The Great Plains Audio 604-8H-III is a much improved version of the vintage ferrite magnet Altec 604 family, and is currently in production. Compared to the early production ferrite Altec 604-16X discussed elsewhere in these pages, the GPA 604 exhibits very smooth and extended response. I was given the opportunity to measure these drivers some time ago, and came to the conclusion that a Butterworth 2nd order filter centered at 1500Hz with the crossover points spread 30% would both accomplish the necessary phase correction and also yield reasonably flat SPL magnitude throughout the crossover region. The drivers’ owner, and subsequent......
Great Plains Audio was born out of the Altec Lansing corporation in 1998. It carries forward the loudspeaker design and manufacturing tradition that began with Western Electric in the early 20th century. Great Plains Audio is the only place where the legendary Western Electric/Altec Lansing sound reproduction technologies live on.
7127 Northwest Third St. Oklahoma City,
Oklahoma, USA, 73127