I have a custom pair of open baffle GR Research (OB-5) (Just Tops) with assembled crossovers in a box for sale that use GR Research OB-5 MTM Top Sections mounted on a OB Truncated Pyramid Baffle 8" Top 10" Bottom, 24" high.
The MTM section (as in the GR Research OB-5/OB-7) consists of a pair of M-130/16's crossing in the 1,800Hz range to a BG Neo 3 pdr. The crossover point of the open baffle MTM section to the OB SW-12-16FR woofers is in the 200Hz range. The OB-5 sections have 91db sensitivity with 1 watt/1 meter and have about a 6 ohm average impedance load with a minimum impedance that drops to 4 ohms in the 4 to 5kHz range.
I purchased the drivers, crossover parts, and plans from GR Reseach. The Crossover components include Alpha Core foil inductors.combined with Erse poly caps and Sonicap Gen.2 by-pass caps and Sonicaps. Resistors are Mills and Lynk The crossovers are wired with JPS Labs wire from Danny approx. 35 feet. These were mounted on a w frame servo feedback bass section that I will be selling at a later date for $425 each.
OB-5 Tops.....$295/ Pair w/ crossovers from Danny. I also will include schematic.. I have pics I can send. Can ship!!! Parts cost over $650!
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