Last time I touched vacuum tubes was around 1967 when I was repairing radios and TV. I remember this old radio HIFI that was stripped from a console back in the early 60s There was a 12 inch speaker and a smaller speaker I think mid range and a small sealed back cone tweeter. There was a huge power transformer on the chases and a bunch of tubes. I do not remember what the output tubes were but I do remember them being in a push pull configuration. The sound was amazing and through out the years that followed I was never able to match the sound quality with all of the solid state amps I have built or heard. Recently with the hype on the vacuum tube single ended amp hoopla I started getting the bug and turned to the Internet for research.
The transistor brought a new theory in the amplifier and speaker industries. The current fad in solid state amps was to through a lot of current at a speaker in a small sealed cabinet. I will not debate with anyone about lots or little bit of power and how they sound.
As an attempt I wanted to build a tube power amp to see if I could find that good sound I heard when I was young. The following document contains the tube amp I chose as my first tube amp. Please note that I have never liked single ended power supplies for audio amps so it was not used.
While this document describes a plan to build an electronic device which has about 360 volts DC under the chases caution must be followed. I will not be held responsible for any injuries incurred from some one following this document.
MSH MODEL-1 POWERAMP (Michael S. Holden) make no representations about the suitability of this information for any purpose. It is provided "as is"
MSH MODEL-1 POWER AMP (Michael S. Holden) disclaims all warranties with regard to this information, including all implied warranties of merchantability and fitness, in no event shall MSH MODEL-1 POWERAMP (Michael S. Holden) be liable or any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortuous action, arising out of or in connection with the use or performance of this information.
This information may include technical inaccuracies or typographical errors.
MSH MODEL-1 POWERAMP (Michael S. Holden) may make improvements and/or changes in the information at any time.
Step 1: Circuit Design History
The origin of the power amplifier design came from the schematic below, which came from the 1959 RCA RECEIVING TUBE MANUAL Tech Series RC-19