I'm Steve, My Riesong? Reisong?, I can never remember the spelling, A10 will be delivered tomorrow. I've already ordered some of the material for the modifications. This will be fun. I remember playing a 78-rpm copy of Rhapsody in Blue on my parent's Tube amp record player. The only other tube amp I ever fooled with was in the radio of my 1956 Buick. I had to pull that monster out of the dashboard and take the tubes to the drug store tube tester and buy 3 or 4 new tubes to get the radio to work. I guess everyone has figured out I'm pushing 75 years old. I have a decent sound system already, but I want to get the tube sound as an alternative. I'm rusty on vacuum tube theory but intend to learn as I go. My career has been in electrical controls and automation programming so I'm adept at soldering and reading schematic diagrams. However, I'm more familiar with silicon controlled rectifiers, TTL chips, AC and DC large motor drives, programmable controllers, etc. than with tube circuits. Can't wait to convert this A10 into a modified A12. I told my wife that this hobby is going to take the place of the sports car I almost bought. That should help justify the expenditures. Anyway, I'm glad to join this forum because if I try to talk about amplifiers, speakers, room acoustics, etc.with anyone in my extended family, all I see is their eyes glaze over. I need others to talk to so I can learn and discuss the things I'm interested in. I'll be posting in the question-and-answer category soon. And, I bought a Skunkie tee shirt to wear while I work on the amplifier mods.

Hello, I am interested in building a Single Ended amplifier with two 300B tubes connected in parallel. I did not find information about this subject in this forum or maybe I did not search well. If anyone has built an SE amplifier with 300B tubes in parallel, please share with us information about its schematic and construction. Thank you!

Hi I recently bulit the 300B and all works rather ok, the problem appeared some 2 weeks after occasionally use, the 300b valve died and then replacement too after some week of use, I have to admit when turning amp for the first time I didn't want to risk losing expensive valves so I bought the cheapest 300b available on ali-xpress "4300B", but when after turning the amp on it worked quiet well, no hum, sound without any distortion that I could hear (I don't have any measuring equipment so that must be as it is for the time untill I find a way to make a proper testing) I decided to leave the tubes for some time untill I'll be able to buy a better ones from some 'trusted' seller and this is when the tubes failed. I'm not sure the problem is in the tubes or the amp. The voltages are a bit higher than expected, the heater for 300B is perfect 4.99v, but the 6SN7 filaments are 6.8v the rest of voltage readings I put in the picture. I would appreciate any help, words of advise before turning the amp on for longer period of time with expensive(for me) valves ...the readings are with the new psvane I bought from uk store HiFiCollective. Thank you in advance