Best RtoR tape for a Revox A77

The A77 can be set up for most tapes, including the ATRs that you mentioned. Setup includes setting the bias and EQ for the particular formulation so that you have a flat FR.

@cleeds is correct. Your Revox can work with any tape; it simply has to be calibrated to work with a particular tape in record mode.

Thank you!

Essentially, what you are saying is a flat FR is the ultimate goal when adjusting bias and EQ. If FR is flat, don't mess with anything? 

cwz

Just make sure that the azimuth is OK.

Essentially, what you are saying is a flat FR is the ultimate goal when adjusting bias and EQ. If FR is flat, don't mess with anything? 

If in playback, Yes.

If in record, also yes, but there are two approaches to setting record head bias that might be used on that machine. The first is the 'consumer method' which is to record at 100Hz and 10KHz, setting the bias so that during playback both tones playback at the same level. Then you adjust the record current (assuming the VU meters are properly calibrated) so that 0VU in record plays back at 0VU.

The 'pro audio' method is to record at 1KHz and increase the bias so that the playback peaks and then continue until the playback has fallen off by 1dB. This (or a similar technique, depending on the machine) should get you the lowest distortion rather than the flatest playback.