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Thursday, November 24, 2016

Single Ended 300B Mono Blocks


Just finished another set of 300B monos with 10Y driver.

A four chassis affair in my classic portrait style chassis:

Each mono block consists of the amp and a separate power supply.

Tango interstage and output transformers.

Of course with the ELROG ER300B as output tube.

Side views:

Yamamoto meter at the front to show the bias current of the output tube.

Best regards



  1. Very nice work! I'm really looking forward to listening with them. Thanks for the great pics.

  2. Hi, is there a specific reason to display the bias current ? I assume it is rather a retro design objective. Or is it an ON/OFF indication ?
    Congratulation to the new owner, have fun !

    1. It was requested by the customer who commissioned the amps and it gives an indication of the health of the output tube

    2. With those thoriated tubes you hardly need an ON/OFF indicator :-0