Audio Amplifier with Ultra Linear SIPP and SRPP Tubes

Figure 1 

The tube audio amplififer was designed using SRPP 12SL7 tubes as the driver stage and SIPP KT88 tubes as the output stage to produce a Class A Ultra Linear Amplifier.

This amplifier can be regarded as scalable since it can work with a number of octal vacuum tubes and can be built as a pair of push-pull Class A that contains ultra linear mono block tube amplifier. Each pair of mono block amplifier has its own power supply. It may be considered as more complex or costly but others would see it as cheaper, easier, and advantageous. The stereo version of this amplifier would require two power transformers, rectifiers, and filters. The tubes are operating on the principle of a heating element and bi-metal switch while the power supply is using a transformer with full wave bridge across the full winding.

In designing odd blocks of amplifier, the more sensitive circuitry is placed away from the power transformer to prevent noise interruption. Attached to the chassis will be the filter capacitors and the relay where the significant feature is the use of a ground buss using a large bare copper.

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