2-Track Head Standard
The two-track head standard describes the track widths used by a stereo open-reel tape head.
The listed arrangements distinguish approximately 2 mm NAB tracks from approximately 2.75 mm DIN/IEC butterfly tracks. Track width is part of tape-format matching. It is separate from playback equalization, even where similar standard names appear in both specifications.
2-Track Head Standard — Reel-to-Reel
A two-track stereo tape divides its width between two audio tracks with a gap between them. The head standard describes the widths used to record or reproduce those tracks. Matching geometry matters when exchanging tapes; simply knowing that both machines are two-track is not the complete specification.
Compare the stated head standard or published track width for the fitted version. Do not infer it from the maker's country or an NAB/IEC equalization switch. A machine offered with alternative heads may need its configuration confirmed. Quarter-track and full-track arrangements are different formats and do not belong to this two-track classification.