Thanks to Bob and guys like him who are willing to challenge some of our commonly held misconceptions with real data. The Fostex FE-166E Voigt pipes I built (and sold to Jim) were loosely based on the Lowther Club of Norway design. To my ears they are pleasant sounding, especially when placed in a room whose dimensions accentuate the 60-80hz range, but they definitely are colored. Having heard Bob's FT-1600 MKII design in one room at the GPAF, with the Voigt pipes only two doors down, I have to agree that Voigt pipes aren't the best enclosure design for Fostex drivers.