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6. ADVANCED FUNCTIONS
6.1. Power Selector, alternative output tubes
Position „HIGH“:
KT120
Position „LOW“:
KT88, 6550, KT90, KT100 (EL34 with Restrictions)
The Power Selector allows adjusting the RE 290 in accordance to the output tubes. Position HIGH
is reserved for the standard KT 120 tubes. In the HIGH Position the RE 290 is able to deliver 2 x
100 W RMS Output Power. The slightly weaker tubes type KT 88 or 6550 can be used in the
position LOW. In this position the maximum output power is limited to 2 x 70 W to avoid
overloading these tubes. The rather rare tubes of type KT 90 and KT 100 can be used also in the
LOW position.
The EL 34 can be used in the LOW Position in cases of speakers with an impedance higher than 4
ohms.
Tubes of Type 6L6, KT 66, 5881, EL 519 and EL 156 are not suitable for the RE 290.
Before switching the Power Selector turn OFF the mains push button switch
After switching from power LOW to HIGH and vice versa the BIAS should be corrected in case of
using the same output tubes. Normally there is only a slight correction necessary.
When using different tubes the BIAS has to adjust according to chapter 7.3
