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Reel to Reel Tape Machines / Re: Biasing for Studer A807 using RMGI 468 tape
« on: March 17, 2010, 01:31:14 AM »
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Hi Paul
In the late 60's I prepared tape heads for samples. I would do bias runs measuring output level and distortion and then frequency response. Hard polishing on an Arkansas stone would often "sharpen" up the gap. The customers were all down market such as Grundig and Fidelity and they were more interest in frequency response and rarely mentioned distortion. In fact automatic distortion meters had not been invented and they were manual with deep notches and many twiddly knobs! The temptation to quote a bias figure that was clearly a tad too low, was simply irresistible.
The company was Marriott Marnetics in Penryn Cornwall England, and "old man Marriott" built a shining new factory with a penthouse suite overlooking the river. He sold to IBM and then I moved away. But that was 40 years ago, the factory still exists but is a shadow of its former self.
Regards
Dave
Hi Paul
In the late 60's I prepared tape heads for samples. I would do bias runs measuring output level and distortion and then frequency response. Hard polishing on an Arkansas stone would often "sharpen" up the gap. The customers were all down market such as Grundig and Fidelity and they were more interest in frequency response and rarely mentioned distortion. In fact automatic distortion meters had not been invented and they were manual with deep notches and many twiddly knobs! The temptation to quote a bias figure that was clearly a tad too low, was simply irresistible.
The company was Marriott Marnetics in Penryn Cornwall England, and "old man Marriott" built a shining new factory with a penthouse suite overlooking the river. He sold to IBM and then I moved away. But that was 40 years ago, the factory still exists but is a shadow of its former self.
Regards
Dave