The 5B-254/5M is a similar Retro Mono Block Version of the Brimar 25PI > 0.1 % distortion at full power , 25 watts Ultra Linear, 30 watts Tetrode including the new R Core Output Transformer 4Hz - 55KHz -1dB 4v@8K, or Lundahl Transformers ,very similar footprint to the Quad 11 Mono's .
The 5B-255M also has a triode mode switch and similar to the Vintage UK Parmeco A.P. 32020 in its design.
The 7591A is well known in the Vintage Macintosh 225 and Fisher Amplifier range Fisher X-101c , we will reflect the Vintage look and design in our Push Pull 7591A -Mono Blocks, 26 watts
More to come on this !
World renown manufacturer