.
17.After about thirty minutes of operation, check the plate current of each output tube again, in Ultralinear mode with no audio signal present.
18.If you want to use the amplifier in Triode mode, turn it off and change the position of the Output Tube Setting switch.
Note: Bias current in triode mode will indicate a lower bias current than
19.If you purchased the optional Full Cage Cover, it snaps onto the top of the Model 5Õs top panel using the guide pins provided with the cover. See No. 38 on top panel illustration.
Day-to-Day Operation
To turn on the amplifier, move the Power switch from OFF or STBY to ON and wait for the front panel LED to turn green. At the end of a listening session, move the Power switch to STBY to extend the life of the tubes and maintain thermal stabilization. When you switch from STBY to ON, there is no thirty second waiting period. Standby is indicated by a red LED.
In the event that the power is disrupted due to a power failure or accidental power cord disconnec- tion, the Model 5 will default to the OFF power condition and go through a complete thirty second timing cycle before returning to ON. When the amplifier has been in the OFF position and is then moved to the ON position, the LED indicator will light in orange throughout the timing cycle and then light in green in the ON position. The orange LED will only appear from a power ON intialization for the duration of the timing cycle and at no other time.
Note: In order to avoid transient damage to your speakers, turn the volume control all the way down when you change program sources.
If you donÕt expect to use your audio system again within 24 hours, turn off the amplifier.
Always disconnect power from the Model 5 before removing tubes. Serious damage may occur to the Model 5 if any tubes are removed while the power is ON.
Do not overdrive the amplifier. Excessive input levels will drive the amplifier into distortion, reduce the life of the tubes and may damage the speakers.
