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Mondrian inspired open baffle + RCA 501S1

I won this 12" co-ax on eBay back in late '07 for a little over $100. There were only a few bidders and I was the only one based in the USA, the rest were in Japan. Had a feeling this might be a sleeper... 
When the package arrived I checked the condition of the capacitor with an LCR meter which turned out to be healthy. If it was leaky, I would have searched for a paper in oil cap that would fit in that very same clamp for authenticity and good sound.
I mounted it on this open baffle for testing and it turned out to be a very fine sounding speaker. It does not have the boogie factor of the Altec 605B duplex instead, it is refined and coherent like an Altec 755A. After a couple of weeks I carefully packed it up and waited for another unit to be listed....never saw another sample. ;o(

A special driver deserves a nice looking baffle

Staring at bare plywood for over 10 years can get boring even if the sound is good..;o) For a quite a while, I've had this idea lurking in the back of my mind of combining the aesthetics of my favorite period in art and architecture with DIY audio projects.
Piet Mondrian's Composition II in Red, Blue and Yellow, 1930 turned 90 degrees to the right ;)
After a few days wielding a brush, cans of paint and masking tape....


  1. she is very beautiful i would like to hear her sing again!

  2. Thanks jefjac! Ingat ka diyan, a great new year to your family and see you on your next visit!

  3. Hi! I stumbled into your blog here by accident today, a happy accident. The design on your open baffle stopped me dead in my tracks. YEAH !!! This makes me want to build the baffle first, then find some speakers. Thank you for being really good at being creative. Biggles

    1. Thanks for the kind words! Happy building, painting and listening.



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