Class A EL84 6BQ5 Push Pull Tube Amp
Bruce Heran of OddWatt Audio has shared another of his great sounding OddWatt
amplifier designs with the DIY community. His latest amplifier project shares a similar topology with the other OddWatt tube amplifier projects available on the DIY Audio Projects website. His latest project is similar to the first Push-Pull EL84 (6BQ5) Oddwatt project posted two years ago. Both of the
tube amp projects use EL84 (6BQ5)
vacuum tubes in the output stage. The first OddWatt amplifier used a ECC802S SRPP
driver stage while this one uses a 5751 SRPP driver stage. The main difference between the two amps is that this one uses smaller Edcor audio output
transformers making it easier and less costly to build. A photo of the finished amplifier project is shown below (click on the photo for an enlargement).
There are a number of improvements to the circuit. With the 5751 driver stage the higher gain of the new tube amp will allow for direct connection of portable MP3 players. The amplifier will produce about 5 to 7 watts of high quality sound with good performance between about 25 Hz to beyond 20kHz. The new amplifier measures very well and Bruce reports that the amp sounds very good with clean, detailed mids and highs and a great sound stage. Complete details for this project are available from the 5751 SRPP / EL84 (6BQ5) Push-Pull DIY Tube Amplifier project page.
Wish you had entered a diagram. I want to build a stereo amplifier using the 6BQ5's. The output transformers that I have are designed to be used with these tubes, and the transformer only has a B+ lead, and two plate leads in the primary. Everything that I have found, has five leads, two feeding G2 of the 6BQ5. I know there has to be a diagram out there somewhere, for the transformers came out of a Bladwin amplifier used in conjunction with an organ, but can't find that diagram either. Guess it's just bad luck.... Jim
ReplyDelete