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Monday, March 14, 2016

300B Mono Blocks in Tower Style


The 300B monos in the tower style chassis are finished. These will go together with the 10Y line stage shown earlier this month. And will be used with power supplies in the same style.

These amps use the same circuit design and parts as the 300B monos built last summer. Just the chassis style is different. Signal section of one channel:

The interstage and output transformers are made by Tribute

The interstage transformer is placed on the top while the larger output transformer resides inside the chassis.

The tube sockets are on sub plates mounted below the top plate.

The two mono blocks with the matching line stage:

With tubes lit up:

Some more views:

View from the top:

More tube glow:

Best regards



  1. Hi Thomas,

    I like the minimalist approach, clean and uncluttered.. Those Tribute IT's are as large as most off-the-shelf SE OPT's for 300B's! The only thing I would change for myself (just dreaming) is I would like the 10Y facing the front rather than behind the Iron, especially on the preamp. But changing that might compromise layout efficiency...


  2. Hi Rick,
    the layout was chosen to minimise signal wiring inside

  3. I love it. I want one How many volts dose it take to come to full power.

    1. Hi! Do you mean the input sensitivity? It needs about 1V RMS from the preamp for full power out