• Item: Three way horn system  
  • Type: DIY  
  • Posted: 22 May 2013  
  • Builder: Ray  
  • Country: United States  
  • Comments: 1  

R&Bs Horn system

The front loaded bass horns are made from walnut (horn surface) and cherry (frames that form the horn contour). The horn lens is 97” long with a 42” X 42” mouth.

The compression chamber is approximately 8 cubic feet.
Total horn length is 10 ½ FT. long.
I use an 18” driver with a 2:1 compression ratio at the throat.
In an open field they would go down to 34 HZ, but due to the placement in the room, I can hear slightly below 20 HZ. (No equipment to verify any of my frequency reproduction claims except a test CD and my ears) I roll them off at 150 HZ with an air core inductor (homemade) and a line level after-the-pre-amp filter.

The mid range, round front loaded horns are also homemade. I first made a mold with a plaster finish that was shaped with a Tractrix curve, made to accept 5” drivers. (1:1 compression ratio) I applied fiberglass cloth and auto body putty for mass and strength to form the outside of the horn lens.

The horn is approximately 26” long not counting the 5” long X 6” Dia. Compression chamber.
I covered the compression chamber with a hexagonal shaped walnut cover. It is supposed to play from 150 to 2000 Hz, but it seems to play at least up to 6000HZ without “falling off”.

The “tweeters” are simply round 6 ½” dia. ABS Lenses from MCM Electronics. I added some mass to the back side of the lenses (auto body putty) and also smoothed the factory Matte finish on the front side of the lens.

The tweeter compression drivers are from MCM Electronics. I covered the compression drivers with a hexagonal shaped walnut cover. The tweeters play from 2,000 to 20,000 Hz.

I play the mids and highs through a 100 W/Ch. Crown amplifier. The bass horns are played through a 105 W/Ch. Yamaha amplifier (initially given to me in non-working condition).

I made a line level filter/splitter that separates the mids and highs from the lows. (Signal path is stereo CD, Tuner, Turntable, etc into pre-amp. Stereo pre-amp output into filter. Stereo highs and mids from filter to the Crown amp. Stereo lows from filter to Yamaha amp.)


  • DorinD
  • 24 May 2013 at 09:18AM
  • That's my dream system!

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