Wow and flutter are audible time base distortions.
The study of analog tape playback could begin with the transport, the mechanism responsible for the time base accuracy of the recording. Time base distortions known as wow and flutter emanate from the transport, while higher frequency scrape flutter occurs inside the headblock.
Because tape recorders are designed to record tapes, they can't provide the best playback.
It might be startling to observe that the playback head of a professional tape recorder is in the wrong position for lowest scrape flutter. The reason the playback head is placed downstream of the erase and record heads is to permit monitoring "off tape" while the recording is taking place.
Achieving the highest fidelity playback requires a reproducer.
Scrape flutter is observable in laboratory measurements. It's also clearly audible in tape playback. Fortunately, we have reproducers, tape machines designed principally for providing optimal playback. There are no erase or record heads on a reproducer. A reproducer consists of only three main components: the transport (together with its associated control electronics), the headblock and the audio playback amplifier.
The transport's primary job is moving the tape at a constant linear velocity. This is not as easy as it might seem. Analog tape is extremely vulnerable to time base distortion (wow and flutter) introduced by the transport. Even the smallest perturbations in tape motion are audible. Transports can represent 80 to 90 percent of the manufacturing cost of the finest professional tape machines. It's unfortunate that many persons working professionally with analog tape lack an understanding of transport design fundamentals, such as forced-guidance versus precision-guidance, or servo constant tension.
Most people working with analog tape think first of the head re-lapping shops for advice or expertise on headblock modifications. But their popular practice of installing additional repro heads and switches into headblocks to make them "multi-format" capable is a poorly thought-out solution. Precision-guidance headblock design that eliminates scrape flutter while providing excellent dynamic azimuth stability is a specialized engineering discipline. We are proud that ATAE was the originator of SHRO (single-head-read-only) ultra-low-scrape-flutter headblock architecture.
The Playback Amplifier
The playback amplifier (also called the reproduce electronics) must be closely matched to the specific play head installed in the headblock. This interdependent system must then accurately align to the standard playback equalization curves. Each of our five different models of tape playback electronics delivers industry leading performance and sound quality, in large measure because they are the designs of recognized analog tape circuitry experts.
ATAE reproducers reflect a solid understanding of the physics underlying analog magnetic tape playback. Our Model One and Model Two ultra-low-flutter reproducers are built from famed Studer A820 and A80 precision-guidance, servo-constant-tension tape transports that are exactingly re-manufactured by us. Master tapes played back on our machines enable you to hear those tapes in the highest possible fidelity. ATAE products are sold under a comprehensive five-year warranty. Reproducer system pricing starts at $81,000. We are located in northern California.