Bias level question.

[regebro]

I calibrated my Fostex A-8LR 8-track yesterday, and I did what Quantegy recommended for the 456 tape, and used a 3.0 db overbias at 10kHz. But this actually lowers the frequency response at 10kHz to about -2db, as compared with 1 kHz. Hummm...

My gut reaction here is to set the bias so that the frequency response is flat. What is your recommendation?

Ok, I see now that they recommend the bias setting should be done with an input level of -10db below reference, and I did it at reference level, so maybe that will change things, but if they don't? Should I instead set the bias so that I get a flat frequency response?