EL504 ultra linear push pull power amplifier

This is a test setup I use for testing, designing and measuring tube (or valve) amplifiers.
This push pull amplifier is able to produce 45 watts of output power before clipping.
The tubes are somewhat matched for similar current flow in each one.
The amplifier uses a B+ of over 500 volts, with a grid bias of minus -113 volts. The input decoupled phase splitter drives two driver tubes to greatly increase the needed voltage swing to drive the power tubes.
It operates in ultra linear mode without global feedback.
Near the end of the video I turn up the amplifier to about 50% of power output, this loudspeaker is not able to handle more.
The loudspeaker used in this video is a Harbeth HL-P3 bookshelf monitor.
Music:
Moonlight by Smith The Mister smiththemister...

[@sw6188]

Looks fantastic, sounds good too! Can you tell me what output transformers you used here? Also do you have a schematic for your design? Thank you!

[@leukostad1592]

The output transformers used are the Hammond 1650H having a 6,6K primary. Recently I completed the build of this stereo power amplifier, it works really well but it needed careful adjustment and matching of tubes. If you do not have an oscilloscope and function generator chances are high you end up with an amp that is not working as intended.

[@sw6188]

@@leukostad1592 Thank you for the info. I have all the test gear I need for construction of this sort of equipment. Do you have a schematic for the amp?

[@leukostad1592]

@@sw6188 That's great. I just uploaded a video where I show the final build of this amplifier. The schematics are at the end of that video.

[@sw6188]

@@leukostad1592 Thanks! I'll check it out.

[@franktechnics]

Can you bring me schematic please?!

[@leukostad1592]

After this video I made another video about this amplifier where I show the build and schematic!