Unsealed but unused
TDK SA-C90 Cassette — Professional High-Bias Blank Audio Tape
The TDK SA-C90 is a high-bias blank audio cassette tape engineered for versatile analog recording. Designed during the heyday of magnetic tape audio, this Type II (high-bias) cassette offers extended recording time and reliable performance for music enthusiasts, collectors, and analog recording aficionados.
Classic Analog Format
This cassette accepts audio input in a traditional analog format using magnetic tape housed inside a compact shell. Its C90 designation means up to 90 minutes of total recording time (typically 45 minutes per side), giving you room for full albums, mixtapes, long rehearsals, spoken word content, or archival recordings. Blank tapes like this were a standard medium before the rise of digital audio and remain popular among hobbyists who prefer the tactile feel and sound character of tape.
High-Bias Type II Tape
The SA-series from TDK uses a high-bias magnetic coating (often referred to as Super Avilyn) that improves frequency response and lowers noise compared with basic ferric oxide tapes. This formulation helps preserve clarity and dynamic range, making it well-suited for music recordings and detailed audio sources. High-bias tapes are intended to be used with Type II settings on compatible cassette decks to achieve optimal recording and playback results.
Build Quality and Reliability
The cassette shell is durable and engineered for smooth tape transport with minimal flutter and mechanical noise. TDK’s build quality has long been respected among analog tape users, and SA-series tapes were widely used by both casual recorders and serious hobbyists during the peak cassette era. While vintage production spans multiple years and factories, many of these tapes remain fully functional when properly stored.
Sound Character and Use Cases
Analog tape imparts a distinct warmth and saturation that many listeners find pleasing. The SA-C90 is especially useful for:
Creating personal mixtapes from vinyl, CD, or digital sources
Archiving analog audio from live performances, rehearsals, or field recordings
Testing and calibrating vintage cassette decks
Building a retro audio collection or hobbyist setup
Compatibility
This cassette is compatible with any cassette deck or recorder that supports Type II (high-bias) tapes. To achieve best results, use a deck with adjustable bias and equalization settings designed for Type II media.
Collector & Nostalgia Value
Beyond its functional use, the TDK SA-C90 appeals to collectors and fans of vintage audio equipment. Authentic tapes from earlier decades, especially Japanese-made units, are often sought after for their aesthetic appeal and build quality.
